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The present invention relates to a sanitization system combined with a neck brush wherein the brush contains skin powder customarily brushed on a salon patron.
BACKGROUND OF THE INVENTION
Neck brushes have been used to clean cut hair from a salon patron's neck for centuries. These simple brushes are sometimes dipped into skin powder which soothes the patron's neck. More recently, brushes were developed to hold the powder and dispense the powder.
U.S. Pat. No. 2,966,176 to Bradley discloses improvements in a brush holder and powder applicator for a barber's duster brush. Powder container D is squeezed and powder is delivered to brush bristles. A “germicidal lamp H” sanitizes the powder. U.S. Pat. No. 1,757,650 to Arico discloses a brush with a powder containing chamber at one end. The brush has an independent brush head to be used upon each customer when it is desired to remove the cut hairs from the face, head or neck, under such conditions providing for sanitation. U.S. Pat. No. 2,657,410 to Stroup discloses a neck duster especially useful in barber and beautician shops. The neck duster has a disposable container for antiseptic powder and the container has a perforated top to permit passage of the powder to the bristles of a brush head. The container and the brush head are detachably secured together by means of a handle. U.S. Patent Application Publication No. 2006/0175554 to Riddell discloses a germicidal brush cleaner that uses a germicidal UV light (para. 024) to disinfect the individual bristles on a plurality of toothbrushes and a hairbrush. Each toothbrush and hairbrush includes bristles made of optical fibers capable of transmitting ultraviolet light. There is also a special method of attachment of the toothbrush inside the cleaner that secures the toothbrushes in a set position in the holder. The germicidal light source may be a germicidal fluorescent ultraviolet lamp. The light rays from the germicidal light source are directed at the opposite ends of the bristle at the critical angle, or slightly greater than the critical angle, in order to attain total internal reflection of the light down the bristles of the toothbrushes.
The other references showing neck brushes are: U.S. Pat. No. 2,592,020 to Farone discloses disposable sanitary-type neck dusters. U.S. Pat. No. 1,714,508 to Keele discloses a sanitary brush. U.S. Pat. No. 2,825,080 to Bongiovanni discloses a combination neck brush and powder dispenser for use by a barber. U.S. Pat. No. 2,129,777 to McGrath discloses a system, used in connection with barbers' duster brushes, wherein the bristles of the brush may be sterilized each time the brush is used. U.S. Pat. No. 2,582,992 to Hergert discloses a brush or duster for use in barber shops.
However, current health code regulations require that most, if not all, barbershop and salon utensils, which touch a patron's hair or neck, be sterilized before and between each use. The utensil should be sterile for each use. Therefore, many of the prior art neck brushes, with and without powder dispensers, do not have a sanitization system. Further, many health code regulations require that the government inspector visually see, during a quick inspection of the salon, that the sanitization process is being properly applied to all beauty salon and barbershop utensils.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a sanitization system and a neck brush wherein the brush contains skin powder to be used on a salon patron.
It is an additional object of the present invention to have a sanitization system wherein ultraviolet light (“UV”) is directed to the brush bristles and any retained skin powder held by the brush bristles.
It is another object of the present invention to provide a system wherein the sanitization process by the ultraviolet UV lamp can be confirmed without opening the canister.
It is a further object of the present invention to provide a canister which holds the sanitized brush and brush skin powder.
SUMMARY OF THE INVENTION
The sanitized brush, with skin powder, is retained in a sanitization system. The neck brush has a brush handle, a bristle face and a plurality of bristles extending outward from said bristle face. The brush handle is a two-piece element (in the preferred embodiment) and the handle defines an interior chamber which holds skin powder therein. The powder is adapted to be applied to a neck of a salon patron by an operator who brushes cut hair form the neck of the patron during a hair styling operation. The brush handle has a powder loading port therein to permit access to the interior chamber such that said skin powder can be delivered into said chamber. A portion of the chamber wall of the interior chamber is flexible. A movable actuator disposed in the handle has an operator surface and an actuator end on the flexible chamber wall. When the actuator is depressed by the operator, the wall moves inward which compresses the size of the chamber. The bristle brush face defines a powder exit port and this port adjoins an exit passage extending from the bristle face to the chamber such that upon actuation of the operator surface and resultant movement of the flexible chamber wall, the chamber compresses resulting in the ejection of skin powder from the chamber through the exit passage and the exit port into the plurality of bristles extending outward from the bristle face. The sanitization system also includes a brush stand to support the neck brush about the brush handle and a sensor system to determine when the neck brush is disposed on the brush stand. The sensory system is an on-the-hook mechanical or optical system (when the brush is on the stand hook arm). An ultraviolet UV sanitizing lamp is directed at the plurality of bristles and any retained powder captured therein. A timer, electrically coupled between a power source and the lamp, is triggered ON by the sensor system and supplies power to the lamp for a predetermined period of time, and thereafter disconnects the power from the lamp when the timer counts down and turns OFF.
Additional features of the sanitizing neck brush system include: (a) a base supporting the brush stand (the stand extending upwards from the base), wherein the stand retains brush bristles vertically above the UV lamp; (b) a battery and a recharger unit; (c) the sensor system configured as a mechanical switch on or in or connected to a movable stand, or an optical sensor controlled switch; and (d) a cover removably mounted atop the base to cover the brush on the stand wherein the cover has a transparent wall segment to visually confirm a lamp ON condition.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the present invention can be found in the detailed description of the preferred embodiments which follow when reviewed in conjunction with the accompanying drawings in which:
FIG. 1 diagrammatically illustrates the sanitization system and neck brush which contains skin powder therein;
FIG. 2 diagrammatically illustrates a simple electronics diagram for the system;
FIGS. 3A and 3B diagrammatically illustrate sensor systems to determine when the brush is resting on the brush stand in the sanitization case.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention relates to a sanitization system for a neck brush wherein the brush contains skin powder to be used on the neck of a salon patron. Similar numerals designate similar items throughout the drawings.
FIG. 1 diagrammatically illustrates sanitization system 10 which generally encases and retains neck brush 20 . Brush 20 contains skin powder 70 . The sanitization system or unit 10 , in the preferred embodiment, includes a removable upper cover 12 and a base 14 . Cover 12 may be entirely transparent but if not entirely clear, at least an area designated as window 16 should be transparent. Window 16 (or the entire cover if the entire cover is transparent) must be somewhat near light emitting port 9 on top, flat surface 7 of base 14 . Light emitting port 9 emits ultraviolet or UV light 11 shown by arrows 11 emitting from light port 9 . Therefore, the UV light 11 is generally visible through transparent window 16 (or the entire cover 12 if the cover is clear or transparent). Cover 12 has an edge fitting or complementary notch or step 15 which matches notch or step 17 in base 14 . In this manner, when cover 12 is placed on base 14 , a relatively sanitized area is established in the inside of the cover and atop the base as a sanitization system. As an additional feature, notch 15 , 17 may include an O ring to enhance the sanitization and sanitary nature of the interior space of the entire system.
Inside base 14 is a UV light or lamp diagrammatically shown as UV light system 19 , and a power conversion and control system 6 . A manual ON/OFF switch 3 can be utilized to turn ON and OFF UV lamp 19 as shown by double headed arrow 2 . The electrical power control system 6 for UV lamp 19 is supplied line power generally by an AC cord 1 leading to an AC power source. As explained later, electrical system 6 may include a battery which is rechargeable by the AC power source.
In the illustrated embodiment, brush 20 is a two part brush wherein the top brush handle 22 is threadably attached via threads or other snap-on or other locking mechanism 24 to lower brush body 26 . In the illustrated embodiment, a chamber 28 is defined by the lower brush body 26 . In a different embodiment, chamber 28 is located in upper handle body 22 and only exit passage 30 extends through lower handle body 26 . As shown in FIG. 1 , chamber 28 has at its bottom segment, a frustoconical narrowing segment 32 leading to exit passage 30 . An exit port 34 is defined on brush bristle face 36 . A plurality of bristles 40 extend outwardly from bristle face 36 . When on the stand bristle face 36 is parallel to UV lamp lens 9 to assure UV light distribution over all the bristles.
In the illustrated embodiment, the upper handle body 22 has a flexible chamber wall 50 . Chamber wall 50 moves inward toward chamber region 28 as shown by double headed arrow 52 . The flexible chamber wall 50 compresses chamber 28 based upon movement of actuator 60 . Actuator 60 is movably disposed in upper handle segment 22 . The actuator moves up and down. Actuator 60 has an operator interface 62 and moves up and down as shown by double headed arrow 64 . When the operator depresses surface 62 , actuator 60 is depressed thereby moving flexible wall 50 to a position shown by dashed line 51 . When the flexible wall 50 is moved downward by actuator 60 , the volume or space in chamber 28 is compressed or reduced thereby forcing skin powder 70 retained within chamber 28 to be ejected or forced through exit passage 30 and out exit port 34 and into the plurality of bristles 40 . Flexible wall 50 is biased to force actuator 60 upward after the depression operation. If the chamber compression and release is too forceful, powder may not be adequately ejected. A one-way valve, which permits air to be drawn into chamber 28 during the upward return of actuator 60 , may be incorporated into brush 20 . The valve relieves the “return vacuum” caused by retraction.
When the UV light 11 is turned ON by the electrical system 6 , UV rays illuminate the plurality of bristles 40 and any retained skin powder held by the bristles. Powder 70 in chamber 28 is maintained in a sterile condition since the powder is sterile when it is placed in the container. The powder is placed in container or chamber 28 by the user threadably removing upper handle 22 from lower handle 26 via threads 24 . A snap or an O ring lock may be use rather than threads 24 . In any event, the user places sterile powder in chamber 28 and then seals the upper handle unit 22 to the lower unit handle 26 . Therefore, the powder in chamber 28 is maintained in sterile condition and the sterile condition is maintained until the powder is ejected into bristles 40 . During use, the salon operator, barber or beautician opens cover 10 by vertically moving the cover upwards from base 14 thereby exposing brush 20 and bristles 40 . The operator then removes the brush from brush stand 80 and brushes the salon patron's neck depositing powder on the skin of the patron. The user then replaces brush 20 on a brush stand 80 . The brush stand 80 is attached to the base 14 as discussed later in connection with FIG. 3A . As discussed later, when brush 20 is placed on stand 80 , lamp 19 is activated and UV rays 11 illuminate bristles 40 and any retained powder in the bristles thereby sanitizing the brush 20 , bristles 40 any retained powder in bristle 40 and generally the entire inside of the container. It is preferred that the operator replace cover 10 onto base 14 thereby permitting UV light 11 to sterilize the entire interior of the container.
When health officials or other governmental agency members visit the salon or barber shop, those officials can easily see that the UV lamp is turned ON thereby sterilizing the entire neck brush and any exposed powder.
FIG. 2 diagrammatically illustrates one basic electrical system for powering UV lamp 19 . AC power is supplied on line 1 a to a charger unit 90 . Charger unit 90 converts the AC power to DC power and applies the same to line 1 b . A coupling 92 permits the user to plug and unplug charger 90 from base 14 and electrical system 6 . The coupler may be on a surface of base 14 . Electrical unit 6 includes, in a preferred embodiment, a rechargeable battery 94 and a switch 96 activating timer 98 which supplies power to UV lamp 19 . Of course, the electrical system may be more complex since timer 98 could be a digital timer that turns ON and OFF a power switch (not shown) directly coupling battering 94 to UV lamp 19 . Further, the power supply to UV lamp 19 may need conditioning to increase or decrease voltage or applied to the current. Persons of ordinary skills in the art would know how to provide such conditioned power to lamp 19 as well as how to turn ON or OFF lamp 19 based upon the output of timer 98 . Switch 96 is controlled either manually by ON/OFF switch 3 (a slide switch shown in FIG. 1 ) or other types of manual switches (other than a slide switch). More importantly, switch 96 is controlled by a brush support sensor 97 that will be discussed later in connection with FIGS. 3A and 3B . If manual switch 3 is in the OFF position, when brush support sensor 97 is activated by the brush mounted on stand 80 , switch 96 is closed thereby feeding power from battery 94 through the timer 98 to UV lamp 19 . Timer 98 is utilized to keep the lamp 19 ON for a certain period of time (a predetermined period of time) and then automatically turned OFF. This time may be set by a health code regulation or may be subject to a manual override or some type of multiple time on period adjustment. In other words, adjuster 99 may be a multi-position switch turning ON the timer for 1 hour, 2 hours, or 3 hours (a three position switch). The manual override could be used to turn OFF the timer such that as long as the brush is on handle 80 ( FIG. 1 and FIGS. 3A and 3B ), the UV lamp is ON (an always ON automatic control). In this different control system, the salon operator would turn ON or OFF the UV lamp by manual switch 3 . In this manner, the system can be adjusted depending upon the health code regulations for particular salons. Some health codes would require the UV lamp to be ON during all normal business hours (manual switch ON, timer disconnected or “always on”) whereas other health codes may require the UV lamp to be ON only for a certain predetermined periods of time such as 1 hour, 2 hours etc. The present system provides a sanitization unit for multiple jurisdictions having different health regulations.
In addition, the AC power source in charger 90 may be eliminated. In other words, the system may be powered simply by a battery 94 that is periodically replaced by the salon operator. An electrical unit to convert the AC power will be required. Since the cover 12 has a view port 16 , the salon operator can easily determine when the UV lamp is permanently OFF indicating that battery 94 has been fully depleted of power and needs replacement.
FIG. 3A shows that brush stand 80 has a horseshoe or U-shaped configuration which partly wraps around the lower region of brush segment 26 . Returning to FIG. 1 , brush region 26 has a lower lip 27 that is complementary to brush stand arm 80 . Returning to FIG. 3A , brush stand 80 moves vertically up and down on base 14 as shown by double headed arrow 81 . In the lower position 80 a , stand 80 and particularly stand post 83 activates switch 96 thereby turning ON the timer 98 and ultimately UV lamp 19 . The post is biased upward such that when the brush is not on the stand, the post moves slightly upward turning OFF the UV lamp. If the brush is removed while timer 98 is still in the countdown ON timing session, the power to the UV lamp remains ON. Returning the brush to stand 80 may reset timer 98 such that the timer 98 keeps UV lamp 19 ON for a predetermined time. The predetermined time is set to be equal and to exceed the time required by the health code regulations.
FIG. 3B shows that brush stand 80 has a sensor 110 proximate the brush 20 . Sensor 110 could be a mechanical switch that is directly activated and actuated by brush handle segment 26 (when the brush is on the stand) or sensor 110 may be an optical sensor which detects the difference in light when the brush 20 is on stand 80 as compared as when the brush is off the stand 80 . The output from sensor 110 is fed to switch 96 .
The claims appended hereto are meant to cover modifications and changes within the scope and spirit of the present invention | The sanitized brush, with skin powder, is retained in a sanitization system. The neck brush handle has a powder chamber, a bristle face with outwardly extending bristles and a powder input port. A portion of the powder chamber wall is flexible and a movable actuator depresses the flex-wall, compresses the size of the chamber and forces powder from an exit port on the bristle face. The sanitization system includes a brush stand holding the brush above a UV lamp. A sensor determines when the brush is on the stand and a timer is triggered ON controlling the lamp and counts down OFF. Additional features include: a base supporting the stand above the UV lamp; a rechargeable battery; an on-hook brush sensor (mechanical or optical); and a removable cover with a transparent segment to visually confirm lamp ON condition. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of and claims priority from U.S. application Ser. No. 14/788,169, entitled PROVIDING INFORMATION TO A MOBILE DEVICE BASED ON AN EVENT AT A GEOGRAPHICAL LOCATION, filed Jun. 30, 2015, issued U.S. Pat. No. 9,215,564, issued Dec. 15, 2015, which is a continuation of U.S. application Ser. No. 14/586,294, entitled PROVIDING INFORMATION TO A MOBILE DEVICE BASED ON AN EVENT AT A GEOGRAPHICAL LOCATION, filed Dec. 30, 2014, issued U.S. Pat. No. 9,094,794, issued Jul. 28, 2015, which is a continuation of U.S. application Ser. No. 14/178,712, entitled PROVIDING INFORMATION TO A MOBILE DEVICE BASED ON AN EVENT AT A GEOGRAPHICAL LOCATION, filed Feb. 12, 2014, issued U.S. Pat. No. 8,923,890, issued Dec. 30, 2014, which is a continuation of U.S. application Ser. No. 13/793,909, entitled PROVIDING INFORMATION TO A MOBILE DEVICE BASED ON AN EVENT AT A GEOGRAPHICAL LOCATION, filed Mar. 11, 2013, issued U.S. Pat. No. 8,655,386, issued Feb. 18, 2014, which is a continuation of U.S. application Ser. No. 13/537,565, entitled PROVIDING INFORMATION TO A MOBILE DEVICE BASED ON AN EVENT AT A GEOGRAPHICAL LOCATION, filed Jun. 29, 2012, issued U.S. Pat. No. 8,412,238, issued Apr. 2, 2013, which is a continuation of and claims priority from U.S. application Ser. No. 12/150,413, entitled PROVIDING INFORMATION TO A MOBILE DEVICE BASED ON AN EVENT AT A GEOGRAPHICAL LOCATION, filed Apr. 28, 2008, issued U.S. Pat. No. 8,219,110, issued Jul. 10, 2012, the entire contents of which are incorporated by reference herein.
FIELD OF THE INVENTION
The present disclosure is generally related to a communications network, and more particularly to providing information to a mobile device based on an event at a geographical location in a communications network.
BACKGROUND OF THE INVENTION
When an event occurs in a specific location, government agencies that respond to or are responsible for the event may send out alerts to nearby entities with details about the event. In this way, others may take preventative actions against the event. For example, an accident may have occurred at a busy interchange of highways. Current transportation authorities who monitor traffic flows may send out text alerts to electronic signals positioned at various highways to alert drivers nearby. Drivers who saw the text alert may then take preventative actions against the event, for example, by taking an alternate route.
While current systems adequately alert events to people nearby, they fail to provide alerts to those who are on the move, for example, those who are not in the nearby area but are approaching the event location. This failure is due to the limitation of current systems, which provide alert information only to fixed locations, such as pre-installed electronic signals or wired telephone lines. Therefore, what is needed is ability to provide information to those who are not fixed in position, for example, mobile device users, no matter where they or their devices are geographically located.
SUMMARY OF THE INVENTION
The present disclosure describes a method for providing information to a mobile device based on an event at a geographical location. An occurrence of an event is detected. A determination is made as to whether the event is a specific event and if the event occurred at or near a geographical location. If the event is the specific event, occurs at or near the geographical location, and if the at least one mobile device is located at or near the geographical location, an alert of the event is sent to at least one mobile device.
In one embodiment, the detection of the event comprises sensing by a sensor an occurrence of an event above a predetermined threshold. Alternatively, the detection comprises capturing information about the event by at least one mobile device, sending the information to at least one service provider site, and forwarding the information to a repository.
In order to send an alert to the at least of mobile device, information about the event is first processed. An image is recognized from the information about the event, a type of the event is identified based on the image, and a location of the event is identified based on a location of the at least one mobile device.
When sending an alert of the event to at least one mobile device, in one embodiment of the present disclosure, a lookup of at least one mobile device associated with at least one service provider site is performed. The alert is then sent to the at least one mobile device associated with the at least one service provider site. In an alternative embodiment, the alert is sent to at least one service provider site. The alert is then forwarded from the at least one service provider site to at least one mobile device associated with the at least one service provider site.
In yet another embodiment of the present disclosure, a lookup of at least one mobile device associated with at least one service provider site is performed. A location of the at least one mobile device is identified. The alert is then sent to the at least one mobile device within a predetermined distance of the event based on the location.
In still yet another embodiment of the present disclosure, a location of at least one service provider site is identified from a geographical information system. The alert is sent to the at least one service provider site within a predetermined distance of the event based on the location. The alert is then forwarded from the at least one service provider site to at least one mobile device associated with the at least one service provider site.
In addition to sending alert messages based on geographical locations, the alert may be sent to the at least one mobile device based on a period of time the at least one mobile device is registered with a service provider site.
In a further embodiment of the present disclosure, a communications network for providing information to a mobile device based on an event at a geographical location is provided. The communications network comprises at least one mobile device utilized by at least one mobile user, at least one service provider site associated with the at least one mobile device; and an event alert system operable to detect an occurrence of the event, process information related to the event, and send an alert of the event to the at least one mobile device if the event is a specific event, if the event occurs at or near a geographical location, and if the at least one mobile device is located at or near the geographical location.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts one illustrative embodiment of a communications network for providing information to mobile device based on an event at a geographical location.
FIG. 2 depicts an alternative embodiment of a communications network for providing information to mobile device based on an event at a geographical location.
FIG. 3 depicts a flowchart of a method for providing information to mobile device based on an event at a geographical location.
FIG. 4 depicts a flowchart of one exemplary method for sending alert messages directly to mobile devices.
FIG. 5 depicts a flowchart of one exemplary method for indirectly sending alert messages to mobile devices.
FIG. 6 depicts a flowchart of an exemplary method for detecting the event from a mobile device.
FIG. 7 depicts a flowchart of one exemplary method for processing the information in a repository or database.
FIG. 8 depicts a flowchart of an exemplary method for providing information to a mobile device which initiated event monitoring.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1 , one illustrative embodiment of a communications network for providing information to mobile device based on an event at a geographical location is depicted. In communications network 100 , event monitor 102 is responsible for monitoring events 104 that occur in various geographical locations. Examples of event monitors include government or municipal agencies, such as police, fire departments, public safety answering points, and the like. Examples of events being monitored include a traffic accident, a construction detour, an explosion, a fire, a police pursuit, and the like.
Event monitor 102 may recognize events 104 by using operators or sensors 106 that are installed at the various geographical locations for detecting the occurrence of events 104 . Examples of events that sensors 106 may detect include earthquakes, rain storms, electricity outage, and the like. In addition to sensors 106 that are installed at various geographical locations, sensors 106 may be installed within the event monitor 102 for monitoring events that occur above a predetermined threshold. For example, sensors 106 may be installed at the event monitor 102 to detect vibrations above a predetermined threshold to alert an earthquake.
When the event monitor 102 detects or senses an event 104 , the event monitor 102 notifies an event alert system 108 . The event alert system 108 stores the event 104 in a repository or database 110 and determines if the event is a specific event and if the event occurs at or near a geographical location. The event alert system 108 determines whether the event is a specific event based on a type and/or location of the event.
If the event is a specific event and if the event occurs at or near a geographical location, the event alert system 108 provides information related to the event to mobile devices 114 at or near the geographical location. In one illustrative embodiment, the event alert system 108 alerts the mobile device 114 by directly sending alert messages to mobile device 114 . In order to send alert messages directly to mobile device 114 , the repository or database 110 may comprise information of mobile device 114 at or near the geographical location. For example, repository or database 110 may comprise a table of mobile identification numbers (MINs) associated with service provider sites 116 at or near the geographical location. A mobile identification number (MIN) uniquely identifies a mobile device in a service provider network.
While alerts may be sent to mobile device 114 at or near the geographical location, the event alert system 108 may sent alerts to mobile devices 114 that are within a certain distance of the event 104 . To determine the location of mobile device within a geographical area, the event alert system 108 may consult data stored within the geographical information system (GIS) or global positioning system (GPS) 118 . For example, alerts may be sent to mobile device that are within a certain number of feet, miles, or yards of the event. In this way, only mobile devices 114 that are located within a certain distance of a geographical area affected by the event 104 may be alerted. No disruptions will be caused to the other devices.
In an alternative embodiment, the event alert system 108 may alert the mobile device 114 by sending alert messages to service provider sites 116 or other systems at the geographical location or within a certain distance of the event 104 . Since each service provider site 116 keeps track of its mobile device 114 with their mobile identification numbers (MINs), no mobile device information will be stored in the repository or database 110 . However, to determine service provider sites located at a geographical location or within a certain distance of the event, the event alert system 108 may consult data stored within the geographical information system (GIS) or global positioning system (GPS) 118 . In response to receiving alert messages from the event alert system 108 , service provider sites 116 forward the alert messages to its mobile devices 114 , which in turn notify their mobile users 112 .
The event alert system 108 may instruct service provider sites 116 to send a specific message to a mobile device 114 based on its location and heading relative to the event. For example, service provider sites 116 may send alert message A to mobile device 114 that are moving towards the event 104 . Service provider sites 116 may also send alert message B or no alert message at all to mobile device 114 that are moving away from the event 104 . In order to detect mobile device's location and heading relative to the event, the event alert system 108 may consult data stored within GIS/GPS system 118 . In addition, service provider sites 116 may detect the received signal strength indication (RSSI) of its mobile devices 114 and determine their locations and headings relative to the event. Alternative to a specific message, the event alert system 108 may also instruct service provider sites 116 to send a generic alert message to all associated mobile device 114 with information related to the event 104 .
Alternative to detecting events by event monitor 102 , events may be detected by the event alert system 108 from a reporting of the event originated from a person involved in the event or bystanders. FIG. 2 provides an alternative embodiment of a communications network for providing information to mobile device based on an event at a geographical location. In communications network 200 , a person involved may capture information of the event 204 with mobile device 214 . For example, mobile user 212 may take a picture of a scene of the accident with mobile device 214 . Other examples of information captured by the mobile user 212 include videos, graphics, sounds, and the like.
Mobile user 212 may then report the event by sending the event information from mobile device 214 to the event alert system 208 via service provider sites 216 . In response to receiving the event information, the event alert system 208 stores the event information in repository or database 210 . Based on the event information, the event alert system 208 may utilize the GIS/GPS system 218 and image recognition software 220 to identify the location and/or the type of the event 204 . The location, the type or a combination of the location and type of the event identifies the event as a specific event. The event alert system 208 then sends alert messages directly to mobile devices 214 at the geographical location or within a certain distance of the event 204 . Alternatively, the event alert system 208 may send alert messages to service provider sites 216 at or near the geographical location or within a certain distance of the event 204 . In response to receiving alert messages from the event alert system 108 , service provider sites 216 may forward the alert messages to associated mobile devices 214 , which in turn notify their mobile users 212 .
FIG. 3 provides a flowchart of a method for providing information to mobile device based on an event at a geographical location. Process 300 begins at step 302 with detecting occurrence of an event. In one embodiment, the event may be detected using sensors. Alternatively, a person involved or bystanders may report an event by capturing event information with mobile devices. Next, the process continues to step 304 to determine if the event is a specific event, if the event occurs at or near a geographical location. The process then completes at step 306 to send alert messages either directly or indirectly to mobile devices if the event is a specific event, if the event occurs at or near a geographical location, and if the mobile device is at or near the geographical location.
FIG. 4 provides a flowchart of one exemplary method for sending alert messages directly to mobile devices. The process 306 begins at step 402 with performing a lookup of mobile devices associated with service provider sites based on their mobile identification numbers (MINs). In this example, the lookup may be performed at the service provider sites. Next, the process continues step 404 to determine whether alert messages should be sent to all mobile device at a geographical location or within a certain distance of the event.
If alert messages are to be sent to mobile devices at a geographical location, the process continues to step 406 to send alert messages to MINs associated with service provider sites at the geographical location. However, if alert messages are to be sent to mobile devices within a certain distance of the event, the process continues to step 408 to consult locations of mobile devices from data stored within a GIS/GPS server and completes at step 410 to send alert messages to MINs within a certain distance of the event.
FIG. 5 provides a flowchart of one exemplary method for indirectly sending alert messages to mobile devices. Process 306 begins with step 502 with determining whether alert messages should be sent to all mobile devices at a geographical location or within a certain distance of the event. If alert messages are to be sent to all mobile devices at a geographical location, the process continues to step 504 to send alert messages to service provider sites that are located at the geographical location. Subsequently, the process continues to step 506 to forward alert messages to MINs associated with the service provider sites.
However, if alert messages are to be sent to all mobile devices within a certain distance of the event, the process continues to step 508 to consult locations of service provider sites from data stored within a GIS/GPS server and to step 510 to forward alert messages to service provider sites that are within a certain distance of the event. The process 306 then completes at step 506 to forward alert messages to MINs associated with the service provider sites located within a certain distance of the event.
As discussed above, instead of using sensors to detect occurrence of events, a person involved or bystanders may report event information using their mobile devices. FIG. 6 provides a flowchart of an exemplary method for detecting the event from a mobile device. The process 302 begins at step 602 with a mobile user capturing information of the event with a mobile device. Next, the process 302 continues to step 604 to send the captured event information from a mobile device to a service provider site. The process 302 then completes at step 606 to forward the captured event information from the service provider site to the event alert system. Once the captured event information is received, the event alert system may store and process the information in a repository or database.
FIG. 7 provides a flowchart of one exemplary method for processing the information related to the event in a repository or database. The process 304 begins at step 702 with recognizing an image from the captured event information. To accomplish this step, the captured event information may be compared to images stored within an image recognition software system. For example, the scene of an accident may be recognized by the image recognition software by comparing it to images of intersections stored within the image recognition software system.
Next, the process 304 continues to step 704 to identify a type of the event based on the recognized image. To accomplish this step, the information from the captured image may be compared to information stored within the repository or database. For example, the accident scene image recognized by the software may be compared to information stored within the repository or database and an accident event is identified. After the type of event is identified, the process 304 continues to step 706 to identify location of the event based on the location of the mobile device reporting the event or a recognized image. To accomplish this step, the event alert system may consult data stored within a GIS/GPS server. Based on the type, the location, or a combination of the type and location of the event, alert messages may be sent to mobile devices that are at or near the geographical location.
In addition to alerting events to mobile devices based on geographical location, alert messages may be sent based on time periods spent by mobile users in a particular geographical location. For example, alert messages may be sent only to mobile devices that have passed through or are registered with a service provider site within a certain period of time. Examples of periods of time include months, weeks, days, hours, minutes, and the like. In this way, alerts may be sent to mobile devices that are within the reach of a service provider site for a specific period of time. For example, if an accident occurred in a particular geographical location half an hour ago, alert messages may be sent to mobile device that have passed through or are registered with a service provider site located within a certain distance of the event for the past half hour, such that mobile users in the vicinity of the accident may take preventative action to avoid the scene. In order to identify mobile devices based on a period of time, it is preferable to store mobile identification numbers (MINs) associated with each service provider site for a period of time in the service provider site, a repository, or a database.
It is noted that the alert messages being sent to the mobile devices may include information related to the event in a form of text, voice, sound, graphics, email, short messages, and the like. In the event that a short message alert is sent, the message may be sent via a short message servicing center. In addition to text alerts, alert messages may include additional information about the event. For example, the alert message may include a link to obtain further information related to the event, a link to a map surrounding the location of the event, a suggestion of alternate route, etc. Furthermore, additional information about the event may include instructions from government agencies indicating precautions to take against the event. For example, the Homeland Security Department may send out information about the procedures for dealing with nuclear, biological, and chemical events.
Moreover, different types of alert messages may be sent based on the type of events that occurred. For example, short message type 1 (SMS1) may be sent for a general event, while short message type 2 (SMS2) may be sent for a more serious event. In addition, one or more types of messages may be sent simultaneously to a mobile device based on the type of events. For example, in an event of abduction, a text containing a license number and description of the abductor may be sent simultaneously with a picture of the abductee and a map of the abduction location.
In addition to initiating event monitoring by an event monitor or a person involved in the event, mobile users may register for monitoring of events and delivery of alert messages when the events occur. FIG. 8 provides a flowchart of an exemplary method for providing information to mobile device who initiated event monitoring. Process 800 begins at step 802 with a mobile user registering a location and/or type of event to be monitored. For example, a mobile user may register to monitor for a traffic accident at a particular intersection.
Next, process 800 continues to step 804 to monitor for the specific event. Process 800 continues to step 806 to determine if the event is a specific event based on the type and/or location of the event detected. This step may be accomplished by utilizing the GIS/GPS system and image recognition software. If the event is the specific event based on the location and/or type of the event detected, process 800 continues to step 808 to send messages alerting the event either directly or indirectly to the mobile device of the registered user. Otherwise, the process terminates thereafter.
In summary, aspects of the present disclosure provide a method and system for providing information to mobile device based on an event at a geographical location. Events may be detected from sensors or reporting of the event by a person. Also, a mobile user may register and initiate event monitoring. Alerting of the events may be performed directly or indirectly. Alert messages may be sent directly to mobile devices that are associated with service provider sites in various geographical locations. Alert messages may also be sent first to the service provider sites or other systems, which then forward the messages to associated mobile devices. Event information may be stored in a repository or database or within the service provider sites. Aspects of present disclosure may utilize image recognition software and GIS/GPS servers to identify a location and a type of the event, such that a determination can be made as to whether the event is a specific event. In this way, alert messages may be sent to specific mobile devices at or near the geographical location of the event.
Systems and methods have been shown and/or described in the above embodiments for alerting events to mobile users based on geographical locations. Although the above descriptions set forth preferred embodiments, it will be understood that there is no intent to limit the invention by such disclosure, but rather, it is intended to cover all modifications and alternate implementations falling within the spirit and scope of the invention. Furthermore, the embodiments are intended to cover capabilities and concepts whether they be via a loosely coupled set of components or they be converged into one or more integrated components, devices, circuits, and/or software programs. | A system, method, and non-transitory computer readable medium comprising instructions for receiving information about an event from at least one mobile device, the information comprising location information and event type information and identifying the event based on the information, the event being identified by associating the event type information with a specific event and associating the location information with a particular location associated with the specific event. | 7 |
TECHNICAL FIELD
[0001] The present invention relates to a method and a system for secure encrypted transmission or authentication between at least two units via an insecure communication channel.
BACKGROUND
[0002] Normally, it is difficult to achieve secure encrypted transmission via insecure communication channels, such as public telephone lines, data networks, in radio-transmission operations, and so on. Conventional encrypting algorithms require that keys in the form of private or public keys be transmitted between the units. Such key transmission does, however, cause practical problems. The keys may be transmitted on separate secure channels, but this solution is inconvenient, expensive and time-consuming. Alternatively, the keys may be transmitted via the insecure channel on which the encrypted message is then to be transmitted. However, this procedure involves a security risk. Also when encrypting systems having so called open keys are used, such as the RSA system, the transmission of the key means that larger and more complex keys and encrypting algorithms are required in order to ensure that the encrypted transmission is sufficiently secure, which naturally involves increased inconvenience and costs.
[0003] Similar problems are encountered in order to provide secure verification of units, so called authentication, via insecure communication channels. Such authentication is based on transmission between the units of data that are based on a unique key. For example, the key may be used to encrypt a check sum based on a transmitted or received message. Also in this case one is confronted with the same problems as those found in other encrypted transmission in the case of transmission of keys between the units.
OBJECT OF THE INVENTION
[0004] Consequently, one object of the present invention is to provide a method and a system of encrypted transmission and authentication via an insecure communication channel that completely or at least partly solve the above stated problems found in the prior-art technology.
[0005] This object is achieved by means of a method and a system as defined in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The invention will be described in more detail in the following with the aid of one embodiment and with reference to the appended claims, wherein:
[0007] [0007]FIG. 1 is a schematic view of a key-generating unit in accordance with one embodiment of the invention; and
[0008] [0008]FIG. 2 is a flow chart for performing encrypted transmission or authentication in accordance with one embodiment of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0009] The invention relates to a system for secure encrypted transmission/authentication between at least two units via an insecure communication channel. The communication channel could be any channel via which data may be transmitted, and more specifically, the channel could be stationary as well as wireless. Each such unit comprises a key-generating unit 1 , as shown in FIG. 1. This kind of key-generating units comprise a memory 10 , wherein identical original values U, so called seeds, have been stored, preferably in a dynamic and /inter-/exchangeable manner. The storage of original values preferably is effected in connection with the introductory initiation of the units, and advantageously it could be effected via a secure channel. Possibly, the original values need not, however, be transmitted physically but instead the users of the units concerned may themselves input an agreed-upon value. In addition, the original values may be exchanged, when needed, but alternatively the same original values are used for the duration of the entire life of the key-generating unit. In this case the original values need not be stored in dynamic memories, but instead permanent memories may be used.
[0010] In addition, the key-generating units comprise a counter to periodically change a counting value R, and a calculating unit adapted to generate, in each and every unit and independently of other units, a key based on the original value, and a counting value issued by the counter. Advantageously however, the counter and the calculating unit may be integrated in the same unit 11 , which advantageously may be a micro-processor, such as a commercially available CPU. The counter may advantageously be controlled by an oscillator or a clock, which could likewise be integrated in unit 11 . Preferably a real-time-based clock, which is integrated with the CPU 11 , is used. In addition, the counter is increased stepwise by integers, whereby it becomes easier to keep the units in phase with one another (synchronised).
[0011] Provided that the same original values are stored in the memory 10 and that the counters are synchronised to deliver the same counting value, identical keys may be generated in several key-generating units, independently of one other. These keys may then be used for encrypting or authenticating purposes between the units.
[0012] Furthermore, the key-generating units preferably are adapted to sense whether they are synchronised or not, and in case they are not, to implement this synchronisation. Sensing may be performed by means of a particular synchronising test that is performed prior to the generation of keys. Alternatively, a need for synchronisation may, however, be identified when different keys are used, and only thereafter may synchronisation resetting be effected. Synchronisation may be effected for example by exchange of counting values between the units.
[0013] The calculating unit comprises a calculating algorithm F, which uses the original value and the counting value as input parameters, i.e. F=f(R,U). This calculating algorithm preferably is implemented in hardware in the calculating unit, or alternatively it is stored in a non-dynamic and unchangeable memory. The calculating algorithm preferably generates a 128-bit key, but keys of other lengths are of course also conceivable. Every time an order is given to the key generator to produce a new key therefore a new pseudo-random 128-bit word is generated, which is calculated on the basis of the “seed” and the counting value.
[0014] The key-generating unit 1 further comprises an interface part 12 serving to enable communication between the communicating unit and the key-generating unit. Preferably, this communication comprises emission of instructions to the key-generating unit to generate a key and the emission of a thus generated key back to the communicating unit.
[0015] Advantageously the key-generating unit is implemented in hardware and executed in the form of an integrated circuit, thereby making it more difficult to tamper with. This circuit may then be added to and used together with essentially any type of communicative unit. For example, it is possible to use the key-generating unit in accordance with the invention together with rechargeable cards, so called smart cards, in portable or stationary computers, in mobile telephones, electronic calendars and similar electronic equipment that is communicative.
[0016] However, it is likewise possible to implement the key-generating unit in software for example in a conventional computer, and to use existing memories and the like. This alternative is particularly advantageous for implementation in stationary units, and in particular units that are used as central units.
[0017] The key-generating units in accordance with the invention may be used either for point-to-point communication or authentication, i.e. between two units, or between a central unit, a server, or several users, clients. Such a central unit preferably comprises a plurality of different key-generating units, one for each client in communication with the central unit. Alternatively, a key unit could comprise several different original values, in which case the command to the key-generating unit to generate a key also comprises information regarding which original value should be used. It is likewise possible for several units that communicate with the central unit to have identical key-generating units, enabling them to communicate with the same key-generating unit in the central unit.
[0018] In the case of a central unit, adapted to communicate with several other units, the central unit preferably comprises a means for software implementation of the key generation unit whereas the clients have hardware implemented means. For example, the clients could be smart cards or mobile telephones, computers and the like. Thus, the system in accordance with the invention may be used between a bank and its clients, between enterprises and their employees, between a company and its subsidiaries, and so on. In addition, the system may be used to control access to home pages via Internet or the like, for example by connecting its smart card to a reader provided for that purpose, and in this manner it becomes possible also to control the access to electronic equipment that communicates wireless for example via Blue-tooth.
[0019] Also units that are not central units may comprise several original values, in the same key-generating device or in separate units, in order to communicate via several separate channels. In this manner the unit may be used for communication with several different central units. For example, a smart card may be used for communication with several different banks or other establishments.
[0020] In the following an encrypted transmission or authentication with the aid of the system of the invention will be described with reference to FIG. 2. In a first step S 1 , the units intended for future intercommunication are initiated, in which process they are provided with identical original values and preferably are also synchronised. The system is now ready for use, and at a later time, which may occur after the lapse of an arbitrary period of time after the initiation, the units are interconnected via an insecure communication channel (step S 2 ), and at least one of the unit identifies itself to the other (step S 3 ). In step S 4 , the other unit determines whether the identity given is known and whether it has a corresponding key-generating circuit, i.e. a key-generating circuit as defined above and with a corresponding original value. If this is the case, the process proceeds to step S 5 , otherwise the process is interrupted.
[0021] The units then agree to execute encrypted transmission or authentication, whereby each one separately calculates keys in the respective key-generating unit (step S 8 ). Before this happens, a synchronisation test (S 6 ) might have been made to investigate whether the counters in the respective key-generating units are synchronised. If this is the case, the process continues directly to step S 8 , otherwise a synchronisation step (S 7 ) is first executed to reset the inter-unit synchronisation. Step S 7 could, however, alternatively be omitted and the process of identifying that the units are no longer synchronised could instead be effected by reckoning that identical keys have not been used. In this case, the process thereafter executes the synchronisation step S 7 and then returns to step S 8 in order to again calculate keys in the respective units.
[0022] The calculated keys are then used to execute encrypted transmission or authentication. It should be understood, however, that encrypted transmission and authentication of course may be effected simultaneously and in the same process. Encrypting and authentication may be effected with the aid of essentially any encrypting algorithm that uses keys, as the known RFSM and RSA algorithms.
[0023] The invention may be used for authentication, i.e. verification that the unit with which one communicates is the one it claims to be, as well as for key-generation for encrypted transmission purposes. The units that are used in connection with the present invention, such as smart cards, telephones and the like, could however advantageously be equipped with means arranged to ensure that the unit user is the correct one, i.e. authentication between users and the communicating unit. Such authentication may be effected with the aid of input of a code, identification of finger-prints and the like.
[0024] The system and the method in accordance with the invention provides a simple and inexpensive way of achieving a high degree of security in encrypted transmission and authentication, since the invention makes it possible to create the same key synchronously in two different places and without exchange of information, or possibly with exchange of information as to which key in the sequence is to be created, i.e. the counting value. Consequently, no keys need be exchanged to execute authentication or encrypted transmission between two units, such as between a server and a client, or vice versa. This makes it possible to use shorter keys as well, which provides for less expensive and more efficient transmission while at the same time security is maintained or even is increased in comparison with conventional systems. Thanks to the invention a large portion of the security means may to a large extent be hardware-integrated, which increases the security even more, since preferably in this case only the seed is exchangeable and normally only the generated keys are accessible from outside.
[0025] Several varieties of the system and the method described above are possible. For example, the method and the system do not depend on the encrypting or authentication method used but may be used in a simple and secure manner to generate keys, and consequently it may be used together with most known methods of this kind. In addition, the key-generating unit preferably is implemented in hardware, which makes the key-generating process completely hidden to the user. It is, however, also possible to implement the key-generating unit in software in an ordinary computer. In addition, the units in the system may be essentially any communicative electronic units. The counters used to generate the counting values for the key-generating units could also be of any type, provided that they generate counting values that vary with time. It is likewise possible to omit counters in one or several units, and in this case the step of synchronising the counters is replaced by a step involving exchange of counting values between the units, i.e. to synchronise the counting values, before each key-generating operation. Such and other obvious varieties must be regarded to be within the scope of protection of the invention as the latter is defined in the appended claims. | A method and a system for encrypted transmission or authentication between at least two units via an insecure communication channel, comprising the steps of: (a) in an initiation procedure, producing a common original value to be used in the respective units; (b) synchronising a counting value in each unit; (c) generating a key on the basis of the original value and the counting value in each unit, independently of other units; and (d) using the thus generated key in a subsequent encrypted transmission or authentication operation. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Patent Application No. 62/276,080 filed on Jan. 7, 2016, which is incorporated herein by reference.
BACKGROUND
[0002] In the process of rotary drilling a well, a wellbore fluid or mud is circulated down the rotating drill pipe, through the bit, and up the annular space between the pipe and the formation or steel casing, to the surface. The wellbore fluid performs many different functions. For example, it removes cuttings from the bottom of the hole to the surface, suspends cuttings and weighting material when the circulation is interrupted, controls subsurface pressure, isolates the fluids from the formation by providing sufficient hydrostatic pressure to prevent the ingress of formation fluids into the wellbore, cools and lubricates the drill string and bit, maximizes penetration rate, etc. An important objective in drilling a well is also to secure the maximum amount of information about the type of formations being penetrated and the type of fluids or gases in the formation. This information is obtained by analyzing the cuttings and by electrical logging technology and by the use of various downhole logging techniques, including electrical measurements.
[0003] Various logging and imaging operations are performed during or after the drilling operation, for example, they may be performed while drilling in the reservoir region of an oil/gas well in order to determine the type of formation and the material therein. Such information may be used to optimally locate the pay zone, i.e., where the reservoir is perforated in order to allow the inflow of hydrocarbons into the wellbore. The use of wireline well logs is well known in the art of drilling subterranean wells and in particular oil and gas wells. A wireline log is generated by lowering a logging tool down the well on a wireline. The tool is slowly brought back to the surface and the instruments on the logging tool take measurements that characterize the formation penetrated by the well in addition to other important properties of the well. For example, during logging wireline logs may use measurements of relative resistivity of the formation to determine the geological composition of the downhole formation. An alternative or supplement to wireline logging involves logging tools placed in a specialized drill collar housing and run in the drill string near the bit. This technique is known as logging-while-drilling (LWD) or formation-evaluation-while-drilling (FEWD). Measurements such as electrical resistivity may be thereby taken and stored down-hole for later retrieval during a “tripping out” of the drill string, or transmitted to the surface via mud-pulse telemetry. Also, during drilling, such resistivity measurements may be useful to determine the location of the drill bit to enhance geosteering capabilities and directional drilling control, collected such as by a measurement while drilling (MWD) tool. Thus, electrical logs and other wireline log techniques are depended upon in the oil and gas exploration industry to determine the nature of the geology and the reservoir properties of the petroleum bearing formations penetrated by the well, as well as other properties of the drilling process (e.g., the location of the drill bit). Further, such well logs are often the only record of a formation penetrated by a well that are available for correlation amongst different wells in a particular field.
SUMMARY
[0004] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
[0005] In one aspect, embodiments disclosed herein relate to a method of electrically logging a section of a wellbore that includes circulating a wellbore fluid within the wellbore, the wellbore fluid including a base fluid; and a crosslinked and branched polymeric fluid loss control agent formed from at least an acrylamide monomer and a sulfonated anionic monomer; wherein the fluid loss control agent has an extent of crosslinking that is selected so that the fluid loss control agent has a viscosity that is within a peak viscosity response of the viscosity response curve; placing within the wellbore a wellbore logging tool capable of applying an electrical current to the wellbore; applying electrical current from the logging tool; and collecting an electrical log of the portion of the wellbore that has had electrical current applied thereto.
[0006] In another aspect, embodiments disclosed herein relate to a system for electrically logging a section of a wellbore that includes a wellbore containing a wellbore fluid, the wellbore fluid including a base fluid; and a crosslinked and branched polymeric fluid loss control agent formed from at least an acrylamide monomer and a sulfonated anionic monomer, wherein the fluid loss control agent has an extent of crosslinking that is selected so that the fluid loss control agent has a viscosity that is within a peak viscosity response of the viscosity response curve; and a wellbore logging tool capable of applying an electrical current to the wellbore.
[0007] In yet another aspect, embodiments disclosed herein relate to a method of electrically logging a section of a wellbore that includes circulating a wellbore fluid within the wellbore, wherein the wellbore fluid exhibits low end rheology that does not deviate by more than 30 percent under a temperature up to 300° F. when compared to low end rheology of the fluid at temperatures below about 250° F.; placing within the wellbore a wellbore logging tool capable of applying an electrical current to the wellbore; applying electrical current from the logging tool; and collecting an electrical log of the portion of the wellbore that has had electrical current applied thereto.
[0008] Other aspects and advantages of the claimed subject matter will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0009] FIG. 1 shows a wellbore extending vertically into a formation with a resistivity logging tool located therein.
[0010] FIG. 2 shows an enlarged perspective view, partly in section, of a portion of the sonde of the resistivity tool.
DETAILED DESCRIPTION
[0011] Embodiments disclosed herein generally relate to methods of using wellbore logging, and more specifically resistivity tools, to interrogate wellbores having a thermally stable water based wellbore fluid therein. In particular, one or more embodiments disclosed herein relate to methods of using resistivity tools to interrogate wellbores having conductive wellbore fluids therein, particularly reservoir drill-in-fluids (RDF) that include synthetic copolymeric fluid loss agents.
[0012] Reservoir drill-in-fluids are a specialty fluid having a limited amount of solids and often degradable polymeric additives and may be used when drilling through the reservoir section of a wellbore. Wellbore fluids in accordance with the present disclosure may contain polymeric fluid loss control additives that are capable of withstanding HTHP conditions, yet clean up with breaker fluids and be suitable for clean drilling and reservoir drill-in applications. During standard wellbore operation, wellbore fluids are often formulated with a number of polymeric additives to tune the viscosity and gel strength of the fluid such that wellbore fluids maintain the ability to suspend particulate additives and drill cuttings, particularly when circulation is stopped. Another function of the drilling fluid is its ability to seal permeable formations exposed by the bit with a low permeability filter cake. Seals are often by created by wellbore fluid additives such as polymers or bridging agents accumulating to form a filter cake on the walls of the wellbore.
[0013] However, rheological characteristics of wellbore fluids may be difficult to control because of the adverse conditions under which wellbore fluids are used, including high temperature, high shear (caused by the pumping and placement), high pressures, and low pH. For example, when drilling of certain deep wells, e.g., greater than 15,000 feet, or in geothermally active formations, temperatures may be such that thermal decomposition of certain drilling fluid additives occurs, which can cause detrimental changes in viscosity and flow characteristics that can negatively affect the overall drilling operation, not to mention any logging operations that may be done after drilling.
[0014] For example, if a wireline log is to be taken of a wellbore after it is drilled, the drill string must be tripped out of the wellbore before the wireline can be inserted. Tripping out the drill string can be a time consuming process and during this process the wellbore fluid present in the wellbore is subject to HTHP and static conditions. Under HTHP conditions, polymeric materials used to viscosity conventional wellbore fluids and provide a measure of fluid loss control may degrade, causing changes in the rheology of the fluid. Specifically, exposure to HTHP conditions can have a detrimental effect on viscosifying agents, resulting in a loss in viscosity of the fluid at high temperatures. A breakdown of the rheology can limit or eliminate the ability of the wellbore fluid to suspend solids entrained within it (such as weighting agents, bridging agents or drill cuttings) and may lead to settlement, loss in fluid density, possible blowout of the well, situations that could impede the collection of a wellbore log by wireline.
[0015] Specialized additives for HTHP conditions often contain polymeric materials that have exceptional resistance to extreme conditions, but can require specialized cleanup fluids to remove. For example, many cellulose and cellulose derivatives used as viscosifiers and fluid loss control agents degrade at temperatures around 200° F. and higher. Hydroxyethyl cellulose, on the other hand, is considered sufficiently stable to be used in an environment of no more than about 225° F. (107° C.). Likewise, because of the high temperature, high shear, high pressures, and low pH to which well fluids are exposed, xanthan gum is considered stable to be used in an environment of no more than about 290 to 300° F. (143 to 149° C.). However, the relative thermal stability of polymers such as xanthan gum may also contribute to decreased well productivity. As a result, expensive and often corrosive breaker fluids have been designed to disrupt filter cakes and residues left by these polymers, but beyond costs, the breakers may also result in incomplete removal and may be hazardous or ineffective under HTHP conditions.
[0016] In some embodiments, wellbore fluid additives in accordance with the present disclosure may also exhibit enhanced high temperature stability and cleanup properties, allowing for their use as brine viscosifiers and fluid loss additives in wellbore operations that may be sensitive to the amount of formation damage caused by standard drilling fluid additives. To this end, wellbore fluids in accordance with the present disclosure may be used in drilling (particularly the reservoir section) and/or to treat fluid loss in some embodiments, for example, by formulating a drilling fluid or fluid loss pill with a crosslinked fluid loss control additive. Further, advantages of wellbore fluids in accordance with the present disclosure are that they may retain their rheology and stability during the tripping out process required to remove the drill bit and complete a wireline log of the wellbore.
[0017] Wireline Logging
[0018] When an electrical wireline log is made of a well, electrodes on the well logging tool are conventionally in contact with the wellbore fluid or filtercake and hence the formation rocks through which the well has penetrated. An electrical circuit is created and the resistance and other electrical properties of the circuit may be measured while the logging tool is withdrawn from the well. In conventional wellbore logging, the measurement of resistivity requires the presence of a highly conductive path between the logging tool and the formation (i.e., through the wellbore fluid). The resulting data is a measure of the electrical properties of the drilled formations versus the depth of the well. The results of such measurements may be interpreted to determine the presence or absence of petroleum or gas, the porosity of the formation rock, and other important properties of the well. In one or more embodiments, the measurements once taken may be stored downhole with the wellbore tool that took them or they may be transmitted to the surface during their collection.
[0019] Referring now to FIG. 1 , a schematic of a wellbore and tool that may be used in accordance with certain aspects of the present disclosure is shown. FIG. 1 shows a wellbore 10 extending vertically into a formation 12 with a resistivity logging tool 20 located therein. The wellbore 10 has a generally cylindrically shaped exposed wall 14 upon which a filtercake will form as a wellbore fluid permeates the formation 12 during a drilling or other wellbore formation. A wellbore fluid 16 may be present in the wellbore 10 during the logging of the wellbore.
[0020] The resistivity logging tool 20 may be suspended in the wellbore 10 by a pulling cable 22 , which at its upper end extends around sheaves 23 and 24 to the spool 26 of a winch 28 . The spool of the winch 28 can be rotated in either direction, to either raise or lower the tool 20 , by operator control of an engine 30 in the winch-carrying vehicle 32 . Sheave 23 is typically supported from a derrick frame 38 centered over the wellbore 10 . On the winch-carrying vehicle 32 there is also located electronic apparatus 40 , which permits control of the various operations during a logging run, as well as providing signal processing and storage of the signals from the tool 20 .
[0021] The resistivity logging 20 tool itself may comprise a sonde 41 and an electronic cartridge 44 , connected to each other by an articulated physical connection 43 . Centering of the resistivity logging tool 20 in the wellbore 10 may be facilitated by bowed-spring centralizers 42 , which may comprise four equiangularly spaced spring bow members extending radially outward towards the wellbore wall 14 .
[0022] Moving now to FIG. 2 which shows an enlarged perspective view, partly in section, showing more clearly a portion of the sonde 41 of the resistivity tool 20 . Four pads 46 , each having an array of electrodes 49 thereon, are each mounted on a pair of supports 47 , which urge the pads 46 outwardly against the wellbore wall 14 , by spring action or hydraulic pressure in a manner known in resistivity measuring systems. The method for obtaining the desired resistivity measurements using such a system as described above is to use the array of electrodes 49 on the pads 46 to apply an alternating current through the formation to a return electrode, which may be the housing of the electronic cartridge 44 . As the current emerges from the electrodes 49 on the pads 46 , its path is initially focused on the small volume of formation 12 directly facing the respective electrodes 49 but expands rapidly, in a magnitude dependent upon the properties of the formation, through the wellbore wall 14 and across the formation between the electrodes 49 and the return electrode. These measurements occur continuously as the resistivity tool 20 is dragged upwardly in the wellbore 10 and are called microresistivity measurements because they measure the electrical resistivity of very small vertical segments of the wellbore wall 14 and formation 12 structure.
[0023] As will be understood by a skilled artisan, the resistivity tool shown in FIGS. 1 and 2 may be configured in a variety of ways and have a variety of different components. Its inclusion here is not meant to limit the scope of the application in any way and is only intended to represent the basics of the process of obtaining an electrical log or resistivity measurement in a wellbore. For example, similar equipment and techniques may be used to acquire electrical logs in highly deviated wellbores. Additionally, similar equipment and techniques may be used where the pads are not placed in contact with the formation and instead the measurement is taken by application of the current through the wellbore fluid itself.
[0024] Wellbore Fluids
[0025] Wellbore fluid formulations in accordance with the present disclosure may contain crosslinked polymeric fluid loss control agents that may include a copolymer formed from at least one acrylamide monomer and at least one sulfonated anionic monomer. In other embodiments, crosslinked and branched fluid loss control agents may also include higher order copolymers and block copolymers such as terpolymers, quaternary polymers, and the like, including at least one acrylamide monomer, at least one sulfonated anionic monomer, and optionally other monomers as well.
[0026] In one aspect, wellbore fluids of the present disclosure incorporate a crosslinked and branched polymeric fluid loss control agent that is formed from at least an acrylamide monomer and a sulfonated anionic monomer. In one or more embodiments, crosslinked and branched fluid loss control agents may include polymers and copolymers synthesized from a mixture of monomers that may include acrylamide-based monomers. Acrylamide-based monomers in accordance with the present disclosure may play a role in creating an effective and high temperature stable fluid loss control agents, enhancing the fluid's high temperature endurance. In addition to unsubstituted acrylamide monomers, acrylamide-based monomers may also include N-substituted acrylamides, such as alkylacrylamides, N-methylol, N-isopropyl, diacetone-acrylamide, N-alkyl acrylamide (where alkyl is C 1 to C 14 ), N,N-dialkyl acrylamides (where alkyl is C 1 to C 14 ), N-cycloalkane acrylamides, combinations of the above and related compounds.
[0027] The crosslinked fluid loss control agents may also contain one or more sulfonated anionic monomers. While not limited to a particular theory, incorporation of anionic monomers may increase stability when added to a copolymer by repelling negatively charged hydroxide ions that promote hydrolysis of the acrylamide moiety of the polymer. Sulfonated anionic monomers, such as 2-acrylamide-2-methyl-propanesulfonic acid (AMPS®), a trademark of the Lubrizol Corporation—also referred to as acrylamide tertiary butyl sulfonic acid (ATBS), vinyl sulfonate, styrene sulfonic acid, and the like, may provide tolerance to divalent cations such as calcium and magnesium encountered in drilling fluids. Thus, the incorporation of sulfonated anionic monomers may result in an improved thermally stable fluid loss control agent for divalent cation systems, including brine based drilling fluids. Depending upon the reactivity ratio and the end use of the polymer, other sulfonated monomers may also be utilized for preparing an effective fluid loss control agent.
[0028] Further, it is also within the scope of the present disclosure that other monomers can be incorporated into the crosslinked polymer composition depending upon the end use of the polymer or the type of aqueous base drilling fluid. For example, lipophilic monomers, such as isobornyl methacrylate, 2-ethyl hexyl acrylate, N-alkyl and N,N-dialkyl acrylamide, styrene and the like can be incorporated to improve the performance of the polymer in high brine containing drilling fluids. Also, to make it more tolerant to other electrolytes, anionic monomers, such as maleic acid, tetrahydrophthalic acid, fumaric acid, acrylic acid and the like can be incorporated into the crosslinked polymers.
[0029] In one or more embodiments, crosslinked fluid loss control agents may contain covalent intermolecular crosslinking depending on the desired functional characteristics of the polymer. In one or more embodiments, the extent of crosslinking may be selected to maximize the viscosity of the resulting polymer in solution. In one or more embodiments, a crosslinked fluid loss control agent may exhibit a bell-curve type response for its viscosity in solution as the quantity of crosslinker used to crosslink the co-polymer is increased. That is, the viscosity initially increases as the quantity of crosslinker (and thus the crosslinks) are increased until a peak viscosity is reached, at which point the viscosity decreases and eventually results in a substantially zero slope as the quantity of crosslinker is further increased. In one or more embodiments, the crosslinked fluid loss control agent used in the RDF may be synthesized with an amount of crosslinker, and thus extent of crosslinking, so that its viscosity response is in the higher viscosity region of the bell-curve described above. For example, in one or more embodiments, the extent of crosslinking in the crosslinked fluid loss control agent may be selected so that the viscosity of fluid loss control agent is within a peak viscosity response of the viscosity response curve (created by plotting viscosity as a function of crosslinker under otherwise constant conditions). In one or more embodiments, the peak viscosity response may be defined as the amount of crosslinker that correlates to the peak amount plus or minus the amount of crosslinker that correlates to up to 75% of the area under the viscosity response curve that terminates upon reaching substantially zero slope. In more particular embodiments, the amount of crosslinker may be that which correlates to within 50%, or in some embodiments 25%, of the area under the viscosity response curve.
[0030] In one or more embodiments, the peak viscosity response may be expressed as the the amount of crosslinker that correlates to the peak amount plus or minus the amount of crosslinker that correlates to 1.5 standard deviations from the peak amount. In more particular embodiments, the amount of crosslinker correlates to the peak amount plus or minus the amount of crosslinker that correlates to 1.0 standard deviations from the peak amount or from 0.5 standard deviations in even more particular embodiments. Further, in one or more embodiments, the peak viscosity response may be expressed as the amount of crosslinker that correlates to the peak amount plus or minus 50% of the peak amount. In more particular embodiments, the amount of crosslinker is the peak amount plus or minus 30% or 20% of the peak amount. Further, based on the above, one of ordinary skill in the art would appreciate that the breadth of the amount of crosslinker (and selection of amount of crosslinker) may depend, for example, on the shape of the viscosity response curve and the desired rheological properties for the wellbore fluid and its particular application.
[0031] Crosslinking may be achieved, for example, by incorporation of crosslinking monomers such as methylenebisacrylamide, divinyl benzene, allylmethacrylate, tetra allyloxethane or other allylic bifunctional monomers. The crosslinked fluid loss control agent may have a percentage of intermolecular crosslinking that ranges from 0.25% to 10% in some embodiments, from 0.5% to 5% in other embodiments, and from 0.75% to 2.5% in other embodiments.
[0032] Wellbore fluids of the present disclosure may also exhibit temperature stability up to 250° F. (121° C.) in some embodiments, or greater that 250° F. (121° C.) in other embodiments. For example, in one or more embodiments, wellbore fluids of the present disclosure may exhibit temperature stability up to 300° F., or up to 350° F., or up to 400° F., or up to 450° F. Temperature stability may be described herein as the ability of the fluid to maintain suitable rheology at the temperature indicated above for at least five days. In one or more embodiments, a wellbore fluid of the present disclosure may exhibit low end rheology (i.e., rheology at 3 and 6 rpm) that does not deviate by more than 30 percent under the elevated temperature conditions indicated above when compared to the low end rheology at temperatures below about 250° F. In one or more embodiments, the rheology at 3 rpm, when tested at 120° F., for fluids according to the present disclosure may be at least 5 under any of the temperature conditions described above. In one or more embodiments, crosslinked fluid loss control additives may be added to a wellbore fluid at a concentration that that ranges from a lower limit selected from the group of 0.5, 1, 2.5, and 3 lb/bbl, to an upper limit selected from the group of 5, 10, 12, and 15 lb/bbl, where the concentration may range from any lower limit to any upper limit. The amount needed will vary, of course, depending upon the type of wellbore fluid, contamination, and temperature conditions.
[0033] In one or more embodiments, the polymeric fluid loss control agent may have an average molecular weight that ranges from a lower limit selected from the group of 250, 500, and 1,000 Da, to an upper limit selected from the group of 100, 250, 500, and 1,000 kDa, where the molecular weight may range from any lower limit to any upper limit. As used herein, molecular weight refers to weight average molecular weight (M w ) unless indicated otherwise.
[0034] In one or more embodiments, crosslinked fluid loss control agents may be a copolymer having a ratio of acrylamide monomer and sulfonated anionic monomer that ranges from 0.5:1 to 10:1. In some embodiments, a ratio of acrylamide monomer and sulfonated anionic monomer may range from 1:1 to 5:1
[0035] Base Fluids
[0036] In one or more embodiments, crosslinked fluid loss control additives and/or crosslinked polyvinylpyrrolidones in accordance with the present disclosure may be hydrated by their simple addition to a base fluid. For example, the crosslinked fluid loss control additives may be hydrated by free water upon their addition to water or a brine used a base fluid. In one or more embodiments, the fluid of the present disclosure may have an aqueous base fluid, the fluid being a monophasic fluid, in which the above mentioned polymers are included. The aqueous medium of the present disclosure may be water or brine. In those embodiments of the disclosure where the aqueous medium is a brine, the brine is water comprising an inorganic salt or organic salt. The salt may serve to provide desired density to balance downhole formation pressures, and may also reduce the effect of the water based fluid on hydratable clays and shales encountered during drilling. In various embodiments of the drilling fluid disclosed herein, the brine may include seawater, aqueous solutions wherein the salt concentration is less than that of sea water, or aqueous solutions wherein the salt concentration is greater than that of sea water. Salts that may be found in seawater include, but are not limited to, sodium, calcium, aluminum, magnesium, zinc, potassium, strontium, and lithium, salts of chlorides, bromides, carbonates, iodides, chlorates, bromates, formates, nitrates, oxides, phosphates, sulfates, silicates, and fluorides. Salts that may be incorporated in a brine include any one or more of those present in natural seawater or any other organic or inorganic dissolved salts.
[0037] In some embodiments, the fluid may be a divalent halide is selected from the group of alkaline earth halides or zinc halides. The brine may also comprise an organic salt, such as sodium, potassium, or cesium formate. Inorganic divalent salts include calcium halides, such as calcium chloride or calcium bromide. Sodium bromide, potassium bromide, or cesium bromide may also be used. The salt may be chosen for compatibility reasons, i.e. where the reservoir drilling fluid used a particular brine phase and the completion/clean up fluid brine phase is chosen to have the same brine phase.
[0038] Additives
[0039] In one embodiment, the drilling fluid of the disclosure may further contain other additives and chemicals that are known to be commonly used in oilfield applications by those skilled in the art. A variety of additives can be included in the aqueous based drilling fluid of this disclosure with the purpose of formation of a thin, low permeability filter cake which seals pores and other openings in the formations which are penetrated by the bit. Such additives may include thinners, weighting material, gelling agents, shale inhibitors, pH butters, etc.
[0040] Wellbore fluids of the present disclosure may contain other materials needed to form complete drilling fluids. Such other materials optionally may include, for example: additives to reduce or control low temperature rheology or to provide thinning, additives for enhancing viscosity, additives for high temperature high pressure control, and emulsion stability.
[0041] Examples of wellbore fluid thinners that may be used include lignosulfonates, lignitic materials, modified lignosulfonates, polyphosphates and tannins. In other embodiments low molecular weight polyacrylates can also be added as thinners. Thinners are added to a drilling fluid in order to reduce flow resistance and gel development. Other functions performed by thinners include the reduction of filtration and cake thickness, to counteract the effects of salts, to minimize the effects of water on the formations drilled, to emulsify oil in water, and to stabilize mud properties at elevated temperatures.
[0042] The HTHP wellbore fluids of the present disclosure additionally include an optional weighting material, sometimes referred to as a weighting agent. The type and quantity of weighting material used may depend upon the desired density of the final drilling fluid composition. Weight materials include, but are not limited to: barite, iron oxide, calcium carbonate, magnesium carbonate, and combinations of such materials and derivatives of such materials. The weight material may be added in a quantity to result in a drilling fluid density of up to 24 pounds per gallon. In an embodiment, the particulate weighting agent may be composed of an acid soluble material such as calcium carbonate, magnesium carbonate, Mn 3 O 4 , etc.
[0043] The solid weighting agents may be of any particle size (and particle size distribution), but some embodiments may include weighting agents having a smaller particle size range than API grade weighing agents, which may generally be referred to as micronized weighting agents. Such weighting agents may generally be in the micron (or smaller) range, including submicron particles in the nanosized range. One of ordinary skill in the art would recognize that, depending on the sizing technique, the weighting agent may have a particle size distribution other than a monomodal distribution. That is, the weighting agent may have a particle size distribution that, in various embodiments, may be monomodal, which may or may not be Gaussian, bimodal, or polymodal.
[0044] In one or more embodiments, an amine stabilizer may be used as a pH buffer and/or thermal extender to prevent acid-catalyzed degradation of polymers present in the fluid. A suitable amine stabilizer may include triethanolamine; however, one skilled in the art would appreciate that other amine stabilizers such as methyldiethanol amine (MDEA), dimethylethanol amine (DMEA), diethanol amine (DEA), monoethanol amine (MEA), cyclic organic amines, sterically hindered amines, amides of fatty acid, or other suitable tertiary, secondary, and primary amines and ammonia could be used in the fluids of the present disclosure.
[0045] In some embodiments, the amine stabilizer may be commercially available amine stabilizers such as PTS-200, or polyether amines polyether amines such as the JEFFAMINE series of polyether amines including Jeffamine D-230, all of which are available from M-I L.L.C. (Houston, Tex.). Amine stabilizers may be added to a wellbore fluid in accordance with the present disclosure at a concentration that ranges from 0.1% to 10% by weight of the wellbore fluid in some embodiments, and from 0.5% to 5% by weight of the wellbore fluid in other embodiments. Further, is also envisioned that the fluid may be buffered to a desirable pH using, for example, magnesium oxide. The compound serves as to buffer the pH of the drilling fluid and thus maintain the alkaline conditions under which the process of hydrolysis or degradation of the polymers is retarded.
[0046] The fluids may be formulated or mixed according to various procedures; however, in particular embodiments, the polymeric fluid loss control agent of the present disclosure may be yielded in fresh water prior to be added to a brine (or vice versa). Thus, after the polymer yields in fresh water, a brine (such as a divalent halide) may be combined with the yielded polymer. The gelling agent may be added to the yielded polymer either before, after, or simultaneous with the brine.
[0047] Upon mixing, the fluids of the present embodiments may be used in drilling operations. Drilling techniques are known to persons skilled in the art and involve pumping a drilling fluid into a wellbore through an earthen formation. The fluids of the present embodiments have particular application for use in high temperature environments. The drilling fluid formulations disclosed herein may possess high thermal stability, having particular application for use in environments of up to 450° F. In yet another embodiment, the fluids of the present disclosure are thermally stable for at least 16 hours, or for at least two days, or for at least five days at the elevated temperatures indicated above.
[0048] One embodiment of the present disclosure involves a method of drilling a wellbore. In one such illustrative embodiment, the method involves pumping a drilling fluid into a wellbore during the drilling through a reservoir section of the wellbore, and then allowing filtration of the drilling fluid into the earthen formation to form a filter cake on the wellbore walls. The filter cake is partially removed afterwards, thus allowing initiation of the production of hydrocarbons from reservoir. The formation of such a filter cake is desired for drilling, particularly in unconsolidated formations with wellbore stability problems and high permeabilities. Further, in particular embodiments, the fluids of the present disclosure may be used to drill the reservoir section of the well, and the open hole well may be subsequently completed (such as with placement of a screen, gravel packing, etc.) with the filter cake remaining in place. After the completion equipment is installed, removal of the filter cake may be achieved through use of a breaker fluid (or internal breaking agent).
[0049] In one or more embodiments, the fluids of the present disclosure may also find utility in coiled tubing applications where the high temperature stability of the fluid could be useful. Coiled tubing applications use a long metal pipe that can be spooled on large reels in a variety of downhole operations including well interventions, production operations, and in some instances drilling. Many of the operations that use coiled tubing may also be done by wireline. However, coiled tubing has the advantage of being able to be pushed into the wellbore rather than the reliance on gravity with wireline and also fluids may be pumped through the coiled tubing. In embodiments where the fluids of the present disclosure are used in coiled tubing applications a lubricant may be added to the wellbore fluids to reduce friction although, the crosslinked fluid-loss control additive may effectively act as a friction reducer when used in coiled tubing applications.
Examples
Example 1—Tests of High Temperature Stability
[0050] In the following example, a wellbore fluid containing a branched and crosslinked AMPS acrylamide co-polymer was tested to determine its rheological properties and their stability at elevated temperatures. The wellbore fluid of Sample 1 was formulated as shown in Table 1. In Table 1, DEFOAM-X is a defoamer used for foam control and is available from MI-LLC (Houston, Tex.), ECF-1868 is a crosslinked AMPS acrylamide co-polymer available from M-I LLC (Houston, Tex.), SAFECARB is a calcium carbonate available from MI-LLC (Houston, Tex.) and is added to provide the fluid with bridging solids, MgO is added to act as a pH buffer for the fluid.
[0000]
TABLE 1
Formulation of Sample 1
Additives
Concentration
14.2 ppg CaBr 2 brine
0.57 bbl/bbl
Water
0.28 bbl/bbl
DEFOAM-X
0.35 ppb
ECF-1868
9.0 ppb
Dry CaBr 2
55.0 ppb
MgO
3.0 ppb
SafeCarb
81.0 ppb
[0051] To analyse the temperature stability of the Sample 1 formulation, a first portion of the fluid was hot rolled for 16 hours at 356° F., while a second portion was aged statically for 16 hours at 356° F., while a third portion was aged statically at 356° F. for 7 days. The rheology of the samples was measured with Fann 35 rheometer at a temperature of 120° F. as tabulated in Table 2.
[0000]
TABLE 2
Rheology of Sample 1
After 16 hours
After 7 days
Rheology
Fresh
After 16 hours hot
static
static aged
@ 120° F.
Fluid
rolled @ 356° F.
aged @ 356° F.
@ 356° F.
600
117
121
122
122
300
78
81
82
87
200
62
65
65
73
100
40
44
43
51
6
10
11
11
10
3
7
8
8
7
[0052] The fluid of Sample 1 that was hot rolled for 16 hours was also subjected to HTHP Fluid Loss testing and the results are shown in table 3 below.
[0000]
TABLE 3
Fluid Loss of Sample 1
Time (min)
New (ml)
Spurt
2.5
15
4.0
30
5.2
60
6.5
960 (16-hr)
18.0
[0053] In the following example, a wellbore fluid containing a branched and crosslinked AMPS acrylamide co-polymer was tested to determine its rheological properties and its stability at elevated temperatures. The wellbore fluid of Sample 2 was formulated as shown in Table 4. In Table 4, DEFOAM-X is a defoamer used for foam control and is available from MI-LLC (Houston, Tex.), ECF-1868 is a crosslinked AMPS acrylamide co-polymer available from MI-LLC (Houston, Tex.), SAFECARB is a calcium carbonate available from MI-LLC (Houston, Tex.) and is added to provide the fluid with bridging solids, PTS-200 is a pH-buffer and temperature stabilizer available from MI-LLC (Houston, Tex.), SAFE-SCAV NA is a liquid bisulfite-base additive available from MI-LLC (Houston, Tex.), SAFE-SCAV-HSW is an organic hydrogen sulfide scavenger and is available from MI-LLC (Houston, Tex.), CONQOR 303A is a corrosion inhibitor that is available from MI-LLC (Houston, Tex.), SP-101 is a sodium polyacrylate copolymer and is available from MI-LLC (Houston Tex.).
[0000]
TABLE 4
Formulation of Sample 2
Concentration
Products
(Lb/bbl.)
Dry NaCl
40.46
Water
286.37
DEFOAM-X
0.35
ECF 1868
6.0
PTS 200
3
SAFE-SCAV NA
0.1
SAFE-SCAV HSW
2
CONQOR 303A
2
SAFECARB 2
26
SAFECARB 10
24
Barite
80
SP 101
0.1
[0054] To analyse the temperature stability of the Sample 2 formulation, a first portion of the fluid was hot rolled for 16 hours at 380° F., while a second portion was hot rolled for 3 days at 380° F., while a third portion was aged statically for 3 days at 380° F., while a fourth portion was aged statically at 380° F. for 6 days. The rheology of the samples was measured with Fann 35 rheometer at a temperature of 120° F. as tabulated in Table 5.
[0000]
TABLE 5
Rheology of Sample 2
Temperature
120° F.
120° F.
120° F.
120° F.
120° F.
600 rpm
81
107
108
111
80
300 rpm
56
76
77
77
56
200 rpm
44
62
63
63
47
100 rpm
30
44
45
45
33
6 rpm
8
13
14
16
13
3 rpm
7
11
11
14
11
Gels 10″,
7
10
10
12
10
Lb/100 ft 2
Gels 10′,
7
11
10
13
11
Lb/100 ft 2
PV, cP
25
31
31
34
24
YP, Lb/100 ft 2
31
45
46
43
32
pH
9.46
9.30
9.30
9.20
9.20
[0055] In the following example, a coiled-tubing fluid containing a branched and crosslinked AMPS acrylamide co-polymer was tested to determine its rheological properties and its stability at elevated temperatures. The wellbore fluid of Sample 3 was formulated as shown in Table 6. In Table 6, DEFOAM-X is a defoamer used for foam control and is available from MI-LLC (Houston, Tex.), ECF-1868 is a crosslinked AMPS acrylamide co-polymer available from MI-LLC (Houston, Tex.), PTS-200 is a pH-buffer and temperature stabilizer available from MI-LLC (Houston, Tex.), DI-LOK is a fluid rheology stabilizer available from MI-LLC (Houston, Tex.).
[0000]
TABLE 6
Formulation of Sample 3
Products
Concentration
Dry NaCl
87.5
ppb
Water
0.871
bbl/bbl
DEFOAM-X
0.3535
ppb
ECF 1868
8.0
ppb
PTS 200
2.0
ppb
DI-LOK
5.0
ppb
[0056] To analyse the temperature stability of the Sample 3 formulation, a first portion of the fluid was hot rolled for 16 hours at 330° F., while a second portion was hot rolled for 48 hours at 330° F., while a third portion was aged statically for 16 hours at 330° F., while a fourth portion was aged statically at 330° F. for 48 hours. The rheology of the samples was measured with Fann 35 rheometer at a temperature of 120° F. as tabulated in Table 7.
[0000]
TABLE 7
Rheology of Sample 3
Fann-35
rheology
Fresh
Hot rolled at 330° F.
Static aged at 330° F.
@ 120° F.
Fluid
16 hours
48 Hours
16 hours
48 hours
600
76
87
87
77
78
300
53
61
60
52
54
200
42
49
48
42
43
100
29
34
34
28
30
6
9
0
10
8
9
3
7
8
8
6
7
PV
23
26
27
25
24
YP
30
35
33
27
30
pH
9.22
9.29
9.26
9.42
9.21
LSRV @
37199
35000
36492
30394
36292
0.0636 sec−1
@ 120° F.
using
Brookfield
viscometer
[0057] The rheology of the fluid of Sample 3 that was hot rolled at 330° F. for 16 hours was measured with a Fann 35 and Grace rheometer at several temperatures as tabulated in Table 8 below.
[0000]
TABLE 8
Rheology of Sample 3
120° F.
200° F.
250° F.
300° F.
330° F.
Fann 35
Grace
Grace
Grace
Grace
Grace
600
87
89
62
51
45
39
300
61
62
42
35
31
27
200
49
49
34
28
24
26
100
34
34
23
19
17
15
6
10
10
8
6
5
7
3
8
8
6
5
5
7
[0058] In the following example, a wellbore fluid containing a branched and crosslinked AMPS acrylamide co-polymer was tested to determine its rheological properties and its stability at elevated temperatures. The wellbore fluid of Sample 4 was formulated as shown in Table 9. In Table 9, ECF-1868 is a crosslinked AMPS acrylamide co-polymer available from MI-LLC (Houston, Tex.), PTS-200 is a pH-buffer and temperature stabilizer available from MI-LLC (Houston, Tex.), SAFE-SCAV-HS is an organic hydrogen sulfide scavenger and is available from MI-LLC (Houston, Tex.), CALOTHIN is a liquid anionic acrylic copolymer that provides rheology control and is available from MI-LLC (Houston, Tex.), and POROSEAL is a copolymer filtration control additive available from MI-LLC (Houston, Tex.).
[0000]
TABLE 9
Formulation of Sample 4
Additives
Concentration
Water
246.50
ppb
Soda Ash
0.50
ppb
Sodium Chloride
61.63
ppb
ECF-1868
5.0
ppb
PTS-200
3.0
ppb
SafeScav HS
1.0
ppb
Calothin
0.15
ppb
Poroseal
10.50
ppb
Barite UF
218.72
ppb
[0059] To analyse the temperature stability of the Sample 4 formulation, a portion of the fluid was hot rolled for 16 hours at 420° F. The rheology of the sample was measured with Fann 35 rheometer at a temperature of 120° F. as tabulated in Table 10.
[0000]
TABLE 10
Rheology of Sample 4
Rheology @ 120° F.
Fresh Fluid
After 16 hours hot rolled at 420° F.
600
72
74
300
48
49
200
35
36
100
24
25
6
8
7
3
6
6
Example 2—Viscosity Difference Between Linear and Crosslinked and Branched Polymer
[0060] In this example, 2 wt. % of a co-polymer formed from an acrylamide monomer and a sulfonated anionic monomer was dispersed in 2 wt. % CaBr 2 salt solution and the viscosity was measured on a Brookfield viscometer. The results are shown in Table 18 below. In one sample the co-polymer was a linear co-polymer, while in the other sample the co-polymer was crosslinked and branched.
[0000]
TABLE 11
Viscosity Results
Polymer
1.5 rpm
6.0 rpm
30.0 rpm
60.0 rpm
Crosslinked and
3700 cps
1350 cps
480 cps
320 cps
Branched
Linear Polymer
Too low to
Too low to
78 cps
74 cps
measure
measure
[0061] Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims. | A method of electrically logging a section of a wellbore includes circulating a wellbore fluid within the wellbore, the wellbore fluid including a base fluid; and a crosslinked and branched polymeric fluid loss control agent formed from at least an acrylamide monomer and a sulfonated anionic monomer; wherein the fluid loss control agent has an extent of crosslinking that is selected so that the fluid loss control agent has a viscosity that is within a peak viscosity response of the viscosity response curve; placing within the wellbore a wellbore logging tool capable of applying an electrical current to the wellbore; applying electrical current from the logging tool; and collecting an electrical log of the portion of the wellbore that has had electrical current applied thereto. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a windshield for motorcycles which is adjustably mounted by a holding means on the motorcycle and can be adjusted by a drive means into different positions.
The invention furthermore relates to a windshield for motorcycles which is adjustably mounted by a holding means on the motorcycle, the holding means having two non-parallel guides for setting different vertical and/or inclined positions of the windshield as it moves along the guides.
Finally, the invention relates to a drive means for an adjustably supported motor vehicle component, especially a windshield for motorcycles.
2. Description of Related Art
German Patent DE 39 41 875 C1 discloses a windshield which is mounted on a motorcycle so as to be adjustable in its height and its angular orientation by an adjustment means. The adjustment means contains at least two guide rails arranged at different angles and on each of which a respective sliding piece is movably supported. The windshield is connected to the two sliding pieces to be able to pivot around the transverse axis of the vehicle. An electric motor is located in the area of the front, lower guide rail and via a threaded rod transfers linear drive motion to the sliding piece which is supported on the front guide rail. The driving of the sliding piece via the threaded rod or a comparable dimensionally stable drive element limits the possible locations of the electric motor in the vicinity of the front guide rail.
SUMMARY OF THE INVENTION
A primary object of the present invention is to provide a windshield of the initially mentioned type with a drive device which is improved with respect to its arrangement and functionality.
Another object of the invention is to provide a windshield of the initially mentioned type with a holding means with two guides which is adjustably supported by a durable holding means with a simple structure.
A further object of the invention is to provide a drive means of simple structure for an adjustable vehicle component.
The initially mentioned object is achieved in accordance with the invention in that the drive means for the windshield has a cable line connection between the drive motor of the drive means and the adjustable windshield. A cable line connection which is formed, for example, in the manner of a Bowden cable, can be installed flexibly with bends or curvatures so that the drive means can be attached in the vicinity of the windshield or also farther away from it on the motorcycle without major structural limitations which entail rigid connecting elements, such as spindles or the like.
The initially mentioned object is also achieved in the initially mentioned windshield in accordance with the invention in that the drive means for the windshield has a lever means with at least one pivotally mounted drive lever between the drive motor of the drive means and the adjustable windshield. Rigid coupling by means of a pivotable drive lever enables reliable, play-free actuation and adjustment of the windshield. The lever ratios on the drive lever can be designed such that none of the drive movements applied to the drive lever are stepped up into large driven motions of the drive lever. This yields a compact execution of the drive unit.
If the drive means for the windshield has a lever means with two symmetrically arranged drive levers which are each connected on the outside end to a carriage, which is supported in the middle for pivoting in opposite directions, and which on the inner end are connected to one another by means of a movable coupling part, a uniform drive motion can be applied to two movable bearing parts of the windshield which are spaced apart from one another.
The second object is achieved by the first guide is mounted on the vehicle and the second guide being located on the windshield and by a driven carriage which is connected to the windshield on the first guide which is mounted on the vehicle and a vehicle-mounted part on the second guide located on the windshield being drive-engaged. Thus, both the vehicle-mounted part and also the windshield or the part connected to the windshield assume a guide function. Functionally, the carriage is connected via a cable line connection to the drive means. Here, the aforementioned advantages of the flexible arrangement of the drive means apply. A cable line connection is defined as any connections which are resistant to extension and compression, but which are flexible, and which can be flexible installed on the motorcycle, for example, in the manner of a Bowden cable.
Preferably, the windshield is mounted on the windshield bearing part which contains the second guide and which is connected to the carriage. In this configuration, the windshield bearing part forms a unit of the holding means and the windshield is interchangeably attached to the windshield bearing part and the holding means without effort.
If each cable line is guided to a respective one of a right-side and a left-side windshield bearing part or on two spaced mounting points on the windshield itself by the drive means, reliable adjustment of the windshield is ensured by this double driving.
Functionally, the drive means contains a rope pulley on which the cable or the rope of at least one cable or rope line can be wound and unwound. This pulley can have two adjacent peripheral grooves on which two cable lines can be wound and unwound at the same time and in the same direction so that the two cables, and thus the two windshield bearing parts, are synchronously activated. By means of one of the two cable line connections, at least one other movable part of the motorcycle can be adjusted synchronously to the motion of the windshield.
In one preferred embodiment, the guides are made as links in which stationary bearing elements, such as pins or the like, are guide-engaged. If the guides or links are formed to be linear, depending on the mutual assignment, a uniform adjustment motion is enabled. When the guides or links have at least one curved section, a pivoting motion of the windshield can be superimposed on the linear adjustment motion. Instead of the curved section, any shape of the guide or the link deviating from the linear section can make provide a pivoting motion of the windshield which deviates from the straight adjustment motion.
Preferably, the first guide or link is made in at least one longitudinal part of the holding means. This longitudinal part can be a central part of the holding means. Alternatively, there are two longitudinal parts in the right-side and left-side arrangement for the two windshield bearing parts.
Preferably, the longitudinal part is formed from at least two combined components which can be divided along the guide. This configuration facilitates the production of guides and the installation of the assigned components of the holding means, such as, for example, the carriage.
In the drive means for an adjustably supported vehicle component, especially a windshield for motorcycles, it is provided in accordance with the invention that the drive means has a cable line connection between the drive motor of the drive means and the vehicle component and a rope pulley on which at least one cable line can be wound and unwound and is guided by the drive means to the vehicle component or to a right-side and to a left-side vehicle component bearing part.
Furthermore, it is provided that the drive means has a lever means with at least one pivotally supported drive lever between the drive motor of the drive means and the adjustable vehicle component.
Further details of the configuration and advantages of the invention will become apparent from the following description taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view the front part of a motorcycle with an adjustable windshield;
FIG. 2 is a perspective view of the holding means of the windshield with a drive device in the initial position;
FIG. 3 is a view similar to that of FIG. 2 showing the drive device with the covering removed;
FIG. 4 is a view similar to that of FIGS. 2 & 3 showing the holding and drive device in the end position;
FIG. 5 is a perspective view of an inner side of the left-side part of the holding means;
FIG. 6 is a top view of the left-side part of the holding means and the drive device;
FIG. 7 shows in an inside view as shown in FIG. 5 , but with the holding means in the end position as shown in FIG. 4 ;
FIG. 8 is a perspective view from above of a second embodiment of a holding means of the windshield with a modified drive device in the initial position;
FIG. 9 is a view corresponding to that of FIG. 8 , but with the holding and drive device in the intermediate position;
FIG. 10 is a view corresponding to that of FIG. 8 , but with the holding and drive device in the end position;
FIG. 11 is a plan view of the holding means of the second embodiment in the initial position according to FIG. 8 ;
FIG. 12 is a plan view of the holding means in the intermediate position according to FIG. 9 ; and
FIG. 13 is a plan view of the holding means in the end position according to FIG. 10 .
DETAILED DESCRIPTION OF THE INVENTION
The partially depicted motorcycle 1 of FIG. 1 has a cowling 2 and a windshield 3 which is mounted above the cowling 2 by a holding means 4 such that it can route the slipstream past the motorcycle driver 5 . If necessary, the windshield 3 can be adjusted in its height and/or its angle of inclination by the holding means 4 out of a most vertical set position (shown schematically in FIG. 1 in broken lines) into a highly inclined position (shown in solid lines).
The holding means 4 contains a holding frame 6 (only the part of the left part of which is shown in FIGS. 2 to 7 ) with mounting or screw openings 7 (see, FIGS. 5 & 8 ) for fixing the holding frame 6 on the frame of the motorcycle 1 or on the cowling 2 . A drive means 8 is mounted on the central transverse part 9 of the holding frame 6 . On the longitudinal side parts 10 (only the left longitudinal part 10 being shown), a linear link guide 11 (see, FIG. 4 ) with a, for example, rectangle cross section is formed in which an elongated carriage 12 is movably held. A front bearing pin 13 extends through a side oblong hole opening 14 of the link guide 11 into the bearing hole 15 of a windshield bearing part 16 . The carriage 12 is drive-engaged with a part, e.g., a stationary rear bearing pin 18 that projects on the back end 17 of the longitudinal part 10 , laterally to the outside, and fits into the link guide 19 of the windshield bearing part 16 which is formed as an oblong hole. The guides 11 , 19 are non-parallel with respect to each other, as is apparent from the drawings, for varying the position of the windshield 3 in terms of height and/or inclination, when it is moved along the guides. The rear bearing pin 18 is located above the link guide 11 , and the link guide 19 of the windshield bearing part 16 runs underneath the front bearing pin so that the windshield bearing part 16 is swung up around the bearing pin 13 if it is pushed lengthwise by means of the driven carriage 12 and the bearing pin 13 . The windshield bearing part 16 has mounting openings 20 for attaching the windshield 3 .
Next to the link guide 11 and parallel to it, a channel 21 is formed, which connects with the opening 14 of the link guide 11 (see FIGS. 5 to 7 ) and in which a drive cable 22 , which is connected to the carriage 12 , is movably held. The drive cable 22 is movably guided in jacketing 23 from the windshield bearing part 16 , via a bend 24 , to the pulley 25 of the central drive means 8 . The pulley 25 is mounted on the gear shaft of the force transmission mechanism 27 driven by the electric motor 26 (see especially FIG. 3 ), and has a peripheral groove 28 in which the drive cable 22 can be wound and unwound and which is resistant to tension and compression. By means of retaining pin 29 which is mounted on the end of the drive cable 22 and which is inserted in a recess of the rope pulley 25 , the drive cable 22 is attached to the pulley 25 in the peripheral direction, resistant to extension. The pulley 25 has a second peripheral groove 30 next to the first peripheral groove 28 in which, in the same direction of rotation, a second drive cable 31 for the opposing, right-side windshield bearing part (not shown) is located. The covering 32 (see FIG. 2 ) covers and seals the pulley 25 .
When the electric motor 26 is actuated, for example, via a hand switch on the handlebars or via a speed-dependent or slipstream-dependent control, the drives cables 22 , 31 are taken up at the same time from the position shown in FIG. 1 in which the two windshield bearing parts 16 are located in the front position and hold the windshield 3 in the lower vertical position with a slight upward inclination, via rotation of the cable pulley 25 so that, via rearward displacement of the respective carriage 12 , the windshield bearing parts 16 , and thus the windshield 3 , are raised and inclined more dramatically against the slipstream. The end position is shown in FIGS. 4 & 7 .
The opposing drive motion of the electric motor 26 moves the windshield 3 back again into the reclined position or into an intermediate position.
If the link guide 11 is positioned so that it rises over its length relative to the lengthwise axis of the motorcycle, the front bearing pin 13 , and thus the windshield bearing part 16 and the windshield 3 , are additionally raised in its vertical position.
One or both link guides 11 , 19 can have angled or curved sections so that a certain swinging behavior of the windshield 3 which is dependent on the lengthwise displacement can be fixed.
The largely flexibly installable drive cables 22 , 31 of the drive means 8 enable a comparatively free arrangement of the drive means 8 relative to the movable holding means 4 or to the windshield 3 so that the electric motor 26 with the transmission 27 and the pulley 25 can also be located away from the holding means 4 and at angular positions to it, which is something which could be accomplished by a conventional mechanical coupling only with high construction cost.
The pulley 25 can guide two synchronously drivable drive cables to two separate windshield bearing parts 16 which are spaced apart, and different distances from the pulley 25 to each of the windshield bearing parts 16 can be easily bridged.
In another embodiment of the windshield (see, FIGS. 8 to 13 ), with a modified drive means, the holding means 4 contains a drive pulley 33 (see FIG. 11 ) which is located on the central transverse part 9 in the middle between the two side longitudinal parts 10 (only the left longitudinal part 10 is shown) and is pivotally supported on it and is coupled to rotate with the electric motor 26 via the transmission mechanism 27 . The drive wheel 33 is covered by a cover 34 which is mounted on the transverse part 9 . The carriage 12 of the windshield bearing part 16 is U-shaped and sits movably on the guide 11 which is formed sa a rail. On the two brackets 35 , which project inward from the carriage 12 , a pin 36 is mounted on which a left drive lever 37 is pivotally supported. The drive lever 37 extends roughly to the middle of the transverse part 9 , resting directly on the cover 34 , and supported to move and pivot on a pin 38 which projects upward, for example, from the cover 34 and which is held to be able to move into an elongated hole 39 in the drive lever 37 .
A right drive lever 40 for driving the right windshield bearing part or its carriage is located symmetrically to the left drive lever 37 and is supported in the corresponding manner by means of a pin 42 which fits into the longitudinal slot 41 . The right drive lever 40 has an inner end 43 which is bent up such that this end 43 rests on the inner end 44 of the left drive lever 37 . The inner ends 43 , 44 of two drive levers 37 , 40 , each contain a longitudinal guide slot 45 , 46 in which is held a movable coupling part, e.g., the guide pin 47 which is mounted on a sliding piece 48 which is movably supported in a longitudinal guide 49 on the cover 34 . A drive part, e.g., a guide pin 50 which is eccentrically mounted on the drive wheel 33 extends through an arc-shaped slot 51 in the cover 34 (which defines a circular path) up into the longitudinal guide slot 45 in the drive lever 37 (as shown) or into the lengthwise hole 46 of the right drive lever 40 .
To change the position of the windshield 3 , the drive means 8 causes the drive wheel 33 to rotate and swings the windshield 3 , for example, by an angle of a maximum roughly 130° clockwise as shown in FIGS. 8 to 13 . In doing so, the pin 50 , which slides in the longitudinal guide slot 45 , pivots the left drive lever 37 around the pin 38 so that the drive lever 37 moves the carriage 12 , and thus, the left windshield bearing part 16 to the rear via the middle intermediate position shown in FIGS. 9 & 12 into the end position which is shown in FIGS. 10 & 13 and in which the windshield 3 is raised to have a greater inclination.
As a result of the pin 50 which couples the two drive levers 37 , 40 to one another, the drive motion is transferred to the two drive levers 37 , 40 for their synchronous movement.
This embodiment has a small installation depth of the drive, since the drive motion takes place via the drive lever which pivots through only a comparatively small angle. The rotary motion of the pin 50 in the vicinity of the two end positions causes only minor pivoting of the two drive levers 37 , 40 , so that starting and braking take place gently in the vicinity of the two end positions.
The drive means 8 is controlled via Hall sensors in the drive motor and/or via microswitches which are triggered via the drive wheel 33 . There can also be a comparable control in the first embodiment. | A windshield for motorbikes which can be variably positioned at various angles of inclination on the motorbike by a holding device ( 6 ) and a drive device ( 8 ). The drive device ( 8 ) has a cable or a cable pull connection ( 22, 23, 24, 25 ) between a drive motor ( 26 ) of the drive device ( 8 ) and a support element ( 16 ) for the adjustable windshield. The holding device ( 6 ) can also be formed by two non-parallel guides ( 11, 19 ) for varying the position of the windshield ( 3 ) in terms of height and/or inclination, when it is moved along the guides ( 13, 19 ). The first guide ( 11 ) is fixed to the vehicle and the second guiding mechanism ( 19 ) is arranged on the windshield ( 3 ). A driveable carriage ( 12 ) which is connected to a support element ( 16 ) for the adjustable windshield and is situated on the first guide ( 11 ) engages a part ( 18 ) which is fixed to the vehicle and is situated on the second guide ( 19 ). | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a tipper mechanism to reposition a container, and more particularly, to such tipping mechanism having a plurality of actuating devices sequenced to overturn the container.
2. Description of the Prior Art
In manufacturing or assembly processes, containers may be moved through a variety of steps. These steps may involve filling the container with product as well as sealing and labeling the container. At the conclusion of the manufacturing or assembly process the containers may be discharged while other containers are moved through the same processing steps. Once the containers are discharged, they are typically moved to a storage location or warehouse to await shipment to customers.
It may be desirable to reposition the containers during the manufacturing or assembly process. For example, the step of sealing the container may require that the container first be overturned. It also may be desirable to reposition the container before transport to a warehouse for storage in order to facilitate storage of the container. For example, asymmetrically designed containers may require less storage space when in an inverted position. Repositioning the containers prior to transport to a warehouse may reduce the amount of handling necessary to store the containers in an inverted position.
Containers may be manually repositioned. This approach however has disadvantages. Repetitive stress injuries may result from the continuing motions required to reposition containers on manufacturing or assembly lines. Unfortunately, if a repetitive stress injury does occur, the manufacturing line throughput rate may suffer while the injury is attended to. This may result in additional business related costs due to lost manufacturing throughput and medical expenses.
Often times it is desirable to move containers through the assembly process at high throughput rates. The desired throughput rates may not be easily accommodated by human interaction however. For example, manual repositioning would be difficult if the containers were heavy or large in size. Unfortunately, the assembly process throughput rate must be reduced under these circumstances to levels appropriate for human interaction.
Various attempts have been made in the prior art to overturn containers. In one prior art machine, a container is received by a first conveyor belt and is moved up an inclined portion. Once the container reaches the end of the inclined portion, the container may tumble and land on an opposite end onto a second conveyor belt. The end of the inclined portion is optimally positioned at a height large enough to allow the container's forward momentum to cause the container to tumble and land on the opposite end on the second conveyor belt. This approach unfortunately has the disadvantage of potentially damaging the container. The container may be made of destructible materials such as cardboard. In addition, the containers must be dropped from heights sufficient to provide for overturning.
In another prior art machine, the container is positioned on a conveyor belt to be received by mechanical gripping arms. These mechanical gripping arms may grip the container, then rotate the container by 180° by tipping the container end-over-end. The mechanical gripping arms may then release the container back onto the conveyor belt. This approach unfortunately requires a difficult mechanical design to grip the containers without damage.
SUMMARY OF THE INVENTION
The present invention overcomes the disadvantages found in the prior art by providing a transfer machine tipping mechanism for overturning a container being moved from a first station to a second station. The transfer machine tipper mechanism has a plurality of actuators to engage and rotate the container. The actuators are sequenced to rotate the container from an initial orientation to a final orientation wherein the final orientation is defined by the top and bottom of the container being inverted from the initial orientation.
In a preferred embodiment, the transfer machine tipper mechanism is provided in the environment of a workpiece approaching mechanism. The workpiece approaching mechanism includes a conveyor assembly and a tipper mechanism. The conveyor assembly comprises a conveyor belt, a conveyor roller and a conveyor end roller. The conveyor belt is rotatably supported by the conveyor roller and the conveyor end roller to move a container through the tipper mechanism. The container may be a bucket which is generally cylindrical in shape, which has a top and a bottom. The bottom is frictionally supported by the conveyor belt. The conveyor roller and the conveyor end roller are thus rotatably attached to the conveyor frame.
In the preferred embodiment, the tipper mechanism is comprised of four actuators. Each actuator has a pneumatic cylinder, a cylinder rod and a cylinder housing, where the pneumatic cylinder is securely attached to the cylinder housing, and the cylinder housing is attached to the conveyor frame. The second and third actuators have a tip attached at a distal end of the respective cylinder rods to provide a non-damaging means of engagement to the container. The tip may be constructed of any material including plastic. The first and fourth actuators each have a stop attached to a distal end of the respective cylinder rod to provide a means of engagement to the container. The tipper mechanism further includes an electric eye which is mounted in the conveyor frame to detect passage of the container to initiate sequencing of the four actuators to tip the container.
In the preferred embodiment, when the container reaches a first position, the electric eye has sensed the passage of the container on the conveyor belt and initiates the sequencing of the four actuators. The first actuator extends to a first position and the fourth actuator extends to a first position. Once the stop of the first actuator extends to the first position, the container may not continue movement in the forward direction on the conveyor belt. The actuators are positioned on the conveyor frame, such that a distance d1 between an axis of the first actuator and an axis of the second actuator is optimal when slightly less than the diameter of the bottom of the container. Thus, when the container contacts the stop of the first actuator when the stop is in the first position, the tip of the second actuator may optimally contact the bottom of the container to begin rotation of the container. The distance d2 is the distance between the axis of the first actuator and the axis of the third actuator. The container has a center of gravity between its respective top and bottom. Thus, the stop of the first actuator being in the first position provides a mechanical moment, such that the container may be rotated about the stop. The container has a bottom center which is a perpendicular intersection of the center of gravity of the container with the bottom end of the container. Thus, distance d2 is optimal when slightly larger than the radius of the bottom of the container so that the bottom center is between the axis of the first actuator and the axis of the third actuator. This ensures the rotation of the container about the stop of the first actuator when the stop of the first actuator is in the first position.
In the preferred embodiment, once the first actuator blocks the base of the container from moving in the forward direction, the top of the container may be rotated in the forward direction over the base of the container. The first actuator engages the container at a first contact point at a forward side of the container to block the bottom of the container from moving in the forward direction. The first actuator extends the stop to the first position to block the bottom of the container.
In the preferred embodiment, the second actuator rotates the container to a first position. The second actuator engages the bottom of the container to lift the container at a second contact point to a first height where the container is rotated about the first contact point. The second contact point is located on the bottom of the container between the bottom center of the container and an edge of the bottom closest to the first station. The second actuator engages the bottom of the container with the tip to avoid damaging the container.
In the preferred embodiment, the third actuator rotates the container from a first position to a second position where the second position is midway between the initial orientation and the final orientation. The third actuator engages the bottom of the container to lift the container at a third contact point from the first height to a second height, where the container is rotated about the first contact point. The third contact point is located on the bottom of the container between the bottom center of the container and the second contact point. The third actuator extends the tip to a first position and provides sufficient momentum to rotate the container about the first contact point so that the center of gravity of the container is closer to the second station than the first contact point.
In the preferred embodiment, the fourth actuator blocks the top of the container from moving in the forward direction so that the first actuator may rotate the bottom of the container over the top of the container until the container is in the final orientation. The fourth actuator engages the container at a fourth contact point on the top of the container when the center of gravity of the container is closer to the second station than the first contact point in order to block the top of the container from moving in the forward direction. The fourth actuator is extended to a first position such that the center of gravity of the container being above the fourth contact point produces a mechanical moment about the fourth contact point. In the preferred embodiment, the first actuator extending from the first position to a second position when the center of gravity of the container is closer to the second station than the first contact point provides momentum to the container sufficient to complete rotation of the container about the fourth contact point to the final orientation.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:
FIG. 1 is a side elevational view of the invention and workpiece approaching mechanism;
FIG. 2 is a front elevational view;
FIG. 3 is a top plan view thereof showing workpiece in phantom dashed line and slightly advanced from position of FIG. 1 and FIG. 2;
FIG. 4 is a view similar to that of FIG. 1 with workpiece advanced to mechanical stop;
FIG. 5 is a view similar to that of FIG. 4 with workpiece advanced to rotate against stop due to initiation of mechanism and shown to continue to rotate shown in phantom dashed line;
FIG. 6 is a view similar to that of FIG. 5 with workpiece advanced to rotate due to further action of mechanism and momentum of workpiece shown in phantom dashed line;
FIG. 7 is a view similar to that of FIG. 6 with workpiece advanced to continue to rotate due to yet further action of mechanism shown in phantom dashed line; and
FIG. 8 is a view similar to that of FIG. 7 with workpiece advanced to completely tip over and assume inverse position due to final action of mechanism and showing workpiece advancing to discharge position shown in phantom dashed line.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, where like reference numerals refer to like elements throughout the several views, FIG. 1 is a side elevational view of the invention and workpiece approaching mechanism. The workpiece approaching mechanism is shown generally at 10, and includes a conveyor assembly 12 and a tipper mechanism 15. Conveyor assembly 12 comprises conveyor belt 14, conveyor roller 16, and conveyor end roller 18. Conveyor belt 14 is rotatably supported by conveyor roller 16, conveyor end roller 18, and one or more other conveyor rollers not shown. Conveyor roller 16 and conveyor end roller 18 are rotatably attached to conveyor frame 28. Conveyor belt 14 supports container 22 at surface 17 to move container 22 in the direction shown by arrow 20. Conveyor belt 14 moves container 22 from a first station 6 located before conveyor roller 16, through tipper mechanism 15 then on to a second station 8 located at or beyond conveyor end roller 18. Tipper mechanism 15 is located between the first station 6 and the second station 8. Container 22 has forward side 23 which is the side of container 22 which is closest to the second station 8, and a rear side 25 which is closest to the first station 6. Container 22 is a bucket which is generally cylindrical in shape, which has a top 24 and a bottom 26. Bottom 26 is frictionally supported by conveyor belt 14. Tipper mechanism 15 is comprised of actuator 30, actuator 32, actuator 34 and actuator 36. Tipper mechanism 15 rotates container 22 from an initial orientation to a final orientation, where the final orientation is defined by the top and bottom of the container being inverted from the initial orientation. Actuator 30 is comprised of pneumatic cylinder 38, cylinder rod 40, tip 42, and cylinder housing 44. Pneumatic cylinder 38 is securely attached to cylinder housing 44. Cylinder housing 44 in turn is securely held by conveyor frame 28. Tip 42 is attached at a distal end 46 of cylinder rod 40. Tip 42 provides a non-damaging means of engagement to container 22. Actuator 32 is comprised of pneumatic cylinder 48, cylinder rod 50, tip 52, and cylinder housing 54. Pneumatic cylinder 48 is securely attached to cylinder housing 54. Cylinder housing 54 in turn is securely held by conveyor frame 28. Tip 52 is attached at a distal end 56 of cylinder rod 50. Tip 52 provides a non-damaging means of engagement to container 22. Actuator 34 is comprised of pneumatic cylinder 58, pneumatic cylinder 60, cylinder rod 62, stop 64, and cylinder housing 66. Pneumatic cylinders 38 and 40 are securely attached to cylinder housing 66. Cylinder housing 66 in turn is securely held by conveyor frame 28. Stop 64 is attached at a distal end 68 of cylinder rod 40. Stop 64 provides a means of engagement to container 22. Actuator 36 is comprised of pneumatic cylinder 70, cylinder rod 72, stop 74, and cylinder housing 76. Pneumatic cylinder 70 is securely attached to cylinder housing 76. Cylinder housing 76 in turn is securely held by conveyor frame 28. Stop 74 is attached at a distal end 78 of cylinder rod 72. Stop 74 provides a means of engagement to container 22.
Actuators 30, 32, 34 and 36 are controlled by pneumatic means which are not shown. Electric eye 80 is mounted in conveyor frame 28 to detect passage of container 22 in the direction of arrow 20 on conveyor belt 14 to initiate sequencing of actuators 30, 32, 34 and 36. Container 22 is shown at position 82. Position 82 is prior to engagement of actuators 30, 32, 34 or 36 by container 22.
FIG. 2 is a front elevational view showing container 22 in position 82. Container 22 is shown being supported by ribs 84 of conveyor belt 14. FIG. 2 shows pneumatic cylinder 70 of actuator 36 supported by cylinder housing 76. Cylinder housing 76 is firmly attached to conveyor frame 28 via bolt 86 and bolt 88. In a likewise fashion, cylinder housing 66 is firmly attached to conveyor frame 28 via bolt 90 and bolt 92 (see, FIG. 3). Cylinder housing 54 is firmly attached to conveyor frame 28 via bolt 94 and bolt 96 (see, FIG. 3). Cylinder housing 44 is firmly attached to conveyor frame 28 via bolt 98 and bolt 100 (see, FIG. 3). FIG. 2 further shows pneumatic cylinder 60 being supported by and attached to cylinder housing 66 at proximal end 102. Pneumatic cylinder 60 is supported at proximal end 102 so pneumatic cylinder 58 and pneumatic cylinder 60 may be coupled together for a two-stage operation.
FIG. 3 is a top plan view showing the workpiece and a phantom dashed line in a position slightly advanced from the position of FIGS. 1 and 2. The workpiece shown in FIG. 3 is container 22. Container 22 is shown in position 104. FIG. 3 shows belts 84 of conveyor belt 14 supported by conveyor end roller 18 and conveyor roller 16. Conveyor belt 14 is further comprised of belts 106 which are rotatably supported by conveyor roller 16 and at least one other conveyor roller not shown. FIG. 3 shows tip 42 supported by and extending up through cylinder housing 44, tip 52 supported by and extending up through cylinder housing 54, stop 64 supported by and extending up through cylinder housing 66, and stop 74 supported by and extending up through cylinder housing 76. As container 22 moves in the direction of arrow 20 from position 82 to position 104, electric eye 80 is tripped, indicating the start of sequencing of actuators 30, 32, 34 and 36. Once in position 104, stop 64 has extended to a first position 108, and stop 74 has extended to a first position 110 (see also, FIG. 4). As conveyor belt 14 is further advanced in the direction of arrow 20, container 22 continues to move from position 104 to position 106.
FIG. 4 is a view similar to that of FIG. 1 with container 22 advanced to position 112. Once container 22 reaches position 104, electric eye 80 has sensed the passage of container 22 on conveyor belt 14 and begins the sequencing of actuators 30, 32, 34 and 36. Actuator 34 extends to a first position 108, and actuator 36 extends to a first position 110. The extension of stop 64 to first position 108 is caused by activation of pneumatic cylinder 60. The extension of stop 74 to first position 110 is caused by activation of pneumatic cylinder 70. Tip 42 and cylinder rod 40 have a common axis 114. Tip 52 and cylinder rod 50 have a common axis 116. Stop 64 and cylinder rod 62 have a common axis 118. Actuators 30, 32 and 34 are optimally positioned on conveyor frame 28. Distance d1 between axis 114 of actuator 30 and axis 118 of actuator 34 is optimal when slightly less than the diameter of bottom 26. Thus, when container 22 contacts stop 64 when stop 64 is in first position 108, tip 42 may optimally contact bottom 26 of container 22 when actuator 30 is activated to begin rotation of container 22. Distance d2 is between axis 116 of actuator 32 and axis 118 of actuator 34. Container 22 has a center of gravity between top 24 and bottom 26. Stop 64 being in first position 108 provides a mechanical moment between the center of gravity and a first contact point 65 so that container 22 may be rotated over stop 64. First contact point 65 is the point of contact of stop 64 with the surface of container 22 at forward side 23. Once stop 64 extends to first position 108 and contacts the surface of the container at first contact point 65, bottom 26 of container 22 may not continue movement in the direction of arrow 20 to allow top 24 of container 22 to be rotated over bottom 26 in the forward direction of arrow 20. Container 22 further has a bottom center 27 which is the perpendicular intersection of the center of gravity of container 22 with end 26. Distance d2 is optimal when slightly larger than the radius of bottom 26 of container 22 so that the bottom center 27 is between axis 116 and axis 118. This insures rotation of container 22 about stop 64 when stop 64 is in first position 108 (see also, FIG. 5).
FIG. 5 is a view similar to that of FIG. 4 with container 22 advanced to rotate against stop 64. FIG. 5 shows container 22 in position 120 with subsequent rotation to position 122 over first contact point 65. Actuator 30 is activated and lifts tip 42 to a first position 124. Tip 42 contacts bottom 26 of container 22 at second contact point 125. The extension of tip 42 to first position 124 while contacting bottom 26 rotates container 22 to position 120 from position 112 over first contact point 65. This extension of tip 42 to first position 124 lifts the bottom of container 22 to a first height 127. First height 127 is the distance between bottom 26 of container 22 which is closest to rear side 25 of container 22 and the surface 17 of the conveyor belt 14 when tip 42 is in position 124. Tip 42 being extended to first position 124 in the direction of arrow 126 results in rotation of container 22 in the direction shown by arrow 128. Once tip 42 reaches first position 124, tip 52 extends to a first position 130 in the direction of arrow 132 to rotate container 22 from position 120 to position 122 about first contact point 65 in the direction shown by arrow 134. Movement of container 22 from position 120 to position 122 is accomplished by moving tip 52 in the direction of arrow 132. Tip 52 contacts bottom 26 of container 22 at third contact point 53. Third contact point 53 is located on bottom 26 of container 22 between bottom center 27 of container 22 and second contact point 125. This extension of tip 52 to first position 130 lifts the bottom of container 22 from the first height 127 to a second height 129. Second height 129 is distance between bottom 26 of container 22 which is closest to rear side 25 of container 22 and the surface 17 of the conveyor belt 14 when tip 52 is in first position 130. The rotation of container 22 from position 120 to position 122 provides sufficient momentum to enable the center of gravity of the container to pass beyond stop 64 in the direction of arrow 20 and to a position closer to second station 8 than stop 64.
FIG. 6 is a view similar to that of FIG. 5 with container 22 advanced to rotate from position 122 to position 140. Tip 42 of actuator 30 is in first position 124. Tip 52 of actuator 32 is fully extended to first position 130. In comparison to FIG. 5, the momentum of container 22 from traveling in the direction of arrow 20 once tip 52 is fully extended to first position 130 in the direction of arrow 132, results in container 22 rotating in the direction shown by arrows 142 and 144, while continuing the forward motion shown by arrow 20 to rotate in the direction of arrow 146 to position 140. Thus, it is understood that the tipping and tumbling being exhibited by movement in the direction shown by arrows 142, 144 and 146 results from a combination of a forward momentum of container 22 in the direction of arrow 20, and the extension of tip 42 to first position 124 in the direction of arrow 126, and the extension of tip 52 to first position 130 in the direction of arrow 132. Thus, the size and weight of container 22 determines the required speed of travel of container 22 in the direction of arrow 20, as well as the distance of extension of tip 42 to first position 124 and tip 52 to first position 130, necessary to overturn container 22.
FIG. 7 is a view similar to that of FIG. 6 with container 22 advanced to continue to rotate to position 170. Tip 42 of actuator 30 is in position 124, and tip 52 of actuator 32 is in position 130. Stop 74 of actuator 36 is in position 110. Stop 64 of actuator 34 extends from first position 108 to second position 172. Pneumatic cylinder 58 moves stop 64 in the direction of arrow 174 to position 172. Stop 64 extending from position 108 to position 172 causes container 22 to continue to rotate in the direction of arrows 176 and 178. Stop 74, currently in position 110, begins retracting in the direction of arrow 180 to allow top 24 of container 22 to be supported by conveyor belt 14. Stop 74 contacts container 22 at fourth contact point 75 on top 24 when the center of gravity of container 22 is closer to second station 8 than first contact point 65 to block top 24 of container 22 at fourth contact point 75 from moving in the forward direction in the direction of arrow 20. The center of gravity of container 22 being above fourth contact point 75 produces a mechanical moment about fourth contact point 75 so that when stop 64 of actuator 34 extends from first position 108 to second position 172, stop 64 provides a momentum to container 22 sufficient to complete rotation of container 22 about fourth contact point 75 to the final orientation.
FIG. 8 is a view similar to that of FIG. 7 with container 22 rotated to be completely tipped over. FIG. 8 shows container 22 in position 190 after further rotation in the direction of arrows 192 and 194. Rotation of container 22 in the direction of arrows 192 and 194 was initiated by stop 64 extending from first position 108 to second position 172, in addition to the momentum of container 22 in the direction of arrow 20. Container 22 falls to position 196 so that top 24 is supported on conveyor belt 14. Position 196 is the final orientation of container 22. Position 112 is the initial orientation of container 22. In the final orientation, top 24 and bottom 26 of container 22 are inverted from the initial orientation in a direction parallel with axis 114, 116 or 118. Tip 42 is then retracted in the direction of arrow 198 to a fully retracted position. Tip 52 is retracted in the direction of arrow 200 to a fully retracted position. Stop 64 is retracted in the direction of arrows 202 and 204 to a fully retracted position. Stop 74 is shown in the fully retracted position having been retracted in the direction of arrow 180 (see also, FIG. 7). Once container 22 is in position 196, conveyor belt 14 may carry container 22 to the next step in the process or to a final storage area.
Having thus described the preferred embodiments of the present invention, those of skill in the art will readily appreciate that the teachings found herein may be applied to yet other embodiments within the scope of the claims hereto attached. | A transfer machine tipper mechanism for overturning a container being moved from a first station to a second station. The transfer machine tipper mechanism has a plurality of actuators to engage and rotate the container. The actuators are sequenced to rotate the container from an initial orientation to a final orientation wherein the final orientation is defined by the top and bottom of the container being inverted from the initial orientation. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to a compressor system. More particularly, the present invention relates to an air/oil separator tank for use with an air compressor.
BACKGROUND OF THE INVENTION
[0002] In conventional air compressor systems air is compressed in a compression chamber or airend of a compressor, for example, by a set of rotary screws, and a lubricant, such as oil, is injected into the compression chamber and mixes with the compressed air. The oil is generally injected into the compression chamber for a number of reasons including cooling the air compressor system, lubricating bearings, balancing axial forces and sealing the rotary screws. Although using oil is essential for operating these types of air compressor systems, the oil must be removed from the stream of compressed air before the compressed air may be used downstream for pneumatic equipment and/or other tools.
[0003] In such conventional air compressor systems, the compressed air and oil mixture discharged from the airend of the compressor flows with a high velocity into a separator tank where the air and oil of the air/oil mixture are caused to separate. The separator tank is usually cylindrical and the air/oil mixture is directed around an inner wall of a separation chamber. The combination of the centrifugal forces acting on the air/oil mixture and contact between the air/oil mixture and the inner wall of the separation chamber causes much of the oil to separate from the air/oil mixture, thereby allowing gravity to draw most of the oil downwardly into a lower portion of the separation chamber and also allowing the air to separate from the oil and flow upwardly into an upper portion of the separation chamber to achieve primary separation.
[0004] In these conventional air compressor systems, the compressed air, along with some fine oil droplets or mist entrained therein, passes through a separator element placed within the upper portion of the separation chamber, thereby coalescing most of the remaining oil in the air stream to achieve secondary separation before the compressed air is transferred out of the separator tank. The coalesced oil pools in a bottom portion of the separator element and is returned to the airend of the compressor by a scavenging line.
SUMMARY OF THE INVENTION
[0005] Conventional air compressor systems as described above typically include a lid mounted on the separator tank to hold the separator element within the separation chamber of the separator tank. The separator element must be held in place because there is an upward force on the separator element due to the pressure differential between the wet side (outer) and dry side (inner) portions of the separator element. Conventional air compressor systems include an air exit port in the lid, and typically, a minimum pressure check valve (MPCV) assembly is operatively connected to the air exit port in the lid. After passing through the MPCV assembly, the compressed air is typically sent to an aftercooler, and then the cooled compressed air may be conveyed to pneumatic equipment and/or other tools. As can be appreciated by those skilled in the art, it is generally necessary to service or replace separator elements from time-to-time. In the conventional air compressor systems described above, before a separator element can be serviced or replaced, the air discharge hose and MPCV assembly, which usually includes associated fittings, must be disconnected from the lid. This increases the time required to service or replace the separator element. Thus, there is a need for an air compressor system which eliminates the necessity of disconnecting the air discharge hose and MPCV assembly from the separator tank prior to servicing or replacing a separator element.
[0006] The conventional way to remove oil from inside a separator element of the air compressor systems described above is to pass an independent scavenge tube through the lid mounted on the tank and down into an open area of the separator element. The scavenge tube extends to the bottom of the separator element and draws off the excess oil to prevent saturation of the separating media of the separator element. Positioning the scavenge tube through the lid and down into the open area of the separator element can be problematic. If the scavenge tube is too long, it may puncture the bottom of the separator element. If the scavenge tube is too short, it may not be sufficiently effective in removing the oil. In addition, before the separator element is replaced, the scavenge tube must be removed from the separator tank lid. Thus, there is a need for a scavenging device which is easy to install, which does not adversely affect the servicing or replacing of a separator element, and which also effectively removes oil from the bottom of the separator element.
[0007] The present invention provides in one aspect thereof, a separator tank having an air exit port in a side wall of the tank, rather than in the lid of the tank as is the case with many known designs. Air from an air/oil mixture flows into an upper portion of a separation chamber of the tank, through a separator element positioned within the upper portion of the separation chamber, and out the air exit port in the side wall of the tank. An MPCV assembly is operatively connected to the air exit port in the side wall of the tank. Because the MPCV assembly and air discharge hose are not attached to the lid of the separator tank, in order to service or replace the separator element, the lid mounted on the separator tank is simply removed or pivoted out of the way to allow access to the separator element, without having to first disconnect the discharge hose and MPCV assembly.
[0008] The present invention provides in another aspect thereof, a separator element hold down mechanism between the separator element and the lid to position the separator element within the separation chamber and in spaced relation from the lid. Air separated from the air/oil mixture will flow through the separator element, towards the lid, and out the air exit port in the side wall of the separator tank.
[0009] The present invention provides in another aspect thereof, a separator element oil scavenge device which draws oil up off of the bottom of the separator element, and which transports the scavenged oil through the side wall of a separator tank. In one embodiment of the present invention, the scavenge device includes a tube which is integrally formed with the separator element. Once the tube is securely attached to the separator element and an end of the tube is located at a predetermined position relative to the bottom of the separator element, there is no need for independent adjustment of the tube relative to the bottom of the separator element and, as a consequence, no risk of making the tube too long or too short.
[0010] Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a perspective view of an air compressor system embodying the present invention.
[0012] [0012]FIG. 2 is a perspective view of a separator tank shown in FIG. 1.
[0013] [0013]FIG. 3 is a cross-sectional view of a separator tank assembly shown in FIG. 1.
[0014] [0014]FIG. 4 is a partial cross-sectional view of a portion of an alternative embodiment of a separator tank assembly of the present invention.
[0015] [0015]FIG. 5 is a partial cross-sectional view of a portion of an alternative embodiment of a separator tank assembly of the present invention.
[0016] [0016]FIG. 6 is a partial cross-sectional view of a portion of an alternative embodiment of a separator tank assembly of the present invention.
[0017] [0017]FIG. 7 is a perspective view of the separator element hold down mechanism of FIG. 6.
[0018] [0018]FIG. 8 is a partial cross-sectional view of a portion of an alternative embodiment of a separator tank assembly of the present invention.
[0019] [0019]FIG. 9 is a partial cross-sectional view of a portion of an alternative embodiment of a separator tank assembly of the present invention.
[0020] Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] Illustrated in FIG. 1 is an air compressor system 10 embodying the present invention. It should be understood that the present invention is capable of use in other compressor systems, and the air compressor system 10 is merely shown and described as an example of one such system.
[0022] The air compressor system 10 illustrated in FIG. 1 includes a compressor 14 , a motor 18 , and a separator tank 22 . Although the separator tank 22 as disclosed herein is used to separate oil from an air/oil mixture, it is contemplated that the separator tank 22 may be used to separate a volume of gas from any mixed media combination, including any gas/liquid combination. In addition, it is contemplated that the compressor 14 may be any suitable compressor, such as an oil-flooded air compressor. However, for the purposes of describing the preferred embodiment, the compressor 14 is a rotary screw compressor.
[0023] The separator tank 22 may be constructed of any number of suitable materials. However, in a preferred embodiment, the separator tank 22 is a cast separator tank. Air enters the compressor 14 and is compressed by rotary screws (not shown) found within the compressor 14 . Oil is injected into the compressor 14 to lubricate the rotary screws and a gearbox (not shown) which drives the rotary screws. The oil further serves as a sealing means for the compressor 14 . The compressed air and some of the oil travel out of the rotary screws through an airend discharge opening of the compressor and into an airend inlet opening 26 (FIG. 2) in the separator tank 22 . The separator tank 22 serves to separate oil from the compressed air and also serves as an oil sump for the oil used to lubricate the rotary screws, the gearbox and other components. The compressed air and oil enter the separator tank 22 and are caused to undergo a cyclonic motion within the separator tank 22 . As the compressed air and oil are flung around an inner surface of the separator tank 22 , the oil will slide down the inner surface of the separator tank 22 and collect in the bottom of the separator tank 22 , and the air will move up and out of the; separator tank 22 for further filtering, cooling and ultimate use.
[0024] Referring to FIG. 3, the separator tank 22 includes a side wall 30 and defines a separation chamber 34 having a lower portion 38 and an upper portion 42 . The lower portion 38 of the separation chamber 34 serves as an oil reservoir or sump for the oil that is separated from the air/oil mixture introduced into the separation chamber 34 via channel 46 (see also FIG. 2) during the primary separation process. A channel 50 communicates with the bottom of the lower portion 38 of the separation chamber 34 . Pressure within the separator tank 22 forces the oil collected in the lower portion 38 of the separation chamber 34 to flow through the channel 50 and back to the compression chamber of the compressor 14 to lubricate the rotary screws, the gearbox and other components.
[0025] FIGS. 3 - 6 and 8 - 9 schematically illustrate separator elements 54 used in the secondary separation process. Although the illustrated separator elements 54 may have slightly different configurations, with reference to FIG. 9, each separator element 54 generally has a cylindrical body comprising inner 55 and outer 56 perforate metal shells, filter media 57 sandwiched between the shells 55 and 56 , an open top 58 , a closed bottom 62 , and an internal passage (represented by arrow 64 ) where substantially oil-free compressed air flows from the separation chamber 34 of the separator tank 22 . During the secondary separation process, oil pooled in the bottom 62 of the separator element 54 will be piped back to the compressor 14 via a scavenging device as described in detail below. It should be noted that the present invention is capable of use with many different separator elements, and the separator elements 54 are merely shown and described as examples of such separator elements.
[0026] Referring now to FIG. 3, the separator element 54 is placed within the upper portion 42 of the separation chamber 34 . An annular flange 66 extends around the top portion 58 of the separator element 54 . The separator tank 22 includes a ledge 70 which extends circumferentially around an inner surface 74 of the side wall 30 of the separator tank 22 . The flange 66 of the separator element 54 rests on the ledge 70 of the side wall 30 . It should be noted that when the separator tank 22 is a cast separator tank, it is preferable for the ledge 70 to be an integrally cast member of the separator tank. As previously explained, air from the air/oil mixture introduced into the separation chamber 34 will flow upwardly into the upper portion 42 of the separation chamber 34 and through the separator element 54 .
[0027] The separator tank 22 includes an air exit port 78 in the side wall 30 of the separator tank 22 for the air from the air/oil mixture that flows through the separator element 54 . An MPCV assembly 82 is operatively connected, preferably threadably connected, to the air exit port 78 . Lid 86 is mounted on the separator tank 22 . When it is desirable to service or replace the separator element 54 , lid 86 is simply removed or pivoted out of the way to provide quick and easy access to the separator element 54 , without having to first disconnect the MPCV assembly 82 from the air exit port 78 .
[0028] In an alternative embodiment, a boss 90 (FIGS. 2 and 4) having a channel 94 (FIGS. 2 and 4) therethrough extends outwardly from the side wall 30 of the separator tank 22 . The boss 90 is arranged so that the air exit port 78 ′ (FIG. 4) in the side wall 30 aligns with the channel 94 to provide an air exit passageway 98 (FIG. 4) out of the upper portion 42 of the separation chamber 34 . MPCV assembly 82 (FIG. 4) is operatively connected to the channel 94 of the boss 90 . In a preferred embodiment, the separator tank 22 is a cast separator tank and the boss 90 is an integrally cast member of the separator tank 22 .
[0029] Referring again to FIG. 3, during operation of the compressor system 10 , an upwardly acting resultant force within the separation chamber 34 is applied against the bottom 62 of the separator element 54 . Thus, a separator element hold down mechanism 102 is provided between the separator element 54 and the lid 86 to position and hold the separator element 54 within the separation chamber 34 . The separator element hold down mechanism 102 , which is in the shape of an annular spacer ring, engages the flange 66 (or flange 66 ′ as shown in FIG. 8) of the separator element 54 to hold the separator element 54 against the ledge 70 on the side wall 30 when the lid 86 is closed. The separator element hold down mechanism 102 positions the separator element 54 away from the lid 86 , and it also includes a plurality of apertures 106 (or 106 ′ as shown in FIG. 8) or holes which allow the air to flow through the separator hold down mechanism 102 to reach the air exit port 78 (or 78 ′ as shown in FIG. 8) in the side wall 30 of the separator tank 22 . The separator element hold down mechanism according to the present invention may comprise many different shapes and configurations, so long as it functions to position and hold the separator element within the separation chamber, and so long as it allows the air which travels through the separator element to reach the air exit port in the side wall of the separator tank.
[0030] For example, with reference to FIG. 5, the separator element hold down mechanism 102 ′ includes a plurality of bolts 110 which threadably extend through the lid 86 ′ and which engage the flange 66 ′ of the separator element 54 to hold the separator element 54 against the ledge 70 on the side wall 30 . Each bolt 110 includes an O-ring seal 114 between itself and the lid 86 ′ to better seal the air space provided between the bottom of the lid 86 and the top 58 of the separator element 54 . Air flowing up, through the separator element 54 simply changes direction and flows out of the air exit port 78 ′ in the side wall 30 of the separator tank 22 .
[0031] As another example, with reference to FIGS. 6 - 7 , the separator element hold down mechanism 102 ″ is a generally annular spacer ring 118 having a top ring 122 , a bottom ring 126 , and a plurality of columns 130 extending between the top 122 and bottom 126 rings, thereby defining a plurality of air passages 134 . The spacer ring 118 engages the flange 66 ′ of the separator element 54 to hold the separator element against the ledge 70 on the side wall 30 when the lid 86 is closed. Air flowing up through the separator element 54 passes through the air passages 134 on its way to the air exit port 78 ′. In an alternative embodiment, the annular spacer ring is a solid cast annular ring having an aperture therethrough to allow the air passing through the separator element to reach the air exit port.
[0032] Preferably, ledge 70 on the side wall 30 of the separator tank 22 includes an annular groove 138 for receiving an O-ring seal 142 (see, e.g., FIG. 6). The O-ring seal 142 is positioned between the flange 66 ′ (or flange 66 as shown in FIG. 3) of the separator element 54 and the ledge 70 of the side wall 30 to provide an appropriate seal and to accommodate stack-up manufacturing/assembly tolerances in the separator tank assemblies shown in FIGS. 3 - 6 and 8 - 9 .
[0033] As mentioned above and with reference to FIG. 9, oil mist coalesced by the secondary separator element 54 is drawn inward towards passage 64 , runs down inner shell 55 and collects at the bottom 62 of the separator element 54 . The coalesced oil is drawn out of the bottom 62 of the separator element 54 by a separator element oil scavenge device 146 . The scavenged oil is piped back to the compressor 14 for use by the compressor 14 .
[0034] With continued reference to FIG. 9, the separator element oil scavenge device 146 includes a scavenge tube or pipe 150 . The tube is preferably a metal tube but, may be made of other suitable materials, such as plastic. One end 154 of the tube 150 is located near the bottom 62 of the separator element 54 . The tube 150 extends up through the passage 64 of the separator element 54 , and along and above the open end 58 of the separator element 54 . Although not shown, a support member may extend across the open end 58 of the separator element 54 . The tube 150 would then extend through the support member. The tube 150 extends back through the flange 66 ′ of the separator element 54 . The tube 150 also suitably extends through the spacer ring 118 . The tube 150 is preferably tack welded to either or both of the flange 66 ′ and support member (not shown) to locate the end 154 of the tube 150 a predetermined distance from the bottom 62 of the separator element 54 . Because the tube 150 is incorporated into the structure of the separator element 54 , during assembly of the separator tank 22 , no independent adjustment of the scavenge tube 150 is necessary to ensure that the tube 150 is spaced an optimum distance from the bottom 62 of the separator element 54 . A channel 158 is provided in the side wall 30 of the separator tank 22 . The channel 158 opens through the ledge 70 on the side wall 30 and is adapted to receive a portion of the tube 150 . An O-ring seal 162 is placed around end 164 of the tube 150 which extends through the flange 66 ′. The channel 158 is also adapted to receive the O-ring seal 162 to provide an appropriate seal.
[0035] Upon assembly of the separator tank 22 , the separator element 54 is placed within the separation chamber 34 such that the end 164 of the tube 150 extending through the flange 66 ′ is received by the channel 158 . As shown in FIG. 9, the tube 150 may be used as a handle for placing and removing the separator element 54 into and from the separator tank 22 . To replace the separator element 54 , the lid 86 is opened and the separator element 54 is removed without having to first disassemble the scavenge device 146 . To reinstall a separator element 54 into the separation chamber 34 , a separator element 54 and its securely attached scavenge device is simply deposited within the separation chamber 34 as described above. Once the lid 86 is closed, the separator hold down mechanism will hold the separator element in place.
[0036] [0036]FIG. 8 illustrates an alternative separator element oil scavenge device 146 ′ which includes a scavenge tube 166 , such as a Teflon tube. One end 170 of the tube 166 is connected to a fitting 174 found in the bottom 62 of the separator element 54 and the other end 178 of the tube 166 is connected to a fitting 182 extending through a channel 158 ′ in the side wall 30 of the separator tank 22 .
[0037] Variations and modifications of the foregoing are within the scope of the present invention. It is understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.
[0038] Various features of the invention are set forth in the following claims. | An air compressor system having an air/oil separator for use with an air compressor, the air/oil separator including a separator tank having a side wall with an air exit port; a separator element hold down mechanism between the separator element and a lid mounted on the separator tank; and a separator element oil scavenge device which scavenges oil from the bottom of the separator element and passes the scavenged oil through the side wall of the separator tank. A method of replacing a separation element in a separation chamber of the air/oil separator including the steps of removing the separator element from the separation chamber without disconnecting the scavenge device attached thereto, and positioning a replacement separator element within the separation chamber, such that a scavenge device securely affixed thereto is caused to communicate with the side wall of the separator tank. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention pertains to an apparatus and method of providing substantially improved radiation beams for the treatment of surfaces, thin films, coatings, fluids or objects. More particularly, the present invention pertains to an apparatus and method for optically combining the light output of at least two arrays of solid-state light emitters to produce a light beam that has a selected spectrum chosen for applications requiring a wide range of wavelengths to improve or accelerate a treatment process with a controllable irradiance.
[0003] 2. Description of the Prior Art
[0004] Radiant energy is used in a variety of manufacturing processes to treat surfaces, films, coatings, over layers, and bulk materials. Specific processes include but are not limited to curing, fixing, polymerization, oxidation, purification, or disinfections. By way of example, the manufacture of components for motor vehicles involves the application of under coatings, paints or clear coatings on vehicle surfaces for various purposes including corrosion resistance, decoration or surface protection (e.g. scratch resistance). The coatings or paints are resins or polymer-based materials that are applied as liquids or powders and require thermal or radiant energy processing to become solids. The processing of coatings or paints by thermal methods is slow and requires times ranging from minutes to hours to complete. In addition, some materials (for example, substrates or coating components) may be heat sensitive and damaged by thermal treatments.
[0005] Non-thermal curing using radiant energy to polymerize or effect a desired chemical change is rapid in comparison to thermal treatment. Radiation curing can also be localized in the sense that curing can preferentially take place where the radiation is applied. Curing can also be localized within the coating or thin film to interfacial regions or in the bulk of the coating or thin film. Control of the curing process is achieved through selection of the radiation source type, physical properties (for example, spectral characteristics), temporal variation, or the curing chemistry (for example, coating composition).
[0006] A variety of radiation sources are used for curing, fixing, polymerization, oxidation, purification, or disinfections of a variety of targets. Examples of such sources include but are not limited to photon, electron or ion beam sources. Typical photon beam sources include but are not limited to arc lamps, incandescent lamps, electrodeless lamps and a variety of electronic (that is lasers) and solid-state sources (that is solid state lasers, light-emitting diodes and diode lasers). Selection of a specific radiation source for an application is contingent on the requirements of the treatment process and the characteristics of the radiation source. These characteristics are related to but are not limited to the physical properties of the source, its efficiency, economics, or characteristics of the treatment process or target. For example, arc lamps or radio-frequency or microwave driven “electrodeless” ultra-violet sources efficiently produce high levels of radiated power having applications in many “industrial” processes where rapid treatment using significant levels of irradiance or energy density over large areas are needed. Arc or electrodeless lamps require high voltage, microwave or radio frequency power supplies and in the case of microwave-driven systems, a microwave tube (that is a magnetron). These high-powered lamps also require cooling and heat rejection systems. Such operational requirements limit the application of such photon sources to situations were this need can be met.
[0007] The spectral emissions of arc and electrodeless lamps are controlled by the conditions under which the lamp is operated, the particular gases used to fill the bulb and the selection of various additives placed in the bulb. Those skilled-in-the-art formulate specific lamp fills meeting curing needs for many photochemical processes, but gaps exist in spectral coverage in certain spectral ranges.
[0008] Solid-state light sources, such as, but not limited to, light emitting diodes (LEDs), diode lasers, diode pumped lasers and flash lamp-pumped solid-state lasers provide emission sources that can tuned to the needed wavelength or can be combined as arrays to provide a multi-wavelength source for applications needing broadband source. Advances in solid-state source technology provide high-brightness ultraviolet LEDs suitable as sources for radiation treatment.
[0009] At the present time, commercial UV emitting diodes emitting radiation down to an output of 370 nm. are available from Nichia, Cree, Agilent, Toyoda Gosei, Toshiba, Lumileds and Uniroyal Optoelectonics (Norlux).
[0010] UV emitting LEDs and laser diodes are constructed using large band gap host materials. InGaN based materials can be used in LEDs emitting at peak wavelengths ranging from 370 to 520 nm (for example, from the ultra-violet (UV-A) to visible green). The band gap of GaN is 3.39 eV and can accommodate luminescent transitions as large as 363 nm. The substitution of In into the GaN host provides localized states that can radiate in the ultraviolet down to 370 nm.
[0011] Other nitride materials such as InAlGaN can emit ultraviolet radiation in wavelengths as short as 315 nm. InAlGaN is already being used to make high brightness LEDs and laser diodes that operate in the range of 315 to 370 nm. Hirayama et al (Appl. Phys. Lett. 80,207 (2002)) reports devices employing layered structures of InxGa1-xN or quaternary InxAlyGa1-x-yN grown on AlxGa1-xN (x=0.12-0.4) have been used in multiple quantum well structures to produce sources emitting comparable flux at 330 nm to InGaN devices operating at 415-430 nm. Hirayama et al. (Hirayama et al, Appl. Phys. Lett, 80, 1589 (2002)) has also reported a room temperature LED source using an improved multiple quantum well (MQW) structure and InAlGaN materials which emits intense UV radiation at 320 nm and significant emission at 300 nm.
[0012] Hirayama et al. (Appl. Phys. Lett. 80, 37 (2002)) report that AlxGa1-xN(AlN)/AlyGa1-yN MQWs exhibit efficient photoluminescence between 230 to 280 nm and that the photoluminescence is as high as that of the InGaN-based materials used in the violet diodes now commercially available. AIN-based materials are likely candidates for making ultraviolet LEDs operating in the UV-B or UV-C ranges. Other researchers are studying carbide and diamond materials as hosts for deep-UV based on the fact that their band gaps are as large as AlN.
[0013] LEDs operating in the blue, violet and UV-A (390 nm) wavelengths are of sufficient radiance to be used in ultraviolet and photochemical curing as “spot” curing sources. U.S. Pat. No. 6,331,111B1 (Cao) and EP 0-780-104 (Breuer et al) describe hand held portable spot curing light systems using solid state light sources consisting of light emitting diodes or diode laser chips. The light source of Cao may contain sources that emit multiple wavelengths so that numerous components in materials whose photo initiators are sensitive to different wavelengths may be cured at once. In the preferred embodiment described in Cao, the light travels directly to the curing surface without going through an optical device like a light guide or optical fiber. Breuer et al. describe a similar device optimized to cure dental resins and also extend claims to apparatus where the irradiator is a stationary curing apparatus whose light source chips are fixed to the walls of the curing chamber.
[0014] Various light sources have been used for the purposes of curing composite materials. These include plasma, halogen, fluorescent, and arc lamps. Various lasers have been incorporated in curing apparatus. Lasers emitting ultraviolet beams include frequency doubled or re-doubled sources like the 266 nm Nd—YAG systems, argon-ion systems and Nd—YAG pumped OPOs (optical parametric oscillators). Cao cites U.S. Pat. Nos. 5,420,768, 5,395,769, 5,890,794 and 5,161,879 where LEDs have been employed as curing light sources. The application of solid state sources to the curing process are also described in U.S. Pat. Nos. 6,127,447 and 5,169,675.
[0015] Technology necessary for the application of solid-state sources in the treatment process can be found in the development of LED and laser diode equipped systems for illumination and solid-state displays. These systems include an apparatus for LED illumination that can be incorporated into a hand-held lamp, are battery powered and equipped with electronics that provide pulsed power to control lamp radiance and compensate for the decrease in battery voltage during battery discharge. Published U.S. Patent Application 2002/0017844 A1 teaches the use of optical systems to modify the field of view for LED emitters in displays where the field-of-view is restricted.
[0016] There are many examples in the prior art of the use of LEDs in arrays to synthesize multi wavelength emissions. U.S. Published Patent Application No. 2001/0032985 A1 teaches the installation of arrays of colored LEDs on a chip to make multicolored or white solid-state illumination sources. U.S. Pat. Nos. 6,016,038 and 6,150,774 disclose the method and electronics needed to generate complex, predesigned patterns of light in any environment. The use of computer controlled LED arrays to provide light sources capable of rapid changes in illumination and spectral selection are detailed in U.S. Pat. No. 6,211,626, which describes a system using sub-arrays of primary colored (red, green and blue) LEDs whose individual elements are addressable and which can be controlled by pulse modulation to emit varying amounts of light to synthesize a third color. U.S. Pat. No. 6,211,626 indicates that such computer-controlled arrays of light emitters are not new but that previous systems had limitations, which reduced the flexibility or efficiency of the illumination system. The use of computer control for lighting networks used in illumination is described in U.S. Pat. Nos. 5,420,482, 4,845,481 and 5,184,114.
[0017] U.S. Published Patent Application No 2002/0191394 teaches the use of a diffractive optical element (diffraction grating) for mixing light from monochromatic light sources like LEDs and making multicolor or white beams. The monochromatic light sources are positioned relative to the grating where light of that frequency is found in the diffracted order beams higher than the zeroth order. The mixed beam is the zeroth order beam. A white beam will be provided if sufficient frequencies are represented in the first and higher order beams being directed on the grating. Fraunhoffer diffraction is used to mix the monochromatic beams. This is different from the use of Fresnel Zone plates to accomplish the coupling of the multiple radiation sources
SUMMARY OF THE INVENTION
[0018] The present invention provides a solid-state light source and method which optically combines (mixes) the light output of at least two and preferably additional independently controllable discrete solid-state light emitter arrays to produce a light beam that has a selected multi-wavelength spectrum over a wide range of wavelengths such as from deep UV to near-IR to provide irradiance of a target surface with a controlled power level. Optical mixers combine light spectrums which are provided from the light emitter arrays to produce the controllable multi-wavelength spectrum.
[0019] Specific features of this light source permit changes in the spectral, spatial and temporal distribution of light for use in curing, surface modification and other applications.
[0020] This light source can be adjusted to precisely match the physical characteristics of the applied light to the chemical properties of materials to provide a means to improve the process at both nanometer and greater length scales by:
(1) optimizing the degree and rate of cross-linking of polymeric materials; (2) selecting specific cross-link bonding in polymers; (3) matching light source characteristics to specific photo-initiators; (4) controlling the distribution, penetration or rate of light energy deposition in materials to create new morphologies; and (5) optimizing light source characteristics for surface processing.
[0026] A preferred embodiment of the invention comprises at least two solid state light emitting arrays which preferably are LED arrays, each of which has a characteristic emitting frequency (wavelength), an optical mixer to mix the radiation from the LED arrays, a reflector to concentrate radiation from the arrays and to provide a two-dimensional energy distribution on the target surface to be treated which is optionally substantially uniform. An optional cooling system may be provided to provide high stability of the spectral output and to improve lifetime of arrays.
[0027] The invention increases the flexibility of the photochemical processes (especially, but not limited to, UV-curing of inks and the like, plastic, thermal paper, liquid crystal and the like) by either optimizing existing ultraviolet treatment processes and outcomes, or creating entirely new treatment processes or outcomes. The invention performs these tasks by providing a light source whose spectral emissions can be varied to provide changes in the ultraviolet light such as to changes in the brightness, chromaticity, calorimetric purity, hue, saturation and lightness of visible light. Modification of physical characteristics of light provides configuration of a light source to make the best use of the physical and chemical properties of curable materials.
[0028] Other problems which the invention overcomes include curing applications where the use of technology normally included in light sources cannot be used for technical, process or economic reasons. This includes but is not limited to:
[0000] (1) high voltage cabling, electronics and power supplies;
[0000] (2) RF or microwave cabling, wave guides, electronics and power supplies;
[0000] (3) gaseous electronic components including electrode and electrode-less bulbs
[0000] (4) high power electronics and the needed heat dissipation systems.
[0029] The invention also provides a solution to the problem of unwanted light emissions such as infrared from curing sources. Ultra-violet solid-state light emitter arrays generate little or no emissions in the infrared. If infrared radiation is needed in the curing process, infrared emitters of the desired wavelength and energy can be configured into the solid state UV generating arrays providing the selected wavelengths which are included in the curing light system to provide the desired missed spectrum.
[0030] The frequency spectrum of the individual light emitting arrays is chosen either (1) to provide a composite frequency made up of the mixed spectrum from the individual arrays required for the desired application, or (2) each array provides the identical common frequency spectrum to increase the power level of irradiance of the common frequency spectrum.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1A is a side elevational view of a first embodiment of the present invention; FIG. 1B is a perspective view of the first embodiment of the present invention; and FIG. 1C is an example of a light emitting array which may be used with the practice of the various embodiments of the invention.
[0032] FIG. 2 is the spectral distribution of irradiance of one of the LED arrays in FIG. 1 showing ultraviolet radiation source emission near 390 nanometers.
[0033] FIG. 3 is a spectral distribution of irradiance of the other LED array in FIG. 1 showing an ultraviolet radiation emission near 410 nanometers.
[0034] FIG. 4 is a spectral distribution of irradiance produced by optical mixing of the individual spectral radiance distribution of the LED arrays of the embodiment of FIG. 1 with the spectrums illustrated in FIGS. 2 and 3 .
[0035] FIG. 5 is a spectral distribution of irradiance of the individual LED arrays showing the individual components of FIGS. 2 and 3 and the optical mixing thereof as illustrated in FIG. 4 .
[0036] FIG. 6 is a comparison between measured and simulated spectral irradiance showing simulated spectral irradiance as a line and a measured spectral irradiance as diamonds regarding the embodiment of FIG. 1 .
[0037] FIG. 7 is a spectral distribution of irradiance of the embodiment of FIG. 1 operated with the 390 nm LED array operated with a bias voltage of 47 volts and the 405 nm LED array operated at a bias voltage 0, 34, 35, and 38 volts respectively.
[0038] FIG. 8 shows an embodiment of the invention using two solid state light emitting arrays as illustrated in FIG. 1 , including a housing with an interior elliptical reflector installed in a lamp enclosure providing cooling to the solid state light emitting arrays and a controller for controlling the power and spectral output produced by the individual solid state light emitting arrays.
[0039] FIG. 9 is a perspective view of a second embodiment of the invention utilizing three solid state light emitting arrays, three semitransparent mirrors functioning as optical mixers and an interior cylindrical reflector.
[0040] FIGS. 10A and 10B show a simulated flux distribution of the second embodiment of FIG. 9 .
[0041] FIG. 11 illustrates a perspective view of a third embodiment of the invention in which four solid state light emitting arrays are placed between four semitransparent mirrors functioning as optical mixing elements and an interior cylindrical reflector.
[0042] FIG. 12 is a perspective view of a fourth embodiment of the invention with four solid state light emitting arrays placed on the edges of four optical mixers and a cylindrical interior reflector.
[0043] FIG. 13 is a perspective view of a fifth embodiment of the invention with six solid state light emitting arrays placed between six optical mixing elements.
[0044] FIG. 14 is a perspective view of a sixth embodiment of the invention with six solid state light emitting arrays placed on edges of six optical mixing elements.
[0045] FIG. 15 is a perspective view of an seventh embodiment of the invention with six solid state light emitting arrays arranged facing eight optical mixers arranged in an octahedron.
[0046] FIG. 16 is a perspective view of an eighth embodiment of the invention with six solid state light emitting arrays facing eight optical mixers.
[0047] FIG. 17 is a perspective view of a ninth embodiment of the invention of eight solid state light emitting arrays facing four optical mixers arranged to face a structure with tetrahedral symmetry.
[0048] FIG. 18 is a perspective view of an tenth embodiment of the invention with four solid state light emitting arrays spaced between four intersecting optical mixing elements contained in an internal ellipsoidal reflector.
[0049] FIG. 19 shows the flux distribution of the ninth embodiment of FIG. 18 .
[0050] FIG. 20 is a perspective view of an eleventh embodiment of the invention with two elongated solid state light emitting arrays facing an optical mixer contained in an internally reflective elliptical reflector.
[0051] FIG. 21 is a perspective view of a twelfth embodiment of the invention with two elongated solid state light emitting arrays facing a prismatic mixing device contained in an elliptical reflector.
[0052] FIG. 22 is a perspective view of a thirteenth embodiment of the invention with two elongated solid state light emitting arrays facing one optical mixing element contained in a reflector with an elliptical cross section.
[0053] Like reference numerals identify like parts throughout the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0054] The present invention is a solid state light source and a method of irradiating a target surface with a solid state light source which utilizes solid state light emitting arrays each preferably comprising a plurality of light emitting diodes (LEDs) which are mounted on a flat surface. Each diode emits light away from one side of the flat surface toward a target surface with at least one wavelength which is chosen to satisfy the desired application. At least one optical mixer is provided with each mixer mixing the output of a pair of solid state light emitting arrays. Each optical mixer is positioned symmetrically with respect to a pair of light emitting solid state arrays. Each optical mixer reflects part of the light output from a symmetrically disposed diode array and transmits part of the light output from another symmetrically disposed light array to provide a composite mixed light spectrum to irradiate the target surface with mixed light which has a selected frequency spectrum with the irradiance level of the spectrum being controllable by a variable control parameter such as voltage, but it should be understood that the invention is not limited thereto. The at least one optical mixer may be designed to substantially split (50-50) the light incident thereon from each array into a part which is reflected and a part which is transmitted through the optical mixer. With respect to the portion of the light which is transmitted through the optical mixer from the first light emitting array, the light incident on an opposite surface of the optical mixer from the other light emitting array which is reflected is optically mixed with the portion transmitted through the optical mixer from the first light emitting array. A composite wave front comprised of the mixed components of light from each of the symmetrically disposed solid state light emitting arrays is transmitted toward the irradiated target surface. As is described below, a controller controls the power applied to the light emitting arrays to control the irradiance which is incident on the target surface. Each light emitting array may have a substantially similar frequency spectrum or have a different frequency spectrum.
[0055] When the frequency spectrums of the symmetrically disposed light emitting arrays are different, the overall frequency of the irradiance on the target surface is a summation of the individual frequency spectrum output by the individual light emitting arrays. In each of the embodiments of the invention, mixing is produced by one or more optical mixers which may be a partially reflective and partially transmissive mirrors which may transmit and reflect substantially equal parts or transmit and reflect unequal parts or a prism which is irradiated by the light from the individual solid state light arrays to provide mixing thereof.
[0056] FIGS. 1A and 1B illustrate a first embodiment 10 of the present invention. FIG. 1A is an elevational view with a section taken through a curved internally reflective housing 21 ; FIG. 1B is a perspective view of the embodiment 10 ; and FIG. 1C is an illustration of a suitable light emitting array which may be used with the practice of the invention.
[0057] The first embodiment 10 is illustrative of a basic solid state light source in accordance with the present invention. Each of light emitting arrays 12 A and 12 B may be manufactured in accordance with any well-known technique. The surface 14 of each of the pair of symmetrically disposed solid state light emitting arrays which, in a preferred embodiment, are LEDs output light rays 16 which pass directly to the target surface 18 . Other light rays 17 produce a combined irradiance produced by optical mixing element 20 on which the rays 17 are incident thereon. As may be seen in FIG. 1A , the interior of housing 21 has an internally reflective surface 22 which functions to reflect any light output from either of the light emitting arrays 12 A or 12 B toward the target surface 18 to provide controlled irradiance which, in a preferred embodiment, is preferably substantially uniform thereon as described below in conjunction with FIGS. 2-6 in view of the curvature of surface 22 being elliptical with the optical mixer being near the focal axis of the elliptical curvature. Light rays 16 , 17 and 19 , which are output from the light emitting arrays 12 A and 12 B and do not pass through the optical mixer 20 , are shown as solid lines and light rays 22 passing through the optical mixer 20 , from either of the light emitting arrays 12 A or 12 B are shown as dotted rays. Parallel solid line rays 19 and dotted rays 22 symbolize the net mixing performed by the optical mixer 20 for the rays emitted from the surfaces of the light emitting arrays 12 A and 12 B which partially transmits and partially reflects the light emitted from the pair of light emitting arrays. The degree of reflection and transmission may be varied from an equal splitting.
[0058] The housing 21 , while preferably having an elliptical cross section, may utilize other curved cross sections which facilitates converging divergent light rays produced by the solid state light arrays 12 A and 12 B being directed toward the target surface 18 as indicated by arrows 24 .
[0059] The pair of light emitting arrays 12 A and 12 B are illustrated as square flat panels. The light emitting arrays are comprised of a plurality of devices, such as LEDs, which emit radiation in the ultraviolet range but the invention is not limited thereto with a suitable construction being described below in conjunction with FIG. 1C . For example, in a high power irradiation apparatus in accordance with the embodiment 10 of FIGS. 1A and 1B , the arrays 12 A and 12 B may respectively be an array of 40 LEDs as described in FIG. 1C which individually emit at 400 mW at 405 nm mounted on an integrated circuit of approximately 1 square cm. The other radiation source 12 B may, without limitation, be an array of 40 LEDs as described below emitting 100 mW at 390 nm mounted on an integrated circuit of approximately 1 square cm. Additionally, the optical mixing element 20 may be semi-reflective mirror which substantially equally splits the emission from the rays 16 into reflected rays 19 and transmitted rays 22 which are mixed as indicated by the aforementioned parallel solid and dotted lines 19 and 22 such that the rays are superimposed onto each other. A semi-reflective mirror, which may be utilized as the optical mixer 20 , may be a UV transmitting quartz plate that is coated with a thin chromium film that reflects and transmits approximately 50% of the incident light. The light emitting diode arrays 12 A and 12 B are symmetrically positioned with respect to the optical mixer 20 such that virtual images of radiation sources are superimposed to create in a preferred embodiment a mixed light source comprising substantially equal amounts of light from each of the light emitting arrays.
[0060] FIG. 1C illustrates a suitable construction for the light emitting solid state arrays 12 A and 12 B with a scale of approximately 5:1 for the first embodiment as described above and in the embodiments as described below. The array 60 is comprised of 40 LEDs 62 . A lower bus bar 64 has a group of 8 LEDs mounted thereon. Each of the LEDs 62 mounted on the lower bus bar 64 are in turn coupled by a wire 66 by means of wire bonds 68 which connect the wire extending from the individual LEDs to four upper bus bars 64 on which 4 LEDs are mounted. A lens 70 focuses light emitted by the individual LEDs 62 toward the optical mixer 20 . A thermal sensor 72 is utilized to provide temperature control for the LED array 60 . The LED array 60 is mounted on a hexagonal substrate 74 . Electrical terminals 76 are mounted on the hexagonal substrate 74 to provide suitable electrical contacts for electrical power of the array.
[0061] The light source represented by the light emitting solid state arrays 12 A and 12 B and the optical mixer 20 is positioned approximately at the focus of the elliptical reflector 22 which is preferably substantially one-half of an ellipse. However, the reflector 22 may be more or less than one-half of an ellipse if desired and may be a non-elliptical surface. Since the reflector 22 is part of an ellipse, the reflector 22 has a major axis, a minor axis, a first focal axis within the reflector, and a second focal axis outside the reflector. The light source comprised of the aforementioned light emitting and optical mixer is preferably positioned on the first focal axis. Light beams from the arrays of diodes 12 A and 12 B are transmitted and reflected by the optical mixer 20 and strike the elliptical reflector 22 that directs the light beams to the second focal axis of the elliptical reflector 22 proximate to the target surface 18 . The target surface 18 is placed substantially at the second focal axis where the light beams are directed to strike the irradiated surface thereof. The location of the target surface 18 at the second focal axis maximizes the irradiance at the second focal axis. The irradiated surface 60 can also be placed beyond the second focal axis such as at the far field to increase the area which is irradiated.
[0062] FIGS. 2-6 illustrate the optical performance of the radiation on the target surface 18 using the first embodiment 10 . The spectral readings were obtained using an integrated sphere and a spectral radiometer (Ocean Optics model S2000) based on techniques well-known in the field of illumination. The radiation sources were 40 light emitting diodes which are high flux density solid state modules manufactured by Norlux Monochromatic Hex (NHX) emitting either ultraviolet UV-A at a peak emission at 390 nm or ultraviolet UV-B at 405 nm with a peak emission at 410 nm. The LED arrays 12 A and 12 B were independently connected to DC power supplies operated at a constant voltage mode. A forward bias voltage turned the diodes on to produce the UV spectra of FIGS. 2-6 .
[0063] FIGS. 2 and 3 show the spectral irradiance of the source 12 A which is a UV-A emitter and the source 12 B which is a UV-B emitter. Radiation source 12 A was operated at forward bias of 15.6 volts and a current of 200 nA. Array 12 A emitted UV-A ultra-violet radiation that peaked at 395 nm and extended from 385 to 405 nm (Full-Width-at-Half-Maximum) (FWHM). Diode array 12 B was operated at a forward bias of 19 volts and a current of 200 mA to produce UV-B ultraviolet radiation that peaked at 410 nm and extended from 400 to 418 nm (FWHM).
[0064] FIG. 4 shows a measured spectral radiance of embodiment 10 when both radiation sources 12 A and 12 B were operated simultaneously. The composite spectrum peaked at 410 nm and extends from 392 to 418 nm FWHM. The LED array 12 A was operated at 15.6 volt forward bias, whereas the LED array 12 B was operated at 17.5 volts forward bias. The spectrum is a composite of the summed emission from the two LED arrays 12 A and 12 B.
[0065] FIG. 5 illustrates the simulated spectrum produced by the summation of the individual emission spectra of the diode arrays 12 A and 12 B illustrated in FIGS. 2 and 3 .
[0066] FIG. 6 is a comparison of the simulated and measured spectra of the embodiment 10 . The measured spectra are identified by diamonds and simulated spectra are identified by lines. The measured spectrum matched a simulated spectrum over the entire range of emission from the light emitting arrays 12 A and 12 B and shows an excellent mixing of the beams from the two radiation sources.
[0067] The power levels of the light from the light emitting arrays 12 A and 12 B are controlled by varying the electrical bias applied thereto which changes the forward bias current of the diodes. The variation of voltage or another electrical parameter of the individual light emitting arrays 12 A and 12 B permits the variation of the spectral characteristic of the mixed light by choosing the magnitude and frequency of the spectra that are mixed by the optical mixer 20 .
[0068] FIG. 7 shows how the spectral composition of a beam from the embodiment 10 can be changed continuously from (1) a spectrum 90 representing the wavelengths from the diode array 12 A, (2) a spectrum 92 with equivalent contributions from the diode arrays 12 A and 12 B, (3) a spectrum 94 with an increased spectrum from the array 12 B, and (4) finally to a spectrum 96 with the dominant contribution from the array 12 B. This demonstrates an important function of the embodiments of the invention including the representation of the spectral composition of FIG. 1 which permits generation of a spectrum with variable ultraviolet spectral weight.
[0069] FIG. 8 illustrates a system 120 incorporating the embodiment 10 of FIG. 1 into a lamp housing 130 which is equipped with a cooling system for the LED arrays 12 A and 12 B. The air cooling system may be by forced air utilizing one or more fans inducting air into the housing and blown past the interior curved reflector 21 . As may be seen, pathways exist for the ingress and egress of cooling air. A controller 170 is coupled via connection 172 to the solid state light source. The curved reflector 21 is mounted in the lamp housing 130 with the reflector being attached to a base of the lamp enclosure that has a rectangular opening 180 from which light rays 182 pass to the target surface 18 . The LED arrays 12 A and 12 B are air cooled by two fans 162 which push air into the lamp enclosure 130 . A slot 190 is cut into the curved reflective surface 21 to permit air to be pushed into the lamp enclosure 192 to allow the air to impinge on heat sinks 194 of the LED arrays 12 A and 12 B which are attached thereto. The fans 162 may be powered from a 12 volt power supply. The LED arrays 12 A and 12 B will suffer a loss of light emitting power if a surface temperature of the substrate to which the LEDs 12 A and 12 B are attached exceeds 40° C. with current commercially available products. The power to the diode arrays 12 A and 12 B and the speed of the fans 162 is adjusted to keep the LED chip surfaces below the maximum temperature, such as 40° C. The controller 170 may be digitally controlled which permits programming of the voltage to be applied to each of the diode arrays 12 A and 12 B in order to produce a variation in the summed output radiation as reflected, for example by the curves 90 - 96 in FIG. 7 once the frequency spectra is determined by the choice of the individual solid state light emitting elements of the array.
[0070] FIG. 9 illustrates a third embodiment 230 of a solid state light source in accordance with the invention which is comprised of three LED arrays 232 A, 232 B and 232 C and three optical mixers 250 which intersect at a central point 252 within cylindrical reflector 254 . The three LED arrays 232 A, 232 B, and 232 C produce spectra which are mixed by the symmetrically disposed optical mixer 250 located therebetween. The aforementioned LED arrays and symmetrically positioned optical mixtures 250 perform the same function as described above with respect to the first embodiment 10 of FIG. 1 . The individual optical mixers 250 which intersect at central point 252 have an occluded angle of 120° between the adjacent optical mixers. The optical mixers 250 preferably are semi-reflective mirrors which split the emission substantially equally from the LED arrays 232 A, 232 B and 232 C into three transmitted and reflected beams of substantially equal intensity which are superimposed onto each other as indicated in FIG. 1 by the superimposed light rays 19 and 22 . However, this embodiment may use optical mixers which do not transmit and reflect equal parts. The three optical mixers 250 are symmetrical when rotated through an angle of 120°.
[0071] FIGS. 10A and 10B show the results of ray tracing simulations to predict the irradiance distribution 272 in the XZ plane as illustrated in FIGS. 10A and 10B for the second embodiment 230 . The radiance profiles for traces parallel and perpendicular to the X or Z axis through the center of the irradiance distribution show small asymmetry 272 . The asymmetry is a consequence of a lack of symmetry of the embodiment 230 to rotations 90° along an axis perpendicular to the XZ plane through the center of the embodiment 230 .
[0072] FIGS. 11 and 12 respectively show a third and fourth embodiment 360 and 400 . The designs respectively differ in the placement of the four LED arrays 232 A- 232 D arrays relative to the intersection 362 of the placement of the optical mixers 350 so that the diode arrays 332 A- 332 D are positioned between the edges 352 in FIG. 11 and face the edges 350 in FIG. 12 . In the third embodiment 340 , the LED arrays 332 A- 332 D face the point of intersection 362 while in the fourth embodiment 370 , the light emitting arrays 332 A- 332 D face the edges 352 of the optical mixers 350 . In the third and fourth embodiments, a cylindrical internally reflective housing 360 contains the LED arrays 332 A- 332 D and the four optical mixers 350 centrally disposed relative thereto which are joined together at central location 362 to form a cross. In the fourth embodiment 370 a solid line indicates light rays which are visible to the viewer and a dotted line indicates rays which are occluded from direct view. It should be understood that the connections to a suitable controller and cooling system for the light emitting arrays, such as illustrated in FIG. 8 , are not illustrated for purposes of simplifying the illustration.
[0073] FIGS. 13 and 14 show fifth and sixth embodiments 400 and 420 respectively of the invention which have been simplified to only show the LED arrays emitted. The internally reflective curved housing has been omitted along with the controller of the individual LED arrays which is used to produce a controlled application of power to the individual LED arrays to produce a variable spectrum as discussed above. The embodiment 400 of FIG. 13 has three pairs of LED arrays 432 A and 432 B which are symmetrically disposed relative to optical mixers 440 . Pairs of LED arrays 432 A and 432 B work in concert with their centrally disclosed optical mixer 440 to provide the same function as described above with respect to the first embodiment 10 to produce a controlled mixing of the light emitted from the surface of the pairs of the LED arrays. The difference between the embodiments 400 and 420 resides in the respective placement of the pairs of LED arrays 432 A and 432 B relative to the optical mixers 440 . In the embodiment of 400 , the pairs 432 A and 432 B face the point of intersection 442 of the optical mixers 440 and in the embodiment 420 , the pairs 432 A and 432 B face the edges 444 of the optical mixers 440 . The six optical mixers 440 are joined together at a central location 442 which is centrally disposed relative to the faces of the LED arrays 432 A and 432 B. The light from the three pairs of LED arrays 432 A and 432 B are combined by transmission and reflection of the six optical mixers 440 in accordance with the principal operation described above. While not illustrated, the embodiments 400 and 420 of FIGS. 13 and 14 may be placed inside of a cylindrical internally reflective housing of the type illustrated in FIGS. 1, 9 , 10 and 11 so as to cause light to be transmitted toward a target surface 18 . Additionally, a controller and a cooling system, such as that described above with respect to FIG. 8 , may be utilized to control the emission of light from the LED arrays. The six optical mixers 440 in the embodiments 400 and 420 form a cross at a point of intersection 442 and preferably have the characteristic of reflecting and transmitting substantially equal intensity light. A solid line indicates light rays which are visible to the viewer and a dotted line indicates rays which are occluded from direct view.
[0074] FIG. 15 shows a seventh embodiment 500 having three pairs of light emitting diode arrays 532 A and 532 B which are symmetrically disposed about eight optical mixers 550 which are triangular semi-transparent mirrors which function to split the irradiation sources 532 A and 532 B into transmitted and reflected beams of substantially equal intensity which are superimposed onto each other in accordance with the mixing function as described above with respect to the first embodiment of FIG. 1 . The LED arrays 532 A and 532 B are placed at the vertices placed at the edges of the optical mixers 550 . It should be noted that the curved internally reflective housing, controller and target surface have been omitted from the embodiment of FIG. 15 . A solid line indicates light rays which are visible to the viewer and a dotted line indicates rays which are occluded from direct view.
[0075] The eighth embodiment 560 of FIG. 16 utilizes three pairs of LED arrays 532 A and 532 B which are positioned at the vertices of twelve optical mixers 550 which are partially reflective mirrors. Mixing of light from pairs of LED arrays 532 A and 532 B occurs in the manner described above. A solid line indicates light rays which are visible to the viewer and a dotted line indicates rays which are occluded from direct view.
[0076] FIG. 17 illustrates a ninth embodiment 600 having four pairs of LED arrays 632 A and 632 B which face four optical mixers 650 configured in a structure with tetrahedral symmetry. It should be understood that the connections to a suitable controller and cooling system for the LED arrays, such as illustrated in FIG. 8 , are not illustrated for purposes of simplifying the illustration. A solid line indicates light rays which are visible to the viewer and a dotted line indicates rays which are occluded from direct view.
[0077] FIG. 18 shows a tenth embodiment 700 of the present invention having a configuration of four LED arrays 332 A, 332 B, 332 C and 332 D symmetrically disposed about four optical mixers 350 in a configuration similar to FIG. 11 except that an ellipsoidal reflector 740 is provided as the housing. The ellipsoid 740 has a major access, which is also the axis of rotation of the ellipse that sweeps out the surface of the ellipsoid, a minor axis, a first focus within the ellipsoid and a second focus outside the ellipsoid which are not illustrated. The LED radiation source is positioned on the major axis of the ellipsoid reflector 740 at the first focus. Since the irradiation source is extended, the image of the irradiation source will not be brought into sharp focus. As described above with respect to other embodiments, the internally reflective curved cylindrical housing, controller and cooling system have been omitted. A solid line indicates light rays which are visible to the viewer and a dotted line indicates rays which are occluded from direct view.
[0078] FIG. 19 shows the simulated irradiance of the embodiment 700 of FIG. 18 on the irradiated surface 18 . The radiance pattern of the beam shows a ring-like pattern near the peak irradiance. This pattern is due to the placement of the radiation sources 332 A- 332 D in a circle about the optical mixers 350 . As described above with respect to other embodiments, the internally reflective curved cylindrical housing, controller, cooling system and target surface have been emitted.
[0079] FIGS. 20 and 21 show eleventh and twelfth embodiments 800 and 900 of the present invention that utilize elongated linear arrays of diodes 12 A′ and 12 B′ with the embodiment 800 having elongated optical mixer 20 ′ which is a semitransparent mirror and the embodiment 900 utilizing an optical mixer 902 which is a prism for splitting and mixing beams from the arrays 12 A′ and 12 B′ using internal reflection rather than reflection from a mirror. As described above with respect to other embodiments, the internally reflective curved cylindrical housing, controller and cooling system have been emitted.
[0080] FIG. 22 shows a twelfth embodiment 1000 which is similar to the embodiment 800 of FIG. 20 regarding the configuration of the elongated light emitting diode arrays 12 A′ and 12 B′ and the elongated optical mixer 20 ′. The embodiment 1000 differs with regard to the curved internally reflective housing 1002 which is an elliptical reflector with a side reflector as an ellipse with semi-major and semi-minor axis being parallel and perpendicular to the optical mixer 20 ′ or a prism such as 902 used in the embodiment 900 of FIG. 21 and replacement thereof. The side reflector 1004 is attached to an elliptical plate 1006 to form an elliptical housing. As described above with respect to other embodiments, the internally reflective curved cylindrical housing, controller, cooling system and target surface have been emitted.
[0081] While the invention has been described in terms of its preferred embodiments, it is intended that numerous modifications can be made thereto without departing from the spirit and scope of the invention as defined in the appended claims. It is intended that all such modifications fall within the scope of the appended claims. | The systems and methods described herein relate to solid-state light sources capable of generating radiation beams for, but not limited to, the treatment of surfaces, bulk materials, films, and coatings. The solid-state ultraviolet source optically combines the light output of at least two and preferably as many four independently controllable discrete solid-state light emitters to produce a light beam that has a controllable multi-wavelength spectrum over a wide range of wavelengths (i.e. deep UV to near-IR). Specific features of this light source permit changes in the spectral, spatial and temporal distribution of light for use in curing, surface modification and other applications. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to electric motor structure and more particularly to an improved drain structure for a vertically mounted electric motor to be positioned below a liquid sump into which the rotor shaft of the motor can be connected.
It is generally well known to mount an electric motor below a liquid sump to connect the motor to a sump pump or the like, such as in dishwasher applications. Liquid leakage may sometimes occur along the seal between the sump pump and the rotor shaft, the leakage, if not noticed and stopped, exposing the several parts of the motor to what could prove to be serious damage.
Various types of arrangements have been utilized to direct liquid leakage from the sump away from the electric motor, including splash guards mounted on the rotor shaft between the seal and the endshield and more recently the structural arrangement, as disclosed in U.S. Pat. No. 4,535,262, has been utilized wherein the endshield itself is contoured to direct liquid to drain holes in the endshield for discharge of the liquid at a location removed from the motor parts. These past arrangements, for the most part, have been comparatively complex and expensive in manufacture and assembly and particularly have failed to be effective in situations where the upper surface of the endshield has been utilized to gather and drain liquids with an external rotating part thereabove, the rotating part often throwing or misting the liquid on the upper surface of the endshield so that it might coat exposed parts adjacent the motor as well as in the motor.
The present invention, recognizing the problems of the various structures of the past, including those of the more recent past, provides an improved drain structure for an electric motor which is comparatively straightforward and inexpensive in manufacture and assembly and yet assures proper removal and drainage of any liquid leakage from a sump above the motor, even though the upper endshield of such motor structure might further include an external rotating part thereabove. In addition, the present invention recognizes and resolves problems associated with formation of liquid menisci, as well as the undesirability of uncontrolled liquid sprays and mist, particularly in instances where rotating parts external of the motor and below the sump are utilized, the present invention providing a unique structural arrangement to avoid any such structural problems.
Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth herein.
SUMMARY OF THE INVENTION
More particularly, the present invention provides an improved drain structure for a vertically mounted electric motor to be positioned below a liquid sump into which the motor shaft of the motor can be connected comprising: an electric motor including an upper endshield surrounding at least a portion of the stator and rotor assembly of the motor, the endshield having the rotor shaft of the motor extending therethrough; a liquid drip pan mounted above the endshield, the drip pan having an aperture therein through which the rotor shaft passes, the pan having an upwardly extending peripheral side wall; drain means communicating with the peripheral side wall of the drip pan and extending laterally outward therefrom beyond the outer extremities of the upper endshield of the motor to isolate liquid from the several parts of the motor; and, liquid slinger means fixed in sealed relation to the rotor shaft above the liquid drip pan to sling liquid leakage in a radially outward direction below the upper edge of the drip pan side wall to be drained through the drain means. In addition, the present invention provides opposed laterally spaced overlapping lip members on the liquid slinger and drain respectively, the lips being so spaced and positioned that meniscus liquid leakage is prevented. Further, the present invention provides drain pan structure which guides liquid leakage to a preselected location, and also provides a unique way of removably mounting the liquid pan on the motor endshield to ensure gravity drainage.
It is to be understood that various changes can be made by one skilled in the art in the arrangement, form and construction of the several parts of the apparatus disclosed herein without departing from the scope or spirit of the present invention. For example, the type, shape and positioning of the liquid drip pan and associated drain troughs could be varied, the overlapping menisci controlling lip positions and form could be changed, and the liquid slinger form and contour could be modified without departing from the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings which disclose one advantageous embodiment of the present invention:
FIG. 1 is a cross-sectional view of the upper portion of a typical electric motor (parts of which are not shown to simplify illustration), incorporating the inventive drain assembly;
FIG. 2 is a perspective upper view of the upper portion of the drip pan comprising a part of the inventive structure;
FIG. 3 is a perspective, partially broken away view of the slinger ring which is mounted on the rotor shaft as disclosed in FIG. 1; and,
FIG. 4 is a top plan view of the motor structure and drain assembly of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 of the drawings, motor 2, which can be an induction type motor and of which only the upper portion is shown for purposes of simplification, includes a stator and rotor assembly with a rotor shaft vertically extending therefrom journalled in the end walls of endshields which surround the stator and rotor assembly, there being shown in FIG. 1 the upper portion of stator 3, the upper portion of upper endshield 4, the upper portion of rotor shaft 6 and centrally disposed upper cradle and bearing assembly 7 formed in the end wall 8 of upper endshield 4. Advantageously, upper endshield 4 can be of a one-piece diecast construction mold formed from a suitable aluminum alloy or the like. Endshield 4, which includes end wall 8 with the central disposed cradle and bearing assembly 7, also includes the downwardly depending peripheral side wall and spaced opposed upwardly extending vertical male standards 11 substantially adjacent and above downwardly extending side wall 9.
As can be seen in FIGS. 1 and 2, standards 11 matingly engage with substantially equally spaced female socket members 12 extending from the drain troughs of the lower face of a liquid drip pan 13 to hold drip pan 13 in a substantially horizontal position a preselected distance above end wall 8 of endshield 4. Pan 13 and socket members 12 can be formed integrally from any one of a number of suitable sturdy liquid resistant materials, such as plastic and, in accordance with the present invention, the manufacturing tolerances between the mating standards 11 and socket members 12 are selectively such that, in the event of any inaccurate fit, the pan 13 would bow downwardly toward its peripheral edge.
As disclosed in FIGS. 1 and 2 of the drawings, drip pan 13 has a central circular aperture 14 therein through which rotor shaft 6 freely passes when the pan is mounted on standards 11 of the endshield 4. The pan 13 is formed to further provide an integral upwardly extending vertical lip or weir member 16 surrounding aperture 14 as well as an upwardly extending vertical peripheral side wall 17. Wall 17 which serves as a liquid baffle and is of preselected height has opposed drain openings 18 and integral with and extending laterally outward in communication with drain openings 18 as part of pan 13 are a pair of opposed drain troughs 19, the side wall 17 extending in a downwardly sloping fashion along the opposed side edges of the drain troughs.
Referring to FIG. 1, it is to be noted that drain troughs 19 which can be an integral part of drip pan 13, as shown, are sized to extend laterally outward beyond the outer extremities of the upper endshield 4 for motor 2 so as to be capable of isolating any liquid leakage into drip pan 13 from the several parts of motor 2. As can be seen in FIG. 4, each trough 19 is designed to neck inwardly as it extends outwardly in a funnelling manner and, as can be seen in FIG. 2, each trough terminates at its lower surface in a downwardly extending, outwardly sloping drain lip 21 to further ensure liquid draining beyond the upper endshield of the motor. It is to be noted in FIG. 4, that the endshield 4 can be provided with a plurality of apertured bosses 22 (shown in FIG. 4 only). These bosses 22 serve to receive appropriate bolt and nut assemblies (not shown) to support motor 2 below an appropriately bottom sealed liquid sump of a dishwasher, or the like, having a part such as an internal pump to which rotor shaft 6 can be connected (also not shown). It also will be noted in FIG. 4 that standards 11 are so positioned as to mount liquid drip pan 13 horizontally in such a fashion that troughs 19 extend intermediate bosses 22.
Referring to FIGS. 1 and 3, mounted above liquid drip pan 13 is a flat, annular, liquid resistant slinger ring 23 which can be formed from any one of a number of suitable liquid resistant materials such as a flexible rubber. Ring 23 is so formed that its upper peripheral edge is rounded at 24. Advantageously, this rounding has a minimum curvature radius of approximately 0.125 inches, the rounding serving to assure liquid slinging and to minimize liquid spray beyond side wall 17 of drip pan 13. Ring 23 is provided with a collar member 26 integral with and extending downwardly from the periphery of central aperture 27 of ring 23. The aperture 27 and collar member 26 are so sized that collar member 26 snugly engages in liquid sealing relation with rotor shaft 6 about which it is fixedly mounted. The extremity of collar member 26 engages a stop ring 28 mounted in a groove on shaft 6.
Slinger ring 23 is sized to extend in overlapping relation with aperture 14 of liquid drip pan 13 and is held in substantially parallel preselected spaced relation therefrom by the stop ring 28 which is abutted by collar member 26. Slinger ring 23 is provided with a downwardly extending annular peripheral lip or weir 29 extending downwardly therefrom in spaced, overlapping opposed relation with upwardly extending lip 16 on drip pan 13. Advantageously and in accordance with this invention, it has been found desirable that the spacing between opposed side faces of lip member 16 and 29 and the spacing between the opposed edge face of downwardly extending lip 29 and the upper face of the overlapped drip pan 13 each be equal to or less than approximately 0.187 inches so that the meniscus liquid leakage through the drip pan aperture 14 is prevented.
In operation, any liquid leakage from a sump above the motor is caught by liquid drip pan 13 and flows or is slung outwardly by slinger ring 23 to abut against side wall 17, the liquid passing through side wall openings 18 into outwardly extending drain troughs 19 to fall from drain lips 21 harmlessly away from the motor parts. As above noted, the preselectively spaced, overlapping lips 29 and 16 of the slinger ring 23 and drip pan 13 respectively serve to prevent any meniscus leakage through aperture 14 into the several motor parts.
Thus, from the abovedescribed structure, it can be seen that various advantageous features including those abovenoted are achieved in a comparatively simple, compact, straightforward, inexpensive and efficient manner and that various changes can be made by one skilled in the art in the several parts of the structure without departing from the scope or spirit of this invention. For example, the liquid drip pan could be mounted at a slight angle to gravity favor one drain trough over the other, the slinger shape and lip shapes could be varied in design and contour and the materials utilized could be changed. | An improved drain structure for a vertically mounted electric motor to be positioned below a liquid sump into which the rotor shaft of the motor can be connected including a drip pan through which the rotor shaft passes, the pan having peripheral side walls and drain means attached thereto and a liquid slinger above the pan adapted to sling liquid leakage in a radially outward direction below the pan side walls to be drained away from the motor. | 7 |
TECHNICAL FIELD
[0001] The present invention provides a method and system of controlling an electronic brake system for a vehicle. The method includes estimation of the caliper pressure and comparing the estimated pressure to the commanded pressure. The method eliminates the need for downstream caliper pressure sensors and corresponding control methods of the brake system.
BACKGROUND OF THE INVENTION
[0002] Heretofore, downstream caliper pressure sensors have been required in electronically controlled vehicle braking systems, such as the brake-by-wire type system defined in U.S. Pat. No. 5,558,409 entitled “Electrohydraulic Braking System”, for use in comparing sensed actual caliper pressure feedback from a downstream caliper pressure sensor to commanded or required brake pressure, with any error between the two being accommodated for by varying the position of solenoid operated apply and release valves of the caliper actuation system. These systems typically requires a set of pressure sensors, each one of which is associated with a single wheel brake assembly.
[0003] As will be described in greater detail hereinbelow, the method of the present invention eliminates the need for the downstream caliper pressure sensors and associated control thereof, and also shortens error accommodation response time, allowing larger valve commands in transitions, which results in faster response time for the system, thus enhancing braking capability of the system.
SUMMARY OF THE INVENTION
[0004] According to the invention there is provided a method and system for use in an electronic processor controlled vehicular braking system. The method allows elimination of caliper pressure sensors and any controls systems and associated algorithms from the braking system, while improving braking capability through decreasing response time of the system.
[0005] In the brake-by-wire system, like that used with the present invention, it will be understood that a pump applies high-pressure fluid to an accumulator. The accumulator stores a large volume of high-pressure fluid. The accumulator is used so that high-pressure fluid is always available on demand. Without the accumulator, the system would have to wait until the pump generates pressure before the pressure can be used to activate the caliper. A reservoir is used to hold fluid, which can be sent to the low-pressure side of the pump and also collects fluid from a release valve. Brake calipers convert the fluid pressure to force, which is applied to brake rotors. As fluid enters the calipers the caliper pistons are displaced. The amount of fluid to achieve desired pressure is a function of the caliper compliance.
[0006] With respect to operation of a brake-by-wire system, it should be understood that three important forces are acting on each valve, also known as a proportional poppet valve. The three forces include a force applied by an electrical coil, a force applied by fluid pressure and a biasing force applied by a spring in the valve. When a current is applied to the coil, the poppet is moved in such a way to permit fluid to flow between the accumulator to the caliper. As the fluid pressure increases in the caliper, the pressure difference across the valve reduces and therefore the fluid pressure force reduces. Thus, when the coil force and the spring force remain unchanged the valve begins to close. The proportional poppet valve will close completely when the differential pressure across the valve is reduced and the spring force overcomes the coil and any remaining fluid pressure force. Therefore, a given coil current results in a given caliper pressure.
[0007] Because the object of the present invention is to eliminate the need for caliper pressure sensors, fluid pressure at the caliper is estimated. To estimate the pressure at the caliper, fluid flow through the valve is determined. For a given coil and pressure force the valve will move to a particular position. If the pressure force is reduced or increased the valve will move accordingly and the gap in the valve or opening therethrough will change. If the coil forces increase or decrease the gap will also change accordingly. The gap in the valve determines the fluid flow through the valve. Therefore, for a given current to the coil and a given differential pressure across the valve there will be a given flow through the valve, which can be determined experimentally on a flow bench.
[0008] With knowledge of the caliper compliance (determined experimentally) and the fluid flow through the valve, pressure inside the caliper can be estimated. Pressure inside the caliper is a function of the volume of the fluid inside the caliper. The volume of incoming fluid can be determined by integrating the flow through the apply valve. The volume of the fluid leaving the caliper is determined by integrating the flow through the release valve. The volume of fluid in the caliper is known and therefore the caliper pressure is known. With this information, the pressure at the caliper can be estimated, and control of the valves can occur without a pressure sensor located at each caliper.
[0009] One aspect of the present invention provides a method of controlling a brake system including eliciting a command pressure value from a brake processor or control module of the system; initializing and generating an estimation of caliper pressure through use of empirically determined system specific data in control module memory, comparing the command pressure value to the estimated pressure value and, if a correlation error exists, calculating opening and closing parameters for apply and release valves for caliper actuation medium to eliminate the error; and cycling back through at least the above steps in closed loop fashion until the comparison of command and estimated pressures provides a substantially no error reading, indicating a steady state between the estimated and required or command caliper pressure.
[0010] Through use of a second method of the set, estimated caliper pressure for each cycle is determined, and through use of a third method of the set, the apply and release valves are constantly manipulated about a steady state position for increasing reactivity thereof, and eliminating any steady state error that might exist, over time.
[0011] An aspect of the present invention includes a brake control method for use in an electronically controlled brake-by-wire type vehicular braking system including determining a command caliper pressure, determining an estimated caliper pressure, comparing the command to the estimated caliper pressure to produce an error value, multiplying the error value by a predetermined gain to produce a valve command and controlling apply and release valves responsive to the valve command.
[0012] In other aspects of the present invention the determination of the command caliper pressure includes determining a command pressure value from a brake control module of the system, determining a wheel speed, calculating a wheel speed gain value from the sensed wheel speed and proportioning the wheel speed gain value to the command pressure value to provide a proportioned wheel speed gain value, the proportioned wheel speed gain value providing the command caliper pressure.
[0013] In other aspects of the present invention the determination of the estimated caliper pressure includes sensing a supply pressure reading from a high pressure source for the caliper actuating medium, eliciting a past cycle estimated pressure value, comparing the supply pressure with the estimated past cycle pressure value to obtain a differential pressure reading across the caliper and comparing the differential pressure reading, the past cycle pressure value reading, a past value direction reading and a past valve operation command to corresponding lookup tables for apply pressure vs. valve position and release pressure vs. valve position. The lookup table results can be saturated to assure they are within limits of the system. An estimation of caliper pressure can be initiated from the saturated input parameters when a brake pedal of the system is applied and the estimation can be saturated within system limits. In other aspects of the method of the present invention the command pressure can be compared to the saturated estimated pressure and, if an error exists, appropriate opening and closing of the apply and release valves are controlled to eliminate the error and the steps are cycled through in closed loop fashion until the comparison of command and estimated pressures provides a substantially negligible error reading, indicating a steady state.
[0014] The method of the present invention can include name dithering process in the change of command caliper pressure function. The dithering process can be apply to the command caliper pressure when the pressure is at a steady state above a predefined lower limit, such that fluctuations of the dither are applied to the command caliper pressure at steady state to keep apply and release valves of the system constantly operational rather than fixed in position, while still maintaining the steady state.
[0015] The rates of flow, through both apply and release valves, can be determined simultaneously. The rates of flow can be summed through both apply and release valves. The summed flow rates can be converted to a volume reading. The predetermined corresponding pressure value can be compared to the command pressure value to determine if a difference exists. From an existing difference it is determined which of the apply and release valves must be actuated to eliminate the difference. At least one of the apply and release valves are controlled to eliminate the error difference and produce a steady state.
[0016] At least one of the apply and release valves can be oscillated by applying a dither feature to the command pressure value, causing the value to oscillate between upper and lower values between which the steady state is centered.
[0017] Estimation of caliper pressure can further include comparing line in solenoid valve flow to a lookup table of apply pressure values in a memory of a control module of the system, comparing line out solenoid valve flow to a lookup table of release pressure values in a memory of a and control module of the system and summing the pressure values together to obtain estimated caliper pressure. A saturation point restriction based on system limits can be applied to the estimated caliper pressure. All variables can be placed under a saturation point restriction based on system limitations. All variable values can be reset to 0 upon brake pedal release. Command pressure and accumulator pressure can actualize upon logic initialization. Release of the brake pedal can be recognized by the logic; ending the process. The dither feature can be turned off below a predefined command pressure value.
[0018] Another aspect of the present invention in an electronically controlled vehicular braking system incorporating a caliper actuation assembly including at least one valve, provides a method including the steps of generating pressure application command to the caliper actuation assembly by controlling positioning of the at least one valve thereof, estimating the actual pressure applied from a lookup table of predefined levels of applied pressure corresponding to valve position and generating periodic modulated valve control signals until a near zero difference is determined to exist between the command and estimated applied pressures from the predetermined lookup table data correlating estimated applied pressure and valve position.
[0019] Another aspect of the present invention provides an electronically controlled brake system including a controller for controlling pressure applied by a brake caliper through adjustment of at least one valve associated with the caliper, required valve adjustment being determined from a lookup table of estimated pressure applied correlated to valve position, with valve position being adjusted continuously until the estimated pressure applied is substantially identical to pressure required to produce a brake apply of required level as it pertains to brake command pressure.
[0020] Another aspect of the present invention provides a brake control system including means for determining a command caliper pressure, means for determining an estimated caliper pressure, means for comparing the command to the estimated caliper pressure to produce an error value means for multiplying the error value by a predetermined gain to produce a valve command and means for controlling apply and release valves responsive to the valve command.
[0021] The foregoing and other features and advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention rather than limiting, the scope of the invention being defined by the appended claims and equivalents thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] [0022]FIG. 1 is a schematic block diagram generically setting forth the steps of the method of the present invention.
[0023] [0023]FIG. 2 is an enhanced detail block diagram of the caliper pressure-estimating method of the set of FIG. 1.
[0024] [0024]FIG. 3 is an enhanced detail block diagram of the dithering method of the set of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] Referring now to the drawings in greater detail, there is generically illustrated in FIG. 1 an embodiment of a method of the present invention for use in an electronic processor controlled braking system of the type described in U.S. Pat. No. 5,558,409, the teachings of which are incorporated herein by reference.
[0026] The present invention includes a brake control method 1 , which includes three distinct yet interrelated logical operations. A first process or operation 10 includes a main or command control method 10 . A second operation 12 (FIG. 2) includes a caliper pressure-estimating method 12 . And, a third operation 14 (FIGS. 1 and 3) includes a dither or modulating method 14 .
[0027] The brake control method 1 of the present invention is provided as an improvement over the above-mentioned brake system that incorporates use of downstream caliper pressure sensors in braking control, with the present method 1 eliminating the need for such caliper sensors, and any process steps associated therewith. It will be understood that use of the herein described process set 1 is only applicable during braking application, with any input variables resetting to zero upon release of the brake pedal.
[0028] Upon initialization, although it is preferred that variables be initiated from a 0 value, certain parameters can begin at true reading levels for functionality of the system. In this respect, a command pressure value, and actuating fluid supply pressure values will be available at initialization. Also, a brake request will be recognized for initialization of the operation 1 , as will be understood by those skilled in the art upon perusal of the teachings herein.
[0029] Beginning with FIG. 1, the first cyclic operation 10 of the set 1 can begin with the reception of a sensed brake command pressure value 16 , as determined through application of a corresponding process described in the teachings of U.S. Pat. No. 5,558,409 via brake pedal activation sensed at 18 by the driver of the vehicle incorporating the processor controlled electronic brake system. Concurrently, a wheel speed determining process 20 such as that also defined in U.S. Pat. No. 5,558,409, can be performed by the brake control module or processor of the system disclosed therein. Wheel speed 20 can be used to confirm that caliper pressure is correct for the required or commanded level of braking by checking for the required wheel deceleration, with the wheel speed data also defining a wheel speed gain 22 to be used herein. The wheel speed value 20 and the command pressure value 16 , can be fed to a proportional wheel speed gain calculator 22 wherein the gain 22 and command pressure 16 are multiplied together and then multiplied by an empirically predetermined system specific, proportioning factor, with the proportioned output value 24 providing required or command caliper pressure, used in caliper pressure error determination 26 , as will be described below.
[0030] In one embodiment, a dither feature 14 used in eliminating any steady state errors that may exist, over time, may be applied to the command pressure value 24 , as will be described in detail in connection with the description of FIG. 3.
[0031] Next, pressure within a high-pressure accumulator or source for a medium (typically a hydraulic fluid) used for caliper actuation can be sensed at 28 . It will be understood here that the medium from the high-pressure accumulator can be fed to the caliper through a proportional poppet apply valve (shown at A) in a medium-in line as is known in the art. Pressure in the medium-in line is incrementally adjustable based on electrical current applied to the valve, within inherent limits, to provide required caliper 100 pressure for vehicle braking. Likewise, it will be understood that the medium must be drainable, or the pressure generated thereby to be released, to allow for release of the calipers 100 , draining also being controlled through use of a similar incrementally adjustable proportional poppet release valve (shown at R), with the medium draining, for example, to a reservoir at atmospheric pressure.
[0032] The accumulator pressure value 28 together with an estimated caliper pressure value 30 from a previous loop of this cyclic logic can be used to calculate the required differential pressure across the apply and release valves A, R, to develop conformity of estimated applied caliper pressure to the command pressure.
[0033] Such calculation of the differential pressure at 34 can be accomplished in part through use of lookup tables. It will be understood that the lookup tables referred to herein can be separate tables or a combined table including, for example, both apply and release flow rate data and caliper compliance data. It will also be understood that all the lookup tables defined herein incorporate data that has been empirically determined, with values therein necessarily taking into account physical limits of the system. This can be best understood when looking at FIGS. 1 and 2 concurrently.
[0034] A first lookup table can include empirically determined proportional differential pressure values across the apply valve at 33 , with the pressure values being correlated to apply valve position. A second lookup table can include empirically determined proportional differential pressure values across the release valve at 36 , with the pressure values again being correlated to release valve position.
[0035] It will be understood by those skilled in the art that the degree of orifice opening of the valve is changeable relative to the amount of current provided to the coil actuator. Thus, the lookup table values can be deduced with a great degree of accuracy. It will also be understood that all systems have built in limitations. For example, there is a maximum level of flow through a valve orifice that cannot be overcome, as there is a maximum amount of current available in a particular closed circuit. Therefore such limitations can be accommodated by setting upper limits, which can be defined as points of saturation.
[0036] In the embodiment illustrated, the points of saturation are not incorporated into the lookup tables but rather can be applied separately, at 38 for the apply value and at 40 for the release value. Incorporating system limitations into the lookup table definitions can eliminate this separate saturation application. However, if desired to “fine tune” the system at some future date, saturated lookup tables can be completely recreated, which is a more demanding task than setting out saturation determinants separately and simply modifying single values being processed.
[0037] The saturation points are incorporated herein because the process set 1 cyclically loops and considers prior value data and any generated values, which are not feasible for consideration within system limits, should be avoided. For example, if limits of current available for the system were hypothetically 30 amps, taking into account a requirement of 100 amps would be impossible to accommodate, and would skew future cyclic determinations as well. Thus, saturation points for the system can be predefined to prevent such skewing.
[0038] Next, fluid flow through the caliper 100 can be determined from the estimated apply and release values. The apply value, which increases caliper pressure value, can be considered a positive value and the release value, which decreases caliper pressure value, can be considered a negative value. The sum of the estimated apply and release values provides a flow value for the caliper. However, flow is converted to volume because caliper stiffness is determinable from volume change, from which the caliper pressure then may also be deduced.
[0039] Flow is typically defined as volume over time. To obtain a desired volume reading, the flow value can be integrated at 42 , through application of a known formula of 1/s, with s being a system specific parameter, as known. This is known as a “Laplace Transform”. It will be understood that integration calculations should only be made during brake application, with a zero constant being reset at 44 for all variables upon brake pedal release sensed at 18 , to minimize and preferably eliminate potential integration errors. Reiterating, pressure error 26 can be computed as the difference between the estimated and command pressure, with the estimated pressure value also being saturated at 46 .
[0040] Gain scheduling can be again applied at 48 , a further lookup table providing gain values, with such values being “fine tunable” in any desired manner for system specificity. Gain can be based on error; with the error term being proportioned at 52 by multiplication thereof by a system specific gain, to provide a feedback valve command function at 56 A, 56 R. Presentation of gain in lookup table form provides added flexibility to the system by providing error based gain values rather than by application of a constant with the error factor here being multiplied by a gain that is proportional to, or a function of, the gain itself.
[0041] The proportional value can be saturated at 54 and fed out as a valve command at 56 A, 56 R eliciting valve opening or closure, to a particular degree, of a particular valve (A or R, respectively). This logic stream can be repeated cyclically, generating estimated caliper pressure values based on instantaneous valve position as it relates to the valve command 56 A, 56 R.
[0042] The values from a past pressure loop 58 and the current loop can be summed to provide the feedback term which is saturated to system limits and fed back to the apply and release tables to recalculate flow through the caliper 100 relative to the valve command. It will be understood that the apply and release lookup table values 34 and 36 are continuously one loop behind the remaining logic data with respect to feedback thereto.
[0043] Next, the direction for valve activation can be determined. Here, rather than considering the level of opening or closing a valve must be set, a determination can be made as to which valve is to be activated; the apply or release valve. This determination at 60 is based on error and the sign thereof. Here, it will be understood that a 0 pressure error indicates a steady state. Thus, if pressure error is greater than 0, system logic must necessarily activate the apply valve, increasing pressure and if the pressure error. Conversely, if the pressure error is less than 0, the pressure needs to decrease, thereby also decreasing the pressure error. Bringing a steady state into existence here would then require activation of the release valve instead. Viewed in another way, relative to the sign of the error, positive actuates apply while negative actuates release.
[0044] From this point, a desired valve A, R can be actuated in a desired manner to eliminate pressure error, thus to produce the desired actual pressure in the caliper, via issuance of the valve command 56 A or 56 R to the appropriate valve A or R of the system. The valve command 56 A or 56 R will necessarily be within system limits, with a predetermined saturation table for this variable being located in controller memory and the saturation being applied at 54 prior to valve actuation.
[0045] It should be understood that the current through coil of valve A or R controlling valve actuation thereof can be determined by lookup table 55 A or 55 R for the apply and release valves respectively. In each table 55 A, 55 R, the entering pressure value is converted to a current to provide an apply or release command according to direction.
[0046] Feedback data can be fed to and incorporated into the data in corresponding lookup tables for a plurality of variables for use in the next cyclic computations. As shown, these feedback variables comprise past estimated caliper pressure 30 , past error direction 64 , and past valve actuated 16 . Here, the need for setting of the various saturation limits becomes clear.
[0047] The second feature 12 , (See FIG. 2), of the process set dealing with steps taken in determining the estimated caliper pressure for use in the method depicted in FIG. 1 is more fully detailed in FIG. 2. First the known apply differential value as calculated 32 in relation to FIG. 1 and the known command pressure 58 from a previous loop of the cyclic logic can be compared to a predetermined value set of apply rates in an apply rate lookup table in processor memory at 33 . The correlated apply rate value can be then saturated to system limits at 38 . Based on the flow rate value, direction for flow, i.e., in terms of apply or release, can be determined as will be described, with logic being set to 1 for apply and to 0 for release, with the upper stream of the illustration being applicable to the apply calculation for flow through the apply value.
[0048] The lower logic stream of the illustration is, conversely, applicable to release rate calculation for determining flow through the release valve. Here a release rate lookup table 36 , which has empirically predetermined values therein, can be consulted by the logic, this table including calibration variables, to provide a release rate value. This release rate value can be again saturated at 40 to system limits. Thus, the upper logic stream provides apply pressure, and the lower logic stream provides release pressure, with a sum of the two providing differential pressure across the release valve, which correlates to caliper pressure.
[0049] The process can then move onto direction logic to determine which of the apply and release valves are to be activated, logic being set to recognize that if it is not the release valve to be activated, the logic is 0, but if it is the release valve to be activated, the logic is 1. The logic values can be then summed to provide a pressure rate value input to 70 .
[0050] The apply/release logic 70 can employ a NOT logical operation 72 between the apply and release logic streams, which acts to convert the logic 1 to 0 and the logic 0 to a 1, as is known, by multiplying by 1, to reverse the logic.
[0051] It will be remembered that the logic is set to recognize apply as 1 and release as 0. Thus, if the direction provides a 1 for apply, this is multiplied by 1, which becomes 0 after application of the NOT logic which, when multiplied by the release saturated flow, provides a 0. Conversely, the other option of direction 0 for release, becomes 1 after application of the NOT logic, after multiplying by 1. The apply and release logic values are summed to provide a flow or pressure rate value, to provide the estimated caliper pressure for use in the process of FIG. 1.
[0052] Turning now to FIG. 3, the third process 14 of the set 1 shown in FIG. 1, the dither feature is more fully detailed. In considering this feature 14 , it will be remembered that each caliper 100 incorporates an actuating medium-in line and an actuating medium-out line. Logically, the apply valve is positioned within the medium-in line and the release valve is positioned within the medium-out line. Once a steady state is reached by the system, with desired pressure being applied by the caliper, the apply and release valves both close, maintaining the caliper pressure steady state therebetween. If in a steady state, with both valves maintained closed, there would be no means available to reduce any steady state caliper pressure error that may exist.
[0053] The dither feature 14 comprises a process that alternately sums a small positive value and a small negative value onto the command pressure value 16 , to alternately open and close, respectively, the apply and release valves, each over a brief time interval, so that such steady state error is equalized over time. This can be accomplished by generating a saw tooth wave, or the like at 74 , moving back and forth about the steady state value. In this respect, the command pressure can be construed to exist as a step form wave which could, as an example, have a range of 0 to 100 psi, with the saw tooth dither wave 74 having a range of positive to negative 20 psi, as an example, with each complete cycle of the wave being accomplished over an identical period of time which is predefined for the particular system to which it is applicable.
[0054] Summing of the oscillating dither values 74 with the command pressure value 16 at predetermined time intervals will produce a fluctuation of pressure value about a steady state point, as shown at 76 . To maintain the dither range about the steady state point within proportional limits, it is necessary to be able to turn this feature on and off, as necessary.
[0055] In the exemplary embodiment shown, the on/off point might be set at 78 at greater than 100 psi, such that if command pressure is above 100 psi, logic output becomes 1 to turn the feature “on” and if command pressure is below 100 psi, logic output is 0, turning the feature “off”, at 80 .
[0056] The dither feature 14 should be capable of being turned off so that, should the command pressure be 100 psi or less, and the dither feature 14 be set to turn on at 100 psi, with dither range being set at negative to positive 50 , for example, the pressure could drop dramatically, which would be detrimental to appropriate system function. Therefore, it is preferable to be able to turn the feature 14 off when dealing with an insubstantial steady state error and only applying the feature 14 against a significant steady state error to equalize same to the steady state value over time.
[0057] Thus, the dither process 14 can produce slight fluctuations of pressure about the steady state point, keeping the apply and release valves intermittently actuated, to reduce steady state error in the area of the system therebetween, which area incorporates the caliper 100 .
[0058] Through empirical testing of an electronically controlled caliper, activation of which is accomplished through use of the method set of the present invention, it has been shown, not only is caliper reaction time decreased, but also actual caliper pressure is found to correlate extremely well with commanded pressure, without the need for caliper pressure sensors of prior systems.
[0059] As described above, the present inventive method set provides a number of advantages, some of which have been described and others of which are inherent in the invention. Also, modifications may be proposed without departing from the teachings herein. Accordingly, the scope of the invention is only to be limited as necessitated by the accompanying claims. | A method of the present invention is provided for use in an electronic processor controlled vehicular braking system. When integrated into such a braking system, the need for down-stream caliper pressure sensors, and any algorithms associated therewith, is eliminated, the method generating and using estimated caliper pressure, for comparison to command pressure instead of actual caliper pressure, and eliciting far quicker yet accurate response to be estimated caliper pressure in line with command pressure. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to silane-terminated prepolymers and moisture-curing adhesive sealant formulations containing said prepolymers.
STATE OF THE ART
[0002] Silane-terminated prepolymers are obtained by a polymerisation reaction of a known type for forming the main chain onto which are subsequently introduced terminal silane functional groups, themselves substituted by hydrolyzable monofunctional substituents such as alkoxy groups. These silane groups, by reaction with atmospheric humidity in the presence of suitable catalysts, hydrolyze with each other and combine giving rise to the formation of siloxane bonds, allowing the prepolymer to cross-link and to hence pass from the fluid state to the gummy state.
[0003] Various classes of silane-terminated prepolymers are known, i.e.:
[0000] A) Silane-terminated polyesters such as those described in U.S. Pat. No. 4,191,714 and U.S. Pat. No. 4,310,640,
B) Silane-terminated polyurethanes such as those described in U.S. Pat. No. 4,656,816 and U.S. Pat. No. 6,197,912,
C) Silane-terminated prepolymers in which the main chain is polyether which is subsequently reacted with molecules containing silane groups, Si(OR), where R is a hydrolyzable group, principally an alkyl group, such as those described in U.S. Pat. No. 5,051,463, U.S. Pat. No. 4,507,469, U.S. Pat. No. 4,444,974, U.S. Pat. No. 3,971,751 and EP 0844 266 A2.
D) Silane-terminated prepolymers as described in U.S. Pat. No. 6,221,994 and WO03/082958 in the name of the applicant in which the main polymer chain is obtained by Michael polyaddition reaction of an organic derivative containing at least 2 active hydrogens with organic compounds having at least two olefinic unsaturations, activated by the presence of an electronegative group in the alpha position with regard to each of said unsaturations.
[0004] Although the hydrolyzable groups present on the silicon in all four of the aforesaid silane-terminated prepolymer classes can differ in nature, the group of greatest interest is the alkoxy group because of the neutral and volatile nature of the alcohol that forms. However, for commercial products, the only alkoxy group present is methoxy as the hydrolysis reaction of this group is rather rapid. The hydrolysis reaction of this group leads to the formation of large amounts of methanol which is very toxic not least because of its high volatility.
[0005] However, substituting this group with one containing more carbon atoms such as ethoxy causes the cross-linking reaction to slow down considerably, hence resulting in the need to increase the amount of cross-linking catalysts.
[0006] The catalysts used for speeding up cross-linking of the aforesaid prepolymers are usually salts of tin or other very toxic heavy metals which present the further disadvantage of entering into the oxidative degradation cycle of the finished products.
[0007] The need was therefore felt to find silane-terminated prepolymers which would not present the aforesaid drawbacks.
SUMMARY OF THE INVENTION
[0008] The applicant has now unexpectedly discovered silane-terminated prepolymers characterized by presenting on at least one silicon atom at least one hydrolyzable aryloxy type functional group.
[0009] In this respect the applicant has surprisingly found that using these aryloxy-terminated prepolymers in adhesive sealant formulations increases their reactivity, enabling the use of toxic metal salt based catalysts to be avoided or in any case their quantity to be greatly reduced compared with the amount normally used in conventional formulations, yet ensuring brief cross-linking times.
[0010] Moreover, by introducing aryloxy groups the reactivity of ethoxy-silyl terminated prepolymers (or alkoxy groups of higher molecular weight) can be increased thus rendering them useful in formulating adhesive and sealant products, hence avoiding the use of silane-terminated prepolymers containing methoxy groups which release toxic methanol during product application; indeed ethoxy-terminated prepolymers are known to be poorly reactive to atmospheric humidity and the release of very volatile and toxic methanol is an increasingly felt problem in this field.
[0011] Furthermore, the substitution of low molecular weight alkoxy groups (e.g. methoxy) with suitable aryloxy groups in the cross-linking stage also has a lower environmental impact in that the amount of VOC emitted into the atmosphere is considerably reduced during product application.
[0012] The present invention therefore also relates to moisture-curing adhesive sealant formulations containing the aforesaid silane prepolymers.
DETAILED DESCRIPTION OF THE INVENTION
[0013] In the present description “aryloxy” is defined as a possibly substituted phenoxy group, or a possibly substituted phenoxy group onto which at least one other aromatic ring, such as a naphthyloxy, is condensed.
[0014] Preferably the aryloxy groups are chosen from: phenoxy, phenoxy substituted at the o-, and/or m-, and/or p-positions with linear or branched C 1 -C 20 alkyl, alkylaryl (e.g. cumyl), alkoxy, phenyl, phenoxy, substituted phenyl, thioalkyl, nitro, halogen, nitrile, carboxyalkyl, carboxyamide, NH 2 , NHR groups in which R is a linear or branched C 1 -C 5 alkyl or phenyl.
[0015] Even more preferably the aryloxy groups are chosen from: phenoxy, linear or branched p-C1-C12 alkyl phenoxy, phenyl-phenoxy.
[0016] In accordance with particularly preferred embodiments they are chosen from phenoxy, p-t-butyl-phenoxy, p-nonylphenoxy, p-dodecylphenoxy, p-t-amylphenoxy, p-t-octylphenoxy, p-cumylphenoxy, 3,5-xylenoxy, di-sec-butylphenoxy, 2-sec-4-tert-butylphenoxy, 2,4-di-tert-amylphenoxy, ortho-cumyl-octylphenoxy, 3,4-(Methylenedioxy)-phenoxy, 4′-hydroxy-biphenyl-4-carbonitrile, 4-phenoxyphenoxy, polyphenylenoxide phenoxy terminated, 4-phenylphenoxy, 1-naphthoxy, 2-naphthoxy.
[0017] In each case those aryloxy groups able to produce high boiling arylalcohols, and hence low VOC emission, are preferred.
[0018] The aryloxy groups in the silane-terminated prepolymer of the present invention are preferably present in quantities of between 0.5 and 100%, more preferably between 5 and 100 mol % on the total moles of hydrolyzable substitutents present on all silicon atoms of said silane-terminated prepolymer.
[0019] Preferably the organic silicon derivative with which the silane-terminated prepolymers are prepared according to the present invention has the following general formula (1):
[0000]
[0000] with a=0, 1, 2; b=0, 1 and where:
X=aryloxy, halogen, hydroxy, alkoxy, acyloxy, ketoximino, amino, amido and mercapto.
R 1 =linear or branched C 1 -C 20 alkyl
R 2 =divalent substituent chosen from the group consisting of linear or branched C 1 -C 20 alkylene, heterocycloalkylenes, aminoalkylenes, alkylene thioethers, alkylene oxyethers;
Z=substitutent chosen from:
[0000]
[0000] in which R″ represents a monovalent hydrocarbon group or a monovalent group able to form a heterocycloalkyl with the nitrogen atom.
[0020] For preparing the silane-terminated prepolymers in accordance with the present invention organic silicon derivatives can be used in which X is always different from aryloxy.
[0021] Subsequently the silane-terminated prepolymers thus obtained are converted into the silane-terminated prepolymers of the present invention by reaction with the corresponding aryl alcohol.
[0022] Preferably the organic silicon derivatives used in the present invention present the following formulae:
[0000] O═C═N—R 3 —Si(R 4 ) a (OR 5 ) 3-a (1a)
[0000] H 2 N—R 3 —Si(R 4 ) a (OR 5 ) 3-a (1b)
[0000] O[CH 2 —CH]—CH 2 —O—R 3 —Si(R 4 ) a (OR 5 ) 3-a (1c)
[0000] HS—R 3 —Si(R 4 ) a (OR 5 ) 3-a (1d)
[0000] CH 2 ═C(R 6 )—COO—R 3 Si(R 4 ) a (OR 5 ) 3-a , (1e)
[0000] HL-R 3 —Si(R 4 ) a (OR 5 ) 3-a (1f)
[0000] where:
R 3 =divalent alkyl radical containing from 1 to 8 carbon atoms;
[0023] R 4 and R 5 =alkyl radicals containing from 1 to 4 carbon atoms and/or aryl radicals;
[0000] L is a divalent group of a 5- or 6-atom saturated heterocyclic ring containing at least one nitrogen atom;
a=0, 1, 2.
[0024] In the present description “aryl radical” means a possibly substituted phenyl, or a possibly substituted phenyl onto which at least one other aromatic ring such as a naphthyl is condensed.
[0025] Preferably the aryl group is chosen from phenyl, naphthyl possibly substituted at the o-, and/or m-, and/or p-positions with linear or branched C 1 -C 20 alkyl, alkylaryl (e.g. cumyl), alkoxy, phenyl, substituted phenyl, thioalkyl, nitro, halogen, nitrile, carboxyalkyl, carboxyamide, NH 2 , NHR groups in which R is a linear or branched C 1 -C 5 alkyl or phenyl.
[0026] Even more preferably the group is chosen from phenyl, linear or branched p-C 1 -C 12 alky phenyl, p-phenyl-phenyl.
[0027] In accordance with particularly preferred embodiments the group is chosen from p-t-butyl-phenyl, p-nonylphenyl, p-dodecylphenyl, p-t-amylphenyl, p-t-octylphenyl, p-cumylphenyl, 3.5-xylenyl, di-sec-butylphenyl, 2-sec-4-tert-butylphenyl, 2,4-di-tert-amylphenyl, ortho-cumyl-octylphenyl, 3,4-(Methylenedioxy)-phenyl, 4′-biphenyl-4-carbonitrile, 4-phenoxyphenyl, polyphenylenoxide phenyl terminated, 4-phenylphenyl, 1-naphthyl, 2-naphthyl.
[0028] Preferably L is the divalent residue of piperazine.
[0029] In accordance with a particularly preferred embodiment the organic silicon derivatives used for preparing the silane-terminated prepolymers of the present invention are chosen from:
1. (3-mercaptopropyl)trimethoxysilane, 2. (3-mercaptopropyl)dimethoxyphenoxysilane, 3. (3-mercaptopropyl)methoxydiphenoxysilane, 4. (3-mercaptopropyl)triphenoxysilane, 5. (3-mercaptopropyl)dimethoxy-ptbutphenoxysilane 6. (3-mercaptopropyl)methoxy-diptbutphenoxysilane, 7. (3-mercaptopropyl)triptbutphenoxysilane, 8. (3-mercaptopropyl)methyl-dimethoxysilane, 9. (3-mercaptopropyl)methyl-methoxy-phenoxysilane, 10. (3-mercaptopropyl)methyl-diphenoxysilane, 11. (3-mercaptopropyl)methyl-methoxyptbutphenoxysilane, 12. (3-mercaptopropyl)methyl-diptbutphenoxysilane, 13. (3-[meta]acryloxypropyl)trimethoxysilane, 14. (3-[meta]acryloxypropyl)dimethoxyphenoxysilane, 15. (3-[meta]acryloxypropyl)methoxydiphenoxysilane, 16. (3-[meta]acryloxypropyl)triphenoxysilane, 17. (3-[meta]acryloxypropyl)dimethoxy-ptbutphenoxysilane, 18. (3-[meta]acryloxypropyl)methoxy-diptbutphenoxysilane, 19. (3-[meta]acryloxypropyl)triptbutphenoxysilane, 20. (3-acryloxypropyl)trimethoxysilane, 21. (3-acryloxypropyl)dimethoxyphenoxysilane, 22. (3-acryloxypropyl)methoxydiphenoxysilane, 23. (3-acryloxypropyl)tri phenoxysilane, 24. (3-acryloxypropyl)dimethoxy-ptbutphenoxysilane, 25. (3-acryloxypropyl)methoxy-diptbutphenoxysilane, 26. (3-acryloxypropyl)triptbutphenoxysilane, 27. (N-nButyl,3-aminopropyl)trimethoxysilane, 28. (N-nButyl,3-aminopropyl)dimethoxyphenoxysilane, 29. (N-nButyl,3-aminopropyl)methoxydiphenoxysilane, 30. (N-nButyl,3-aminopropyl)triphenoxysilane, 31. (N-nButyl,3-aminopropyl)dimethoxy-ptbutphenoxysilane, 32. (N-nButyl,3-aminopropyl)methoxy-diptbutphenoxysilane, 33. (N-nButyl,3-aminopropyl)triptbutphenoxysilane, 34. (N-Ethyl,3-aminopropyl)trimethoxysilane, 35. (N-Ethyl,3-aminopropyl)dimethoxyphenoxysilane, 36. (N-Ethyl,3-aminopropyl)methoxydiphenoxysilane, 37. (N-Ethyl,3-aminopropyl)triphenoxysilane, 38. (N-Ethyl,3-aminopropyl)dimethoxy-ptbutphenoxysilane, 39. (N-Ethyl,3-aminopropyl)methoxy-diptbutphenoxysilane, 40. (N-Ethyl,3-aminopropyl)triptbutphenoxysilane, 41. (3-glycidoxypropyl)trimethoxysilane, 42. (3-glycidoxypropyl)dimethoxyphenoxysilane, 43. (3-glycidoxypropyl)methoxydiphenoxysilane, 44. (3-glycidoxypropyl)triphenoxysilane, 45. (3-glycidoxypropyl)dimethoxy-ptbutphenoxysilane, 46. (3-glycidoxypropyl)methoxy-diptbutphenoxysilane, 47. (3-glycidoxypropyl) triptbutphenoxysilane, 48. N-[3-(trimethoxysilyl)propyl]piperazine, 49. N-[3-(dimethoxy-phenoxysilyl)propyl]piperazine, 50. N-[3-(methoxy-diphenoxysilyl)propyl]piperazine, 51. N-[3-(triphenoxysilyl)propyl]piperazine, 52. N-[3-(dimethoxy-ptbutphenoxysilyl)propyl]piperazine, 53. N-[3-(methoxy-diptbutphenoxysilyl)propyl]piperazine, 54. N-[3-(triptbutphenoxysilyl)propyl]piperazine, 55. N-[3-(triethoxy-silyl)propyl]piperazine, 56. N-[3-(diethoxy-phenoxysilyl)propyl]piperazine, 57. N-[3-(ethoxy-diphenoxysilyl)propyl]piperazine, 58. N-[3-(diethoxy-ptbutphenoxysilyl)propyl]piperazine, 59. N-[3-(ethoxy-diptbutphenoxysilyl)propyl]piperazine, 60. N-[(triethoxy-silyl)methyl]piperazine, 61. N-[(diethoxy-ptbutphenoxysilyl)methyl]piperazine, 62. N-[(diethoxy-methylsilyl)methyl]piperazine, 63. N-[(ethoxy-methyl-ptbutphenoxysilyl)methyl]piperazine.
[0093] The silane-terminated prepolymers of the present invention are preferably chosen from the previously indicated (A), (B), (C) and (D) classes and are more preferably chosen from class (D), i.e. those described in U.S. Pat. No. 6,221,994 and WO03/082958 in the name of the applicant and incorporated by us as reference in their entirety, in which the main polymer chain is obtained by Michael polyaddition reaction of an organic derivative containing at least 2 active hydrogen atoms with organic compounds having at least two double bonds activated by the presence of an electronegative group in the alpha position with respect to each of said double activated double bonds.
[0094] The structures of the Michael polyaddition linear polymers useful for being silanated in accordance with the present invention, can be prepared for example as shown in scheme (2) and scheme (3).
[0000]
[0000] is any organic compound having two activated double bonds and n is a whole number greater than or equal to 1 and HTH is the organic derivative having at least 2 active hydrogen atoms.
[0095] Further examples of structures of branched Michael polyaddition polymers useful for being silanated according to the present invention, prepared from at least one monomer having more than two activated double bonds and HTH, and characterized by different terminal functional groups on the basis of the ratio between the monomers, can be illustrated (which is not, and cannot be, an attempt at reality) as in scheme (4) and scheme (5), where the HTH compound in the specific example is sulphydric acid
[0000]
[0000]
is any organic compound having two activated double bonds and n is a whole number greater than or equal to 1
[0000]
is any organic compound having three activated double bonds and n is a whole number greater than or equal to 1 and c=3
[0098] Not reported herein, for the obvious difficulties related to graphical representation, are all the branched structures obtainable with monomers having more than two activated double bonds and with combinations of monomers of functionality greater than two with monomers of functionality equal to or greater than two. It is evident, however, that for the purpose of this patent any combination of monomers with different degrees of functionality able to produce a viscous fluid polymer is useful (at any temperature and, accordingly, below its gelling point) having terminal functional groups useful for subsequent silanisation with organic silicon derivatives, preferably with the silanes of formula (I). The average numerical molecular weights of said polymers are pre-chosen on the basis of the ratio between the monomers and are selected on the basis of the nature of the monomers themselves and of the final use to which the polymer is destined. Such values can be between 200 daltons and 60000 daltons.
[0099] In a preferred embodiment of the present invention, the organic compounds useful for Michael polyaddition having at least two activated double bonds are chosen from:
[0000] W′[—C(R 7 )═CH 2 ] 2 (9)
[0000] Q[-W—C(R 7 )═CH 2 ] 2 (9a)
[0000] Q[-W—C(R 7 )═CH 2 ] 3 (9b)
[0000] Q[-W—C(R 7 )═CH 2 ] 4 (9c)
[0000] where:
W′=electron attracting group chosen from the group consisting of:
—SO—, —SO 2 —, —O—, —CO—;
[0100] W=electron attracting group chosen from the group consisting of:
—SO—, —SO 2 —, —O—, —CO—, —O—CO—;
R 7 ═—H or —CH 3 ;
[0101] Q=divalent, trivalent or tetravalent group chosen from hydrocarbon, hetero-hydrocarbon, polyether, polyester radicals that can contain repeating units and hence have variable molecular weights.
[0102] In a particularly preferred embodiment the acrylic and/or methacrylic organic compounds have the general formula:
[0000]
[0000] where m=2, 3, 4; R 7 =H or CH 3 ; R 8 is chosen from the group consisting of: di-, tri- or tetra-valent polyether which essentially consists of chemically combined —OR 9 —units, where R 9 is a divalent alkyl group having from 2 to 4 carbon atoms; di-, tri- or tetra-valent linear or branched aliphatic alkyl radical, preferably from 1 to 50 carbon atoms; di-, tri- or tetra-valent aromatic radical, preferably from 6 to 200 carbon atoms; di-, tri- or tetra-valent linear or branched aryl radical, preferably from 6 to 200 carbon atoms or R is one or more combinations of said polyethers, alkyl radicals, aromatic radicals and aryl radicals.
[0103] Structures of organic compounds having at least two activated alkylene bonds are given below by way of example.
[0000] H 2 C═C(R 7 )—SO 2 —C(R 7 )═CH 2 ,
[0000] H 2 C═C(R 7 )—SO—C(R 7 )═CH 2 ,
[0000] H 2 C═C(R 7 )—O—C(R 7 )═CH 2 ,
[0000] CH 3 CH 2 C[CH 2 O—CO—C(R 7 )═CH 2 ] 3 ,
C[CH 2 O—CO—C(R 7 )═CH 2 ] 4 ,
[0104] O{CH 2 C(C 2 H 5 )(CH 2 O—CO—C(R 7 )═CH 2 ) 2 } 2 ,
[0000] H 2 C═C(R 7 )—CO—O-Ph-C(CH 3 ) 2 -Ph-O—CO—C(R 7 )═CH 2 ,
[0000] H 2 C═C(R 7 )—CO—OCH 2 CH 2 O—CO—C(R 7 )═CH 2 ,
[0000] H 2 C═C(R 7 )—CO—OCH 2 CH(CH 3 )CH 2 O—CO—C(R 7 )═CH 2 ,
[0000] C[CH 2 -[OCH 2 CH(CH 3 )] n OCOC(R 7 )═CH 2 ] 4 ,
[0000] H 2 C═C(R 7 )—CO—O(CH 2 CH 2 O) n —CO—C(R 7 )═CH 2 ,
[0000] H 2 C═C(R 7 )—CO—O[CH 2 CH(CH 3 )O] n —CO—C(R 7 )═CH 2 ,
[0000] CH{CH 2 O[CH 2 CH(CH 3 )O] n —CO—C(R 7 )═CH 2 } 3 ,
[0000] H 2 C═CH—SO 2 —(CH 2 CH 2 O) n —CH 2 CH 2 —SO 2 —CH═CH 2
[0000] H 2 C═C(R 7 )—CO—O—[R—O—CO—R′—CO—O] n —R—O—CO—C(R 7 )═CH 2 ,
[0000] where: R7=H or CH 3 ; R and R′=alkyl or aryl radicals.
[0105] Preferably the organic compounds useful for Michael polyaddition, having at least two activated double bonds, are chosen from: di-, tri- and tetra-acrylates; di-, tri- and tetra-methacrylates; di-, tri- and tetra-vinyl sulfones.
[0106] According to the present invention, the most preferred of the diacrylate and dimethacrylate organic compounds are chosen from the group consisting of: compounds of general formula (11)
[0000]
[0000] where:
R 7 ═H or CH 3 ; R 10 =chosen from the group consisting of —CH 2 —CH(CH 3 )—, —CH 2 —CH 2 —, —CH 2 —CH 2 —CH 2 —CH 2 —; —CH 2 —CH(CH 3 )—CH 2 —; n′=whole number from 1 to 400, preferably from 1 to 200, even more preferably from 1 to 50; compounds of formula:
[0000]
[0000] where n is a whole number from 0 to 10 and R7 is H or CH3.
[0107] Preferred by far of the compounds of formula (II) are the compounds in which R 7 is hydrogen and R10 is chosen from:
[0000] —CH 2 —CH(CH 3 )—, and —CH 2 CH 2 CH 2 CH 2 — i.e. polyisopropylene glycol diacrylates, polybutylene glycol diacrylates.
[0108] Preferred among the organic triacrylates and trimethacrylates are:
[0000]
[0000] where:
R7=H or CH3; n″=whole number from 0 to 400, preferably from 0 to 200 and even more preferably from 0 to 50.
[0109] Preferred among the vinyl sulfonic organic compounds are:
[0000]
[0000] where R 11 is chosen from CH 2 —CH(CH 3 )—, —CH 2 —CH 2 —, —CH 2 —CH 2 —CH 2 —CH 2 —; —CH 2 —CH(CH 3 )—CH 2 —;
n′″=a whole number from 0 to 400, preferably from 0 to 200 and even more preferably from 0 to 50.
[0110] The compound of formula H-T-H is an organic compound having at least 2 active hydrogen atoms.
[0111] It is preferably chosen from:
[0000] sulphydric acid, HS(CH 2 ) n SH, HSPhSH, CH 3 (CH 2 ) 3 NH 2 , H 2 N(Ph)NH 2 , piperazine, H 2 N(CH 2 ) n NH 2 , CH 3 NH(CH 2 ) n NHCH 3 , CH 2 (COOH) 2 .
[0112] Some examples of the preparation of the silane-terminated prepolymers of the present invention are given by way of non-limiting illustration together with cross-linking tests of said prepolymers and compared with those of the formulations containing silane-terminated prepolymers but not containing aryloxy groups.
COMPARATIVE EXAMPLES
Example A
Synthesis of trimethoxy-silyl terminated prepolymer
[0113] The reaction is carried out in a steel reactor of approximately 300 litre capacity equipped with mechanical stirring.
[0114] 2.45 kg of piperazine (28.442 mols) are added to 192.20 kg (46.685 mols) of a polypropylene glycol diacrylate having average numerical molecular weight <Mn>=4117 g/mol (by titration of double bonds with dodecyl mercaptan) under stirring and in the presence of 38.44 kg of dioctylphthalate. The reaction is conducted at 80° C. for 14 hours, that is to say until 1 H-NMR analysis confirms the disappearance of the triplet at 2.84 ppm corresponding to methylene in the alpha position with respect to the piperazine NH groups (total conversion of NH groups). The double bond terminated prepolymer thus obtained, when subjected to analysis of double bond concentration, showed a molecular weight equal to <Mn>=10456 g/mol. Subsequently 9.71 kg (39.09 mols) of N-[3-(trimethoxysilyl)propyl]piperazine are added slowly under agitation, at T=90° C., in a dry nitrogen atmosphere.
[0115] After 9 hours the desired product is obtained as confirmed by 1 H-NMR analysis showing the complete disappearance of the signals corresponding to the acrylic double bonds in the region between 5.6 ppm and 6.5 ppm.
[0116] The prepolymer thus obtained appears as a transparent viscous fluid, reactive towards atmospheric humidity and having a viscosity of 11600 mPas at 23° C.
Example B
Synthesis of triethoxy-silyl terminated prepolymer
[0117] The reaction is undertaken in a 30 litre capacity glass reactor equipped with mechanical agitation.
[0118] 180.93 g of piperazine (2.10 mols) are added to 14.32 kg (3.60 mols) of polypropylene glycol diacrylate having <Mn>=3977 g/mole (by titration of double bonds) under stirring in the presence of 2.86 kg of dioctyl phthalate. The reaction is conducted at 80° C. for 14 hours, that is to say until 1 H-NMR analysis confirms total conversion of piperazine NH groups. Titration of double bonds showed a molecular weight equal to <Mn>=11312.
[0119] 781.8 g (2.69 mols) of N-[3-(triethoxysilyl)propyl]piperazine silane are added to the thus obtained prepolymer at T=90° C., under stirring and in a dry nitrogen atmosphere.
[0120] After 9 hours the desired product is obtained as confirmed by 1 H-NMR analysis showing the complete disappearance of the signals corresponding to the acrylic double bonds in the region between 5.6 ppm and 6.5 ppm.
[0121] The prepolymer thus obtained appears as a transparent viscous fluid, reactive towards atmospheric humidity and having a viscosity of 9400 mPas at 23° C.
Example C
Preparation of trimethoxy-silyl terminated prepolymer formulation
[0122] 100 parts by weight of Michael polyaddition polymer (Example A) are mixed with 100 parts of calcium carbonate (previously dried in a dryer), 10 parts of titanium dioxide, 0.5 parts of an antioxidant, 10 parts of vinyl trimethoxy silane as water scavenger and a polyamide wax in a variable quantity depending on the desired rheological characteristics. Mixing is undertaken in a planet mixer under nitrogen atmosphere, heating the mix at 80° C. for 2 hours. The catalyst DBTL (see Table 3) and 1 part of 3-aminopropyltrimethoxy silane as adhesion promoter are then added. The thixotropic fluid thus obtained is degassed and placed in metal pouches where it remains over time without significant changes in its characteristics.
[0123] When exposed to atmospheric humidity the product forms an elastic non-tacky skin depending on the amount of catalyst added and hardens completely in less than 24 hours depending on the thickness of the material.
[0124] The hardened product possesses the following mechanical properties:
[0000] Shore A hardness=35 Elongation at break>130% and
Modulus at 100%=1.0 Mpa
Example D
Preparation of triethoxy-silyl terminated prepolymer formulation
[0125] 100 parts by weight of Michael polyaddition polymer (Example B) are mixed with 100 parts of calcium carbonate (previously dried in a dryer), 10 parts of titanium dioxide, 0.5 parts of an antioxidant, 10 parts of vinyl triethoxy silane as water scavenger and a polyamide wax in a varying quantity. Mixing is undertaken in a planet mixer under nitrogen atmosphere, heating the mix at 80° C. for 3 hours. The catalyst DBTL (see Table 3) and 1 part of N-(2-aminoethyl)-3-aminopropyltriethoxy silane as adhesion promoter are then added. The thixotropic fluid thus obtained is degassed and placed in metal pouches where it remains over time without significant changes in its characteristics.
[0126] When exposed to atmospheric humidity the product forms an elastic and non-tacky skin depending on the amount of catalyst added and hardens completely in less than 24 hours depending on the thickness of the material.
[0127] The hardened product possesses the following mechanical properties:
[0000] Shore A hardness=25 Elongation at break>150% and
Modulus at 100%=0.8 Mpa
Example 1
Synthesis of dimethoxy/p-tertbutylphenoxy-silyl terminated prepolymer (moles/moles=66/33)
[0128] 1.98 g (0.0054 mols) of N-[3-(dimethoxy-p-tertbutylphenoxy-silyl)propyl]piperazine are added to 33.06 g (0.00257 mols) of the double bond terminated prepolymer obtained as in comparative example A, but having <Mn>=10728 g/mol. The reaction is conducted in a 100 ml three-neck glass flask equipped with mechanical stirrer, at T=100° C. under stirring and under light nitrogen pressure.
[0129] After 9 hours the reaction is terminated as confirmed by 1 H-NMR analysis showing the complete disappearance of the signals corresponding to the acrylic double bonds.
[0130] The prepolymer thus obtained appears as a transparent viscous fluid, reactive towards atmospheric humidity and having viscosity of 15300 mPas at 23° C.
Example 2
Synthesis of methoxy/p-tertbutylphenoxy-silyl terminated prepolymer (moles/moles=50/50)
[0131] A batch of the product obtained in comparative example A (102.01 g) is placed in a 250 ml three-neck glass flask equipped with mechanical agitation and connection to a mechanical vacuum pump. The temperature is brought to 110° C. and 4.35 g of p-tertbutylphenol (the necessary quantity to substitute about 50 molar % of methoxyl groups) are added.
[0132] The reaction is conducted under a dynamic vacuum (1 mbar residual) with vigorous agitation and the methanol released is collected in a liquid nitrogen trap.
[0133] After 8 hours a quantity of methanol equal to the theoretical is collected and the reaction is considered complete.
[0134] The prepolymer thus obtained appears as a transparent viscous fluid, reactive towards atmospheric humidity and having a viscosity of 15100 mPas at 23° C.
Example 3
Synthesis of methoxy/di-p-tertbutylphenoxy-silyl terminated prepolymer (moles/moles=33/66)
[0135] 2.82 g (0.00583 mols) of N-[3-(methoxy-di-p-tertbutylphenoxy-silyl)propyl]piperazine are added to 35.68 g (0.00278 mols) of the double bond terminated prepolymer obtained as in comparative example A, but having <Mn>=10728 g/mole.
[0136] The reaction is conducted in a three-neck 100 ml flask at T=100° C. under a head of nitrogen and with mechanical stirring.
[0137] After 9 hours the reaction is completed as confirmed by 1 H-NMR analysis showing the complete disappearance of the signals corresponding to the acrylic double bonds.
[0138] The polymer thus obtained appears as a transparent viscous fluid, reactive towards atmospheric humidity and having a viscosity of 17800 mPas at 23° C.
Example 4
Synthesis of methoxy/p-tertbutylphenoxy-silyl terminated prepolymer (moles/moles=25/75)
[0139] A batch of the product obtained in comparative example A (140.71 g) is placed in a 250 ml glass flask equipped with mechanical agitation and connection to a mechanical vacuum pump. The temperature is brought to 110° C. and 7.66 g of p-tertbutylphenol (the necessary quantity to substitute about 75 molar % of methoxyl groups) are added.
[0140] The reaction is conducted under a dynamic vacuum (1 mbar residual) with vigorous stirring and the methanol released is collected in a liquid nitrogen trap.
[0141] After 10 hours a quantity of methanol is collected equal to the theoretical, and the reaction is considered complete.
[0142] The polymer thus obtained appears as a transparent viscous fluid reactive towards atmospheric humidity and having a viscosity of 17200 mPas at 23° C.
Example 5
Synthesis of p-tertbutylphenoxy-silyl terminated prepolymer(moles/moles=0/100)
[0143] A batch of the product obtained in comparative example A (28.06 g) is placed in a three-neck 100 ml glass flask equipped with mechanical stirring and connection to a mechanical vacuum pump. The temperature is brought to 110° C. and 2.04 g of p-tertbutylphenol (the necessary quantity to substitute all methoxyl groups) are added.
[0144] The reaction is conducted under a dynamic vacuum (1 mbar residual) with vigorous stirring and the methanol released is collected in a liquid nitrogen trap.
[0145] After 10 hours a quantity of methanol is collected equal to the theoretical, and the reaction is considered complete.
[0146] The polymer thus obtained appears as a transparent viscous fluid reactive towards atmospheric humidity and having a viscosity of 20500 mPas at 23° C.
Example 6
Synthesis of p-tertbutylphenoxy-silyl terminated prepolymer (moles/moles=0/100)
[0147] 3.33 g (0.00554 mols) of N-[3-(Tri p-tertbutylphenoxy-silyl)propyl]piperazine are added to 33.88 g (0.00264 mols) of the double bond terminated prepolymer obtained as in comparative example A, but having <Mn>=10728 g/mole.
[0148] The reaction is conducted in a three-neck 100 ml flask at T=100° C. under nitrogen head and with mechanical stirring. After 9 hours the reaction is complete.
[0149] The polymer thus obtained appears as a transparent viscous fluid, reactive towards atmospheric humidity and having a viscosity of 23000 mPas at 23° C.
Example 7
Synthesis of ethoxy/p-tertbutylphenoxy-silyl terminated prepolymer (40/60)
[0150] A batch of the product obtained in comparative example B (138.7 g) is placed in a three-neck 250 ml glass flask equipped with mechanical stirring and connected to a mechanical vacuum pump. The temperature is brought to 110° C. and 5.56 g of p-tertbutylphenol (the necessary quantity to substitute 60 molar % of ethoxyl groups) are added.
[0151] The reaction is conducted under a dynamic vacuum (1 mbar residual) with vigorous agitation and the ethanol released is collected in a liquid nitrogen trap.
[0152] After 8 hours a quantity of ethanol is collected equal to the theoretical, and the reaction is considered complete.
[0153] The polymer thus obtained appears as a transparent viscous fluid reactive towards atmospheric humidity and having a viscosity of 11300 mPas at 23° C.
Example 8
Synthesis of ethoxy/p-tertbutylphenoxy-silyl terminated prepolymer (25/75)
[0154] A batch of the product obtained in comparative example B (220.67 g) is placed in a three-neck 500 ml glass flask equipped with mechanical agitation and connection to a mechanical vacuum pump. The temperature is brought to 110° C. and 11.06 g of p-tertbutylphenol (the necessary quantity to substitute about 75 molar % of ethoxyl groups) are added.
[0155] The reaction is conducted under a dynamic vacuum (1 mbar residual) with vigorous agitation and the ethanol released is collected in a liquid nitrogen trap.
[0156] After 8 hours a quantity of ethanol is collected equal to the theoretical, and the reaction is considered complete.
[0157] The polymer thus obtained appears as a transparent viscous fluid reactive towards atmospheric humidity and having a viscosity of 12500 mPas at 23° C.
Example 9
Synthesis of ethoxy/p-tertbutylphenoxy-silyl terminated prepolymer (5/95)
[0158] A batch of the product obtained in comparative example B (123.77 g) is placed in a three-neck 250 ml glass flask equipped with mechanical stirring and connection to a mechanical vacuum pump. The temperature is brought to 110° C. and 7.86 g of p-tertbutylphenol (the necessary quantity to substitute about 95 molar % of ethoxyl groups) are added.
[0159] The reaction is conducted under a dynamic vacuum (1 mbar residual) with vigorous stirring and the ethanol released is collected in a liquid nitrogen trap.
[0160] After 9 hours a quantity of ethanol is collected equal to the theoretical, and the reaction is considered complete.
[0161] The polymer thus obtained appears as a transparent viscous fluid reactive towards atmospheric humidity and having a viscosity of 19500 mPas at 23° C.
Example 10
Preparation of methoxy/p-tertbutylphenoxy-silyl terminated prepolymer formulation (moles/moles=25/75)
[0162] 100 parts by weight of Michael polyaddition polymer (Example 4) are mixed with 100 parts of calcium carbonate (previously dried in dryer), 10 parts of titanium dioxide, 0.5 parts of an antioxidant, 10 parts of vinyl trimethoxy silane as water scavenger and a polyamide wax in a variable quantity depending on the desired Theological characteristics. Mixing is undertaken in a planet mixer under nitrogen atmosphere, heating the mix at 80° C. for 2 hours. The catalyst DBTL or DBU (see Table 3) and 1.5 parts of 3-aminopropyltrimethoxy silane as adhesion promoter are then added. The thixotropic fluid thus obtained is degassed and placed in metal pouches where it remains over time without significant changes in its characteristics.
[0163] When exposed to atmospheric humidity the product forms an elastic non-tacky skin depending on the amount of catalyst added and hardens completely in less than 24 hours depending on the thickness of the material.
[0164] The hardened product possesses the following mechanical properties:
[0000] Shore A hardness=35 Elongation at break>150% and
Modulus at 100%=1.2 Mpa
Example 11
Preparation of ethoxy/p-tertbutylphenoxy-silyl terminated prepolymer formulation (5/95)
[0165] 100 parts by weight of Michael polyaddition polymer (Example 9) are mixed with 100 parts of calcium carbonate (previously dried in a dryer), 10 parts of titanium dioxide, 0.5 parts of an antioxidant, 10 parts of vinyl triethoxy silane as water scavenger and a polyamide wax in a varying quantity. Mixing is undertaken in a planet mixer under a nitrogen atmosphere, heating the mix at 80° C. for 3.5 hours. The catalyst DBTL or DBU (see Table 3) and 2 parts of N-(2-aminoethyl)-3-aminopropyltriethoxy silane as adhesion promoter are then added. The thixotropic fluid thus obtained is degassed and placed in metal pouches where it remains over time without significant changes in its characteristics.
[0166] When exposed to atmospheric humidity the product forms an elastic non-tacky skin depending on the amount of catalyst added and hardens completely in less than 24 hours depending on the thickness of the material.
[0167] The hardened product possesses the following mechanical properties:
[0000] Shore A hardness=30 Elongation at break>130% and
Modulus at 100%=1.0 Mpa
Evaluating Reactivity of the Prepolymers
[0168] The following demonstrates how the introduction of aryloxy groups leads to an unexpected increase in prepolymer reactivity to atmospheric humidity and how an increased reactivity corresponds to a greater substitution.
[0169] The prepolymers obtained in examples A and B and in examples 1-9, if conserved in a moisture-free atmosphere, remain stable in the form of viscous fluids without significant variations in viscosity. However, over a time-period that varies depending on their reactivity, they transform into a gummy solid (polymer cross-linking) on exposure to atmospheric humidity as a result of the hydrolysis reaction of the silane groups and subsequent condensation of the silanol groups to form siloxane groups.
[0170] The prepolymers are hereinafter evaluated both in the absence of a hydrolysis/condensation reaction catalyst for the terminal silane groups and with the addition of catalysts known in the art, namely the metal compound dibutyltin dilaurate (DBTL) and the amine catalyst 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in varying proportions.
[0171] An approximately 3.5 g polymer sample is mixed with a suitable quantity of catalyst (Table 1 and Table 2) under nitrogen atmosphere and subsequently placed in a PTFE dish-type sample holder of 34 mm diameter and 5 mm height; the entirety is placed in a temperature controlled chamber at 23° C.±1° C. and relative humidity of 50%±5%.
[0172] The reactivity is evaluated by monitoring the formation of surface skin over time, placing the exposed surface in contact with a polyethylene sheet (table 1 and table 2).
Evaluating Reactivity of the Formulations
[0173] The formulations obtained in examples C and D and examples 10-11 conserved in pouches remain stable in the form of thixotropic fluids without significant variations in viscosity. However, over a time-period that varies depending on the reactivity of the prepolymers of which they are composed, they transform into a gummy solid (polymer cross-linking) by exposure to atmospheric humidity.
[0174] The following demonstrates how the use of prepolymers containing aryloxy groups increases the reactivity of the formulations and how this enables catalyst use to be avoided, or to be used in quantities far lower than standard, yet maintaining rapid hardening rates. This satisfies market requirements, which favour quick-acting products (adhesives sector: tack free time 20-30 minutes) while avoiding the drawbacks of using catalysts in high amounts. The absence, or the reduced quantity, of metal salts leads to a combination of lower toxicity of the formulations themselves, and a considerable improvement in the stability to heat and to ultraviolet rays of the materials obtained, properties much appreciated in the sector.
[0175] Indeed, metal salts such as those of tin catalyse the degradation reaction of oxidation and are very toxic products, highly polluting for the environment.
[0176] The products described in examples 10 and 11 are evaluated both in the absence of the hydrolysis/condensation reaction catalyst for the terminal silane groups and with added catalysts known in the art, namely the metal compound dibutyltin dilaurate (DBTL) and the amine catalyst 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in varying proportions as described in examples 10 and 11.
[0177] Approximately 3.5 g of formulation sample is placed in a PTFE dish-type sample holder of 34 mm diameter and 5 mm height and the entirety is placed in a chamber temperature controlled at 23° C.±1° C. and relative humidity of 50%±5%. The reactivity is evaluated by monitoring the formation of surface skin over time, placing the exposed surface in contact with a polyethylene sheet
[0178] See Table 3.
[0000]
TABLE 1
Time (minutes)
Catalyst
Ex. 6
(%
Ex. A
Ex. 1
Ex. 2
Ex. 3
Ex. 4
Ex. 5
(0/
weight)
(100/0)
(66/33)
(50/50)
(33/66)
(25/75)
(0/100)
100)
0
>720
80
72
65
65
28
20
DBTL
45
35
28
21
18
5
3
0.025
DBTL
25
7
7
3
—
—
—
0.12
DBU
>720
40
32
24
20
5
3
0.05
[0000]
TABLE 2
Time (minutes)
Catalyst
Ex. B
Ex. 7
Ex. 8
Ex. 9
(% weight)
(100/0)
(40/60)
(25/75)
(5/95)
0
>1500
210
150
34
DBTL
>720
60
42
7
0.025
DBTL
480
26
18
4
0.12
DBU
>1500
130
110
65
0.05
DBU
>1500
28
23
10
0.1
[0000]
TABLE 3
Catalyst
(parts by
Time (minutes)
weight))
Ex. C
Ex. 10
Ex. D
Ex. 11
0
6 h
40 min
>10 h
50 min
DBTL
3 h
30
9 h
35
0.025
DBTL
1 h
—
6 h
—
0.3
DBU
6 h
30 min
—
70 min
0.05
DBU
5 h
20 min
8 h
25 min
0.1 | Silane-terminated prepolymers which contain, on at least one silicon atom, at least one hydrolyzable aryloxy type functional group. The use of these prepolymers, containing silyl-aryloxy terminated groups, in adhesive sealant formulations increases their reactivity so enabling the use of metal-based catalysts, which are in most cases toxic and act as oxidation catalysts, to be avoided or their quantity to be reduced compared with the standard quantity used in conventional formulations, yet ensuring considerably shorter cross-linking times than those of formulations based on known silane-terminated prepolymers. | 2 |
FIELD OF THE INVENTION
The present invention relates generally to electronic mail, and specifically to methods and apparatus for visualizing electronic mail.
BACKGROUND OF THE INVENTION
Communication between two or more users employing electronic mail (e-mail) over a public network, such as the “World Wide Web” or a local-area network (LAN) is well known. A piece of e-mail typically includes a short message or piece of text, and, optionally, one or more larger files attached to the e-mail. Frequently, a user sends a copy of an e-mail both to one or more primary recipients (specified in the “To:” field) and to other secondary, or “carbon copy” recipients (specified in the “cc:” field). Recipients of the e-mail typically see a list naming each of the other direct and carbon-copy recipients of the e-mail. A piece of e-mail which is forwarded and cc'd a number of times before reaching a recipient typically includes the entire propagation history of the e-mail, starting from its original sender, unless this history is deliberately deleted by a user at some point in the propagation of the e-mail.
Systems which parse electronic mail in order to differentiate between the different fields are known. U.S. Pat. No. 5,948,058 to Kudoh et al., which is incorporated herein by reference, describes a method and apparatus for cataloging and retrieving e-mail. Header information and a defined class of every e-mail are displayed simultaneously so as to enable a user's e-mails to be categorized more efficiently. Each category may have its own symbol or icon to enable simple visual categorization.
U.S. Pat. No. 5,544,360 to Lewak et al., which is incorporated herein by reference, describes a computer filing system for accessing computer files and data according to user-designated criteria.
SUMMARY OF THE INVENTION
In preferred embodiments of the present invention, an e-mail processing program runs on a user's computer, and processes e-mail header information in pieces of electronic mail received by the user. The program preferably provides an on-screen, graphical display containing information regarding each piece of electronic mail. Typically, the information is indicative of the propagation history of the e-mail, e.g., identifying the sender of the e-mail, one or more of its recipients, and, if appropriate, their locations in a corporate or other hierarchy. The information is preferably displayed in a user-friendly way, enabling the user to quickly ascertain geographical, hierarchical, or other information pertinent to any of the correspondents who sent or received any portion of the e-mail.
An advantage, therefore, of some aspects of the present invention, is the ability to provide apparatus and methods for improving the organization of electronic mail data.
A further advantage of some aspects of the present invention is the ability to provide improved apparatus and methods for displaying electronic mail data.
In a preferred embodiment of the present invention, the user's computer provides a graphical display of the organizational hierarchy (e.g., a tree), and superimposes on the hierarchy a series of markers indicative of the propagation history of the e-mail. This display typically enables the user to understand the relative importance of the senders and recipients at each stage in the e-mail's propagation. Thus, for example, the user would be able to quickly see that a given piece of e-mail was sent back and forth among several junior engineers in a particular office, then bounced to a senior engineer, who immediately forwarded it to the CEO, who, in turn, forwarded the mail with added comments to all division chiefs, one of whom ultimately sent the e-mail with no further comment to the user.
By contrast to these embodiments of the present invention, prior art e-mail systems typically display an e-mail in reverse chronological order, with the most recent correspondence displayed at the top. The current state-of-the-art in electronic mail display does not normally enable the user to assess what position in an established hierarchy is held by any of the senders, primary recipients, or secondary recipients. Similarly, the prior art does not readily enable a user to determine what level of authority is attached to any particular part of the e-mail. In summary, knowledge about organizational structure is typically unavailable to prior art e-mail systems, so no such automated analysis of the header information is possible. An attempt to extract this information manually, e.g., by reading the e-mail note and continually referring to an organizational chart, would typically be a long and tedious task.
In a preferred embodiment, the user's computer is enabled to incorporate in the displayed hierarchy a marker indicating a person mentioned in the e-mail who is not necessarily included in the transmission chain of the e-mail. Thus, for example, the user may right-click on the name of a person in the middle of a paragraph in the e-mail, and the computer will mark that name in red on the hierarchy displayed on the user's screen.
It will be appreciated that, by way of illustration and not limitation, the propagation history is generally described herein for display with respect to an organizational hierarchy. Alternatively or additionally, the history may be displayed with respect to other data available to the user's computer, such as, for example, telephone area codes, a map, or the name of each recipient's employer. Further alternatively or additionally, the information may be displayed without any prior knowledge of relationships among the senders and recipients. In this case, each name is preferably displayed at an arbitrarily-selected location on the user's screen, and arrows or other markers are used to show the propagation of the e-mail.
There is therefore provided, in accordance with a preferred embodiment of the present invention, a method for providing information regarding a piece of electronic mail (e-mail), including:
processing a data set containing transmission data associated with the e-mail so as to determine one or more steps in a propagation history of the e-mail, the transmission data including identifiers of a sender of the e-mail and of one or more recipients of at least a portion of the e-mail; and
displaying the propagation history.
Preferably, processing the data set includes analyzing transmission information embedded in text of the e-mail. Alternatively or additionally, processing the data set includes analyzing transmission information not contained in text of the e-mail.
In a preferred embodiment, displaying the propagation history includes designating a first visual symbol to represent transmission of the e-mail to a primary recipient, and designating a second visual symbol different from the first visual symbol to represent transmission of the e-mail to a secondary recipient.
Alternatively or additionally, displaying the propagation history includes designating a first visual symbol to represent the sender and designating at least one visual symbol different from the first visual symbol to represent the one or more recipients. For example, displaying the propagation history may include designating a first color for the first visual symbol and designating a second color, different from the first color, for the at least one visual symbol.
For some applications, displaying the propagation history includes graphically displaying the propagation history, e.g., graphically displaying the steps in the history in an animation mode.
Typically, graphically displaying the propagation history includes:
displaying a representation of the sender and at least one of the recipients; and
displaying a graphical representation of movement of the e-mail from the sender to the at least one of the recipients.
For example, displaying the graphical representation of movement may include displaying an arrow.
In accordance with a preferred embodiment of the present invention, processing the data set includes determining two or more steps in the propagation history of the e-mail, the transmission data including for each step in the propagation history identifiers of a sender and one or more recipients of a respective portion of the piece of e-mail, and the method includes:
receiving from a user a designation of an electronic mail correspondent;
finding at least one identifier in the transmission data corresponding to the designated correspondent; and
displaying part of the piece of e-mail responsive to finding the at least one identifier.
Displaying part of the piece of e-mail may include, for example, displaying e-mail content sent by the correspondent. Alternatively or additionally, displaying part of the piece of e-mail may include displaying e-mail content sent to the correspondent.
In a preferred application, the method includes:
determining a location of the correspondent in a hierarchy;
displaying the hierarchy; and
identifying for the user the location of the correspondent in the hierarchy.
Preferably, the method includes receiving information regarding a relationship relating members in a set, which set includes at least some of: the sender and the one or more recipients, wherein displaying the propagation history includes displaying the propagation history responsive to the relationship. For example, receiving the information may include receiving geographical and/or hierarchical information about the members. Receiving hierarchical information typically includes receiving for each one of a plurality of the members, information indicating: (a) who reports to that member and (b) to whom does that member report.
Displaying the propagation history typically includes:
displaying a hierarchy including the members in the set; and
displaying the propagation history with respect to the hierarchy.
In a preferred embodiment, displaying the propagation history with respect to the hierarchy includes superimposing a representation of the propagation history on the hierarchy.
There is also provided, in accordance with a preferred embodiment of the present invention, a method for providing information regarding a piece of electronic mail (e-mail), including:
scanning the e-mail so as to identify a sender or recipient of at least a portion of the e-mail;
displaying a hierarchy; and
indicating on the hierarchy a location of the sender or recipient in the hierarchy.
There is further provided, in accordance with a preferred embodiment of the present invention, apparatus for providing information regarding a piece of electronic mail (e-mail), including:
a processor, configured to process a data set containing transmission data associated with the e-mail so as to determine one or more steps in a propagation history of the e-mail, the transmission data including identifiers of a sender of the e-mail and of one or more recipients of at least a portion of the e-mail; and
a display, configured to display the propagation history.
There is still further provided, in accordance with a preferred embodiment of the present invention, apparatus for providing information regarding a piece of electronic mail (e-mail), including:
a display; and
a processor, configured to scan the e-mail so as to identify a sender or recipient of at least a portion of the e-mail, configured to drive the display to display a hierarchy, and configured to drive the display to indicate on the hierarchy a location of the sender or recipient therein.
There is yet further provided, in accordance with a preferred embodiment of the present invention, a computer program product for providing information regarding a piece of electronic mail (e-mail), the product including a computer-readable medium having program instructions embodied therein, which instructions, when read by a computer, cause the computer to:
process a data set containing transmission data associated with the e-mail so as to determine one or more steps in a propagation history of the e-mail, the transmission data including identifiers of a sender of the e-mail and of one or more recipients of at least a portion of the e-mail; and
display the propagation history.
There is additionally provided, in accordance with a preferred embodiment of the present invention, a computer program product for providing information regarding a piece of electronic mail (e-mail), the product including a computer-readable medium having program instructions embodied therein, which instructions, when read by a computer, cause the computer to:
scan the e-mail so as to identify a sender or recipient of at least a portion of the e-mail;
display a hierarchy; and
indicate on the hierarchy a location of the sender or recipient in the hierarchy.
The present invention will be more fully understood from the following detailed description of the preferred embodiments thereof, taken together with the drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified pictorial illustration showing a system for visualization of e-mail data, in accordance with a preferred embodiment of the present invention;
FIG. 2 is a flow chart showing a method for matching e-mail data with organizational data, in accordance with a preferred embodiment of the present invention;
FIGS. 3A , 3 B, and 3 C are charts showing the propagation of e-mail through an organization, generated in accordance with a preferred embodiment of the present invention; and
FIG. 4 is a schematic illustration of a computer screen displaying e-mail propagation data in conjunction with an organizational chart, in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 is a simplified pictorial illustration showing a system 20 for visualization of the propagation of e-mail data, in accordance with a preferred embodiment of the present invention. In a typical application, a user of a first computer 54 is enabled to see the one or more steps in the propagation history of a piece of e-mail which was sent over an electronic network 52 , and read, edited, forwarded, and/or “carbon-copied” (cc'd) by users of one or more other computers 54 coupled to the network. Typically, the propagation history is extracted by the user's computer, at least in part, from header information embedded in the body of the e-mail.
The various components of system 20 are preferably constructed generally in accordance with standards known in the art, comprising hardware such as a processor 46 , a data port 48 , a monitor 42 , and a memory 50 , which are configured to allow the processing of electronic mail. Electronic network 52 typically comprises the Internet, but may, alternatively or additionally, include other electronic networks known in the art.
FIG. 2 is a simplified flowchart 60 showing a method for matching e-mail data with organizational data, in accordance with a preferred embodiment of the present invention. In a scan step 70 , computer 54 preferably scans a received e-mail for transmission data, and subsequently analyzes the transmission data to determine address data in an analyze step 80 . In a determine step 90 , computer 54 preferably determines the identities of the various senders and recipients based on the address data. For example, the received e-mail may include the following text:
From: ‘Sharon’ To: ‘Doug’ cc: ‘Michael’, ‘Marilyn’, ‘Lynne’, tim@littleserver.com’ Date: Tuesday, Nov. 10, 1998 11:22 AM Subject: RE: RE: 1998 sales report Okay, everybody. Doug responded by e-mail, and everyone else called me. Let's meet on Friday morning at 8:20. --Sharon >-----Original Message----- >From: ‘Doug’ >Sent: Monday, Nov. 09, 1998 11:08 AM >To: ‘Sharon’, ‘Michael’ >Subject: Re: 1998 sales report >I think it's a good idea. Michael?? Any ideas? >Regards, --Doug >-----Original Message---- >From: ‘Sharon’ >To: ‘Doug’ >cc: ‘Marilyn’, ‘Lynne’, ‘tim@littleserver.com’ >Date: Sunday, Nov. 08, 1998 4:11 PM >Subject: 1998 sales report >Who thinks we should meet to discuss the upcoming report? >--Sharon
In this example, computer 54 scans the address data in the e-mail above and determines that, in the first phase of the e-mail's propagation, ‘Sharon’ is a sender, ‘Doug’ is a primary recipient, and ‘Marilyn,’ ‘Lynne,’ and ‘tim@littleserver.com’ are secondary recipients. Continued analysis preferably generates the entire propagation history of the e-mail. Computer 54 (or another computer) then searches in an organizational chart for the aforementioned names, and, if matches are found, the computer displays the chart with appropriate visual symbols, typically indicating sender, primary recipients, and secondary recipients, in a display step 110 . As appropriate, the visual symbols may be distinguished by color, size, font, style, and/or the use of graphical objects, such as arrows, in order to more clearly indicate the propagation of the piece of e-mail. If some of the names are not found in the organizational chart, then they may be displayed with a symbol or color indicating “no further information known.” Optionally, people on the chart with whom the user has previously corresponded may be marked in a particular color.
In a preferred embodiment, computer 54 displays an animation sequence in step 110 , in which appropriately colored arrows or other markers are superimposed on the chart, so as to represent the movement of the e-mail. Typically, the hierarchical chart is generated based on a representation of the organization's structure, e.g., Beth, John, and Mary report to Steven, Steven reports to Andre, and Andre reports to Charles, the head of the organization.
FIG. 3A is a sample chart 120 showing members of a company, the chart being configured for display on monitor 42 of computer 54 , in accordance with a preferred embodiment of the present invention. Although chart 120 is shown in the figure as displaying an organizational hierarchy, it will be appreciated that other themes (e.g., a map) may be appropriate for other applications. In sample chart 120 , a plurality of hierarchical trees 130 , 140 , 150 , 160 , and 170 , are shown, each representing the authority of employees of the company in five of its offices. As described hereinabove, chart 120 may be obtained from an already existing database, or, alternatively, generated by computer 54 based on analysis of a company telephone directory, payroll register, or other list of employees which includes information relevant to the user. Preferably, computer 54 is enabled to display chart 120 in a variety of different formats (e.g., Tree View, Directory View, Fish-Eye). Alternatively or additionally, the names are shown in a non-hierarchical fashion, e.g., in clusters of names, each cluster having a particular characteristic such as employer, salary range, or nationality. For some applications, the names are displayed on monitor 42 without being arranged with respect to an external organizing characteristic.
FIG. 3B shows chart 120 , and, superimposed thereon, the first stage of propagation of a piece of e-mail, in accordance with a preferred embodiment of the present invention. In this example, arrows 180 , 182 and 184 represent the sending of an e-mail from a sender (Paul Earnest) to three respective recipients (Peter Lawrence, Steve Goddard, and Golan Duvnov). Preferably, arrows leading to primary recipients of the e-mail (i.e., Peter Lawrence) are unbroken, while arrows leading to secondary recipients are dashed. Alternatively or additionally, the names of senders and recipients are highlighted in another suitable fashion, so as to enable the user to easily identify the flow of the e-mail on a large organizational chart. For example, the sender may be marked with a red square, and each receiver may be marked with a blue square.
Advantageously, by displaying senders and recipients in a manner which indicates their ranks within the organization, the user can quickly assess the importance of any name appearing in an e-mail. Thus, in the example shown in FIG. 3B , the fact that the e-mail was sent to no recipient with a rank higher than that of middle-level manager Peter Lawrence might be of great importance to the user. By contrast, prior art e-mail displays, which show a linear and sometimes very long “cc” list, typically make it extremely difficult for the recipient of an e-mail to quickly grasp the ranks and/or office locations of individuals within the company who have read the e-mail.
FIG. 3C shows chart 120 , and, superimposed thereon, the second stage of propagation of the piece of e-mail whose first stage of propagation is shown in FIG. 3B , in accordance with a preferred embodiment of the present invention. In this second stage of the e-mail, arrows 190 , 192 and 194 represent the sending of the e-mail from Peter Lawrence (shown as a recipient in FIG. 3B ), to a primary recipient (Riki Fontaine) and to two secondary recipients (Yaki Goldberg and Nir Ben-Zvi).
FIG. 4 is a sample display showing an output of computer 54 in response to processing a received e-mail, in accordance with a preferred embodiment of the present invention. Preferably, a graphical user interface (GUI) operating on computer 54 receives a mouse input from the user indicating one of the names on a displayed hierarchy, and computer 54 graphically and textually displays the interactions of that person with the received e-mail. For example, if the user clicks on “Gail” in the hierarchy, then computer 54 preferably highlights boxes on the left side of the screen indicating phases in the e-mail's history in which Gail played a role as sender or recipient. Moreover, the text of each of these phases is preferably highlighted in a text-display box at the bottom of the screen.
Alternatively or additionally, the user is enabled to scroll through the text of the e-mail displayed in the text-display box, and propagating arrows on the chart are displayed and updated in accordance with the sender and recipients of any given displayed portion of the e-mail.
Further alternatively or additionally, system 20 provides information to the user concerning a person mentioned in the text of the e-mail itself, but who happens not to be a sender or recipient at any phase in the e-mail's history. Thus, for example, the user may click on the name “Elizabeth Rose” in the middle of a sentence in the e-mail, and computer 54 highlights that name on the organizational chart.
Preferably, some or all of the features described herein with respect to system 20 are incorporated in plug-ins designed to operate with existing electronic mail software, such as, by way of illustration and not limitation, Lotus Notes, Microsoft Outlook, cc:Mail, Commtouch, ProntoMail, Yahoo! Mail, or Eudora. Alternatively or additionally, dedicated stand-alone e-mail software operating on one or more computers in system 20 performs some or all of the processing and displaying functions described herein.
It will be understood by one skilled in the art that aspects of the present invention described hereinabove can be embodied in a computer running software, and that the software can be supplied and stored in tangible media, e.g., hard disks, floppy disks or compact disks, or in intangible media, e.g., in an electronic memory, or on a network such as the Internet.
It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof that are not in the prior art, which would occur to persons skilled in the art upon reading the foregoing description. | A method is described for providing information regarding a piece of electronic mail (e-mail). The method includes processing a data set containing transmission data associated with the e-mail so as to determine one or more steps in a propagation history of the e-mail. The transmission data typically include identifiers of a sender of the e-mail and of one or more recipients of at least a portion of the e-mail. The method also includes displaying the propagation history. Preferably, processing the data set includes analyzing transmission information embedded in text of the e-mail. | 6 |
TECHNICAL FIELD
[0001] The disclosure relates to the technical field of optical networks, and in particular to an Optical Burst Transport Network (OBTN), a node, a transmission method and a computer storage medium.
BACKGROUND
[0002] An OBTN is an optical transmission technology with a granularity between Optical Circuit Switching (OCS) and Optical Packet Switching (OPS), and its key idea is to make full use of a tremendous bandwidth of an optical fibre and flexibility of electronic control to separate a control channel from a data channel. A full optical switching technology is performed on a data channel by adopting Optical Burst (OB) switching unit-based data frames, and control frames and data frames in a control channel correspond one to one and control frams are also transmitted in the optical domain, but are switched to the electric domain for processing at nodes to implement reception and update of corresponding control information in a continuous reception and transmission manner. It will be understood that there may be more than one data channel and more than one control channel, and a section of Fibre Delay Line (FDL) with a fixed length may be utilized to delay bursts in each data channel in case of output competition of the bursts of multiple data channels; and when data frame and control frame channels simultaneously reach a certain node, or the node has no sufficient time to perform reception and transmission control of data frame according to an indication of a control frame after receiving the control frame, the FDL may be utilized to delay the data channels, delay time being exactly equal to time for processing control frame at each node, so as to compensate for a delay difference between the control channels and the data channels to solve the problem of competition. Therefore, an OBTN may implement dynamic adaptation to and good support for various traffic scenarios, and may improve resource utilization efficiency and network flexibility; and in addition, the advantages of high speed, high capacity and low cost of an optical layer are reserved, and applicability to various topologies such as star/tree/ring network is achieved.
[0003] However, using an FDL in a current OBTN technology may make a loop length reach a certain fixed length and has requirements on use of a delay optical fibre for realizing a specific relationship between a data frame and a control frame in a node, setting of an OB packet into a fixed length and setting of a guard interval into a fixed length, thereby complicating a network design, bringing high cost, making length control complex, inadequately keeping a network stable and making it difficult to construct and regulate the network when the loop length changes.
SUMMARY
[0004] In order to solve the existing technical problem, the embodiment of the disclosure is intended to provide an OBTN, a node, a transmission method and a computer storage medium, which may simplify a network design, solve a problem caused by an FDL, lower construction cost of the OBTN, implement flexible construction of the OBTN without greatly limiting throughput of the network, make full use of the throughput of the network and facilitate increase of an operation rate of the network and improvement of efficiency and throughput of the network.
[0005] In order to achieve the purpose, the technical solutions of the disclosure are implemented as follows.
[0006] In a first aspect, the embodiment of the disclosure provides a transmission method for an OBTN, which may include that:
[0007] a master node measures a network loop length of the OBTN, and calculates a length of a data frame, the number of timeslots in the data frame, a length of the timeslot and a guard interval for the timeslot according to a result of the measurement;
[0008] the master node transmits a test data frame and a test control frame to a slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training;
[0009] the slave node performs frame the synchronization training and the timeslot synchronization training according to the test data frame and the test control frame;
[0010] the master node transmits the data frame and a control frame containing a bandwidth map to the slave node according to a result of the frame synchronization training and a result of the timeslot synchronization training;
[0011] the slave node controls reception and transmission of each timeslot in the data frame according to the bandwidth map, the result of the frame synchronization training and the result of the timeslot synchronization training, and transmits a request for bandwidth to the master node; and
[0012] the master node performs bandwidth allocation calculation according to the request for bandwidth, generates a new bandwidth map and transmits the new bandwidth map to the slave node.
[0013] According to a first possible implementation manner, with reference to the first aspect, the step that the master node measures the network loop length of the OBTN may include that: a loop length of a control channel of the OBTN and a loop length of a data channel of the OBTN are measured,
[0014] wherein the step that the loop length of the data channel of the OBTN is measured may include that: any node in the OBTN transmits an OB packet to the master node via the data channel of the OBTN; the master node measures a first time difference between two successive receptions of the OB packet, and determines the first time difference as the loop length of the data channel of the OBTN; and
[0015] the step that the loop length of the control channel of the OBTN is measured may include that: a second time difference between time when a header of the control frame is transmitted by the master node and time when the header of the control frame is received by the master node is determined as the loop length of the control channel of the OBTN.
[0016] According to a second possible implementation manner, with reference to the first aspect or the first possible implementation manner, the step that the master node transmits the test data frame and the test control frame to the slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training may include that:
[0017] the master node transmits the test data frame and the test control frame to the slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, wherein the test control frame contains information about the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot;
[0018] a time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node is acquired; and
[0019] a time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame is acquired, wherein the time interval may contain the time delay.
[0020] According to a third possible implementation manner, with reference to the second possible implementation manner, the step that the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node is acquired may include that:
[0021] the master node transmits the test data frame and the test control frame, and measures the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node; or
[0022] a difference value between the second time difference and the first time difference is determined as the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node.
[0023] According to a fourth possible implementation manner, with reference to the second possible implementation manner, the step that the slave node performs frame synchronization training and timeslot synchronization training according to the test data frame and the test control frame may include that:
[0024] the slave node determines a time delay between time when a header of the test control frame is received and time when a beginning of a first timeslot in the test data frame is received as a reference time delay between time when the control frame is received by the slave node and time when the data frame is received by the slave node;
[0025] the slave node determines a time position of each timeslot in the data frame according to the number of the timeslots in the data frame, the guard interval for the timeslot and the length of the timeslot contained in the test control frame;
[0026] the slave node determines accurate time at which a timeslot is transmitted by the slave node according to the deviation of time at which a timeslot is transmitted by the slave node measured by another node; and
[0027] the slave node transmits the test data frame according to the length of the data frame, the number of the timeslots in the data frame and the length of the timeslot contained in the test control frame as well as the accurate time at which a timeslot is transmitted.
[0028] In a second aspect, the embodiment of the disclosure further provides a transmission method for an OBTN, which may be applied to a master node and include that:
[0029] the master node measures a network loop length of the OBTN, and calculates a length of a data frame, the number of timeslots in the data frame, a length of the timeslot and a guard interval for the timeslot according to a result of the measurement;
[0030] the master node transmits a test data frame and a test control frame to a slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training;
[0031] the master node transmits the data frame and a control frame containing a bandwidth map to the slave node according to a result of the frame synchronization training and a result of the timeslot synchronization training; and
[0032] the master node performs bandwidth allocation calculation according to a request for bandwidth transmitted by the slave node, generates a new bandwidth map and transmits the new bandwidth map to the slave node.
[0033] According to a first possible implementation manner, with reference to the second aspect, the step that the master node measures the network loop length of the OBTN may include that: a loop length of a control channel of the OBTN and a loop length of a data channel of the OBTN are measured,
[0034] wherein the step that the loop length of the data channel of the OBTN is measured may include that: any node in the OBTN transmits an OB packet to the master node via the data channel of the OBTN; the master node measures a first time difference between two successive receptions of the OB packet, and determines the first time difference as the loop length of the data channel of the OBTN; and
[0035] the step that the loop length of the control channel of the OBTN is measured may include that: a second time difference between time when a header of the control frame is transmitted by the master node and time when the header of the control frame is received by the master node is determined as the loop length of the control channel of the OBTN.
[0036] According to a second possible implementation manner, with reference to the second aspect or the first possible implementation manner, the step that the master node transmits the test data frame and the test control frame to the slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training may include that:
[0037] the master node transmits the test data frame and the test control frame to the slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, wherein the test control frame contains information about the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot;
[0038] a time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node is acquired; and
[0039] a time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame is acquired, wherein the time interval may contain the time delay.
[0040] According to a third possible implementation manner, with reference to the second possible implementation manner, the step that the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node is acquired may include that:
[0041] the master node transmits the test data frame and the test control frame, and measures the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node; or
[0042] a difference value between the second time difference and the first time difference is determined as the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node.
[0043] On the third aspect, the embodiment of the disclosure further provides a transmission method for an OBTN, which may be applied to a slave and include that:
[0044] the slave node performs frame synchronization training and timeslot synchronization training according to a test data frame and test control frame transmitted by a master node, and transmits a result of the frame synchronization training and a result of the timeslot synchronization training to the master node; and
[0045] the slave node controls reception and transmission of each timeslot in a data frame according to a bandwidth map transmitted by the master node as well as the result of the frame synchronization training and the result of the timeslot synchronization training, and transmits a request for bandwidth to the master node.
[0046] According to a first possible implementation manner, with reference to the third aspect, the step that the slave node performs frame synchronization training and timeslot synchronization training according to the test data frame and the test control frame may include that:
[0047] the slave node determines a time delay between time when a header of the test control frame is received and time when a beginning of a first timeslot in the test data frame is received as a reference time delay between time when a control frame is received by the slave node and time when the data frame is received by the slave node;
[0048] the slave node determines a time position of each timeslot in the data frame according to the number of timeslots in the data frame, a guard interval for the timeslot and a length of the timeslot contained in the test control frame;
[0049] the slave node determines accurate time at which a timeslot is transmitted by the slave node according to the deviation of time at which a timeslot is transmitted by the slave node measured by another node; and
[0050] the slave node transmits the test data frame according to the length of the data frame, the number of the timeslots in the data frame, and the length of the timeslot contained in the test control frame as well as the accurate time at which a timeslot is transmitted.
[0051] In a fourth aspect, the embodiment of the disclosure provides a master node, which may include:
[0052] a measurement unit configured to measure a network loop length of an OBTN;
[0053] a calculation unit configured to calculate a length of a data frame, the number of timeslots in the data frame, a length of the timeslot and a guard interval for the timeslot according to a result of the measurement of the measurement unit;
[0054] a first transmitting unit configured to transmit a test data frame and a test control frame to a slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot;
[0055] a first training unit configured to perform frame synchronization training and timeslot synchronization training according to the test data frame and test control frame transmitted by the first transmitting unit;
[0056] wherein the first transmitting unit may be further configured to transmit the data frame and a control frame containing a bandwidth map according to results of the frame synchronization training and the timeslot synchronization training performed by the first training unit;
[0057] a first receiving unit configured to receive a request for bandwidth;
[0058] a generation unit configured to perform bandwidth allocation calculation according to the request for bandwidth, and generate a new bandwidth map; and
[0059] wherein the first transmitting unit may be further configured to transmit the new bandwidth map.
[0060] According to a first possible implementation manner, with reference to the fourth aspect, the measurement unit may be configured to measure a loop length of a control channel of the OBTN and a loop length of a data channel of the OBTN,
[0061] wherein the operation that the measurement unit measures the loop length of the control channel of the OBTN may include that: a first time difference between two successive receptions of an OB packet is measured, and the first time difference is determined as the network loop length of the OBTN, wherein the OB packet may be transmitted from any node in the OBTN to the master node via the data channel of the OBTN; and
[0062] the operation that the measurement unit measures the loop length of the data channel of the OBTN may include that: a second time difference between time when a header of the control frame is transmitted by the master node and time when the header of the control frame is received by the master node is determined as the loop length of the control channel of the OBTN.
[0063] According to a second possible implementation manner, with reference to the fourth aspect or the first possible implementation manner,
[0064] the first transmitting unit may be configured to transmit the test data frame and the test control frame to the slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, wherein the test control frame contains information about the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot; and
[0065] the first training unit may be configured to acquire a time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node, and acquire a time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame, wherein the time interval may contain the time delay.
[0066] According to a third possible implementation manner, with reference to the second possible implementation manner, the first training unit may be configured to measure the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node after the test data frame and the test control frame are transmitted, or, determine a difference value between the second time difference and the first time difference as the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node.
[0067] On the fifth aspect, the embodiment of the disclosure provides a slave node, which may include:
[0068] a second receiving unit configured to receive a test data frame and a test control frame;
[0069] a second training unit configured to perform frame synchronization training and timeslot synchronization training according to the test data frame and test control frame received by the second receiving unit;
[0070] wherein the second receiving unit may be further configured to receive a data frame and a control frame containing a bandwidth map;
[0071] a reception and transmission control unit configured to control reception and transmission of each timeslot in the data frame according to the bandwidth map received by the second receiving unit as well as a result of the frame synchronization training and a result of the timeslot synchronization training;
[0072] a second transmitting unit configured to transmit a request for bandwidth; and
[0073] wherein the second receiving unit may be further configured to receive a new bandwidth map.
[0074] According to a first possible implementation manner, with reference to the fifth aspect, the second training unit may be configured to determine a time delay between time when a header of the test control frame is received and time when a beginning of a first timeslot in the test data frame is received as a reference time delay between time when a control frame is received by the slave node and time when the data frame is received;
[0075] determine a time position of each timeslot in the data frame according to the number of timeslots in the data frame, a guard interval for the timeslot and a length of the timeslot contained in the test control frame;
[0076] determine accurate time at which a timeslot is transmitted by the slave node according to the deviation of time at which a timeslot is transmitted by the slave node measured by another node; and
[0077] transmit the test data frame according to the length of the data frame, the number of the timeslots in the data frame, and the length of the timeslot contained in the test control frame as well as the accurate time at which a timeslot is transmitted.
[0078] In a sixth aspect, the embodiment of the disclosure provides an OBTN, which may include: a master node and at least one slave node;
[0079] the master node may be configured to measure a network loop length of the OBTN, calculate a length of a data frame, the number of timeslots in the data frame, a length of the timeslot and a guard interval for the timeslot according to a result of the measurement, transmit a test data frame and a test control frame to a slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training, the master node may also be configured to transmit the data frame and a control frame containing a bandwidth map to the slave node according to a result of the frame synchronization training and a result of the timeslot synchronization training, and the master node may further be configured to perform bandwidth allocation calculation according to a request for bandwidth, generate a new bandwidth map and transmit the new bandwidth map to the slave node; and
[0080] the slave node may be configured to perform frame synchronization training and timeslot synchronization training according to the test data frame and the test control frame, and may further be configured to control reception and transmission of each timeslot in the data frame according to the bandwidth map, the result of the frame synchronization training and the result of the timeslot synchronization training, and transmit the request for bandwidth to the master node.
[0081] In a seventh aspect, the embodiment of the disclosure further provides a computer storage medium having stored therein computer-executable instructions for executing the transmission method, applied to the master node, for the OBTN in the embodiment of the disclosure.
[0082] In an eighth aspect, the embodiment of the disclosure further provides a computer storage medium having stored therein computer-executable instructions for executing the transmission method, applied to the slave node, for the OBTN in the embodiment of the disclosure.
[0083] The embodiment of the disclosure provides the OBTN, the node, the transmission method and the computer storage medium, and by network loop length detection of the master node and frame synchronization training and timeslot synchronization training over the nodes in the network, the network design may be simplified, construction cost of the OBTN may be lowered, flexible construction of the OBTN may be implemented without greatly limiting the throughput of the network, and increase of the operation rate of the network and improvement of the efficiency and throughput of the network are facilitated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0084] FIG. 1 is a schematic diagram of structure of an OBTN according to an embodiment of the disclosure;
[0085] FIG. 2 is a schematic flowchart of a transmission method for an OBTN according to an embodiment of the disclosure;
[0086] FIG. 3 is a schematic flowchart of frame synchronization training and timeslot synchronization training performed by a master node according to an embodiment of the disclosure;
[0087] FIG. 4 is a schematic flowchart of frame synchronization training and timeslot synchronization training performed by a slave node according to an embodiment of the disclosure;
[0088] FIG. 5 is a schematic diagram of transmission of a data frame in an OBTN according to an embodiment of the disclosure;
[0089] FIG. 6 is a schematic flowchart of another transmission method for an OBTN according to an embodiment of the disclosure;
[0090] FIG. 7 is a schematic flowchart of yet another transmission method for an OBTN according to an embodiment of the disclosure;
[0091] FIG. 8 is a schematic diagram of structure of a master node according to an embodiment of the disclosure;
[0092] FIG. 9 is a schematic diagram of structure of a slave node according to an embodiment of the disclosure;
[0093] FIG. 10 is a schematic diagram of a node device according to an embodiment of the disclosure;
[0094] FIG. 11 is a schematic diagram of another node device according to an embodiment of the disclosure; and
[0095] FIG. 12 is a schematic diagram of structure of an OBTN according to an embodiment of the disclosure.
DETAILED DESCRIPTION
[0096] The technical solutions in the embodiment of the disclosure will be clearly and completely described below with reference to the drawings in the embodiment of the disclosure.
[0097] FIG. 1 shows an application scenario according to an embodiment of the disclosure, wherein in an OBTN with a unidirectional ring topology structure consisting of four nodes A, B, C and D, node A may be set as master node, the remaining nodes B, C and D may be set as slave nodes, the black solid circle schematically represents a fibre loop structure, and dotted arrows in the circle represent a transmission direction of a data channel and a data frame; and dotted arrows outside the circle represent a transmission direction of a control channel and a control frame. In an example, in FIG. 1 , the data channel is configured with two wavelengths λ1 and λ2, the control channel is configured with a wavelength λc. It will be understood that the figure is only adopted to exemplarily describe the technical solution of the embodiment of the disclosure and not intended to be any limitation.
[0098] FIG. 2 is a schematic flowchart of a transmission method for an OBTN according to an embodiment of the disclosure, and as shown in FIG. 2 , the transmission method for the OBTN in the embodiment of the disclosure includes the following steps.
[0099] Step 201 : a master node measures a network loop length of the OBTN, and calculates a length of a data frame, the number of timeslots in the data frame, a length of the timeslot and a guard interval for the timeslot according to a result of the measurement.
[0100] In an example, the step may be performed during initialization of the OBTN, and specifically, the step that the master node measures the network loop length of the OBTN may include that: a loop length of a control channel of the OBTN and a loop length of a data channel of the OBTN are measured.
[0101] The step that the loop length of the data channel of the OBTN is measured may include that:
[0102] a certain node (such as the master node or a slave node) is caused to transmit an OB packet to the master node, and the master node waits for successively receiving the OB packet twice; and
[0103] time t 1 when the OB packet reaches the master node for the first time and time t 2 when the OB packet reaches the master node for the second time are measured respectively, and then the loop length of the data channel is a first time difference t L1 between t 1 and t 2 , i.e. t L1 =t 2 −t 1 .
[0104] Correspondingly, after the loop length of the data channel is obtained, the master node may calculate a length of the timeslot of an OB according to the loop length, and the length of the timeslot of the OB includes: length T of an OB packet and a guard interval T 1 between the OB packets. The loop length t L1 of the data channel is an integral multiple of the length of the timeslot of the OB, i.e. t L1 =(T+T 1 )×N, wherein N represents the integral multiple, that is, the loop length of the OBTN includes totally N timeslots. The data frame also consists of timeslots of multiple OBs. Thus, in the embodiment, a data frame preferably includes timeslots of 10 OBs, and the loop length of the data channel is a length of 4 data frames, that is, N is 40.
[0105] It should be noted that, after the OBTN works normally, the master node is still required to perform detection of the loop length in real time to monitor a change in the network loop length and perform corresponding regulation so as to ensure that the loop length is an integral multiple of the length of the timeslot.
[0106] In particular, the step that the loop length of the control channel is measured may include that:
[0107] the master node transmits a header of a control frame at a certain time t 3 , the control frame is sequentially transmitted through each node in the ring network, and then the master node receives the header of the control frame at time t 4 , and then the loop length of the control channel is a second time difference t L2 between t 4 and t 3 , i.e. t L2 =t 4 −t 3 ; that is, the second time difference between time when the header of the control frame is transmitted by the master node and time when the header of the control frame is received by the master node may be determined as the loop length of the control channel of the OBTN.
[0108] The control channel and the data channel are independent of each other and employ different wavelengths, continuous optical information packets instead of OB packets are transmitted in the control channel, and in the control channel, each of the slave nodes is required to perform optical-electric-optical processing and logical judgment before sequentially transmitting the optical information packets. Therefore, It will be understood that the second time difference will be greater than the first time difference.
[0109] Step 202 : the master node transmits a test data frame and a test control frame to a slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training.
[0110] In such case, the test control frame contains information about the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot, the guard interval for the timeslot and the like.
[0111] In an example, FIG. 3 is a schematic flowchart of frame synchronization training and timeslot synchronization training performed by a master node according to an embodiment of the disclosure, and as shown in FIG. 3 , the step may specifically include:
[0112] Step 2021 : the master node transmits the test data frame and the test control frame to the slave node according to the length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot.
[0113] Specifically, in the present embodiment, a length of the test data frame transmitted from Node A to node B is equal to 10 OB timeslots, and the length of each timeslot is T+T 1 , wherein T 1 is the guard interval for the timeslot and T is the Length of the OB packet; and moreover, when operating normally, the master node may also transmit the data frame in such manner. In such case, a header of the data frame is virtual, and, in particular, may be a beginning of a first timeslot in the data frame.
[0114] Step 2022 : the master node acquires a time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node.
[0115] Optionally, the master node measures the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node after transmitting the test data frame and the test control frame.
[0116] Specifically, the master node may transmit the test control frame, in addition to the test data frame, the master node may measure transmission time periods between transmitting and reception of the two frames respectively, and may obtain a time difference between the two time periods for transmission. For example, the time difference may be a time delay between time when the test control frame is received and time when the test data frame is received after the master node simultaneously transmits the test data frame and test control frame which have the same length. Alternatively, the time difference may be a time difference between: a period from time when the test data frame is transmitted by the master node to time when it is received by the master node, and a period from time when the test control frame is transmitted by the master node to time when it is received by the master node, wherein the length of the test data frame is the same as that of the test control frame, and the test data frame and the test control frame are not transmitted simultaneously.
[0117] Optionally, the master node may also determine a difference value between the second time difference t L2 and the first time difference t L1 , which are obtained in Step 201 , as the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node.
[0118] It should be noted that time for transmission of the test control frame in the OBTN is longer than time for transmission of the test data frame in the OBTN, because operation such as photoelectric conversion processing and logical judgment may be executed in the control channel.
[0119] Step 2023 : the master node may acquire a time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame, wherein the time interval includes the time delay.
[0120] Specifically, the master node may treat the time delay obtained in Step 2022 as a part of the time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame. Moreover, it will be understood the time delay accounts for a great proportion of the time interval.
[0121] In addition, the time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame may further include fragmentary time periods such as action time of optical switching of the nodes in the network and a time duration from starting to completion of transmission of a bandwidth map in the control frame, and then the time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame is completely formed.
[0122] Step 203 : the slave node performs the frame synchronization training and timeslot synchronization training according to the test data frame and the test control frame.
[0123] In an example, the step may also be performed in an initialization process of the OBTN. FIG. 4 is a schematic flowchart of the frame synchronization training and timeslot synchronization training performed by the slave node according to an embodiment of the disclosure, and as shown in FIG. 4 , the step may specifically include the following steps.
[0124] Step 2031 : the slave node determines a time delay between time when a header of the test control frame is received and time when a header (i.e. beginning of a first timeslot in the test data frame) of the test data frame is received, as a reference time delay between time when the control frame is received by the slave node and time when the data frame is received by the slave node.
[0125] In the embodiment, node B may receive the test control frame and the test data frame from the master node, i.e. node A, and determines the time delay between time when the header of the test control frame is received and time when the header of the test data frame is received, as the reference time delay between time when the control frame is received by node B and time when the data frame is received by node B during normal work; and node B forwards the test control frame to the next node C, and keeps a delay between reception and transmission of the control frame at the node at a fixed value.
[0126] Node C may also receive the test control frame forwarded by node B and the test data frame transmitted by node A, and determines a time delay between time when the header of the test control frame is received and time when the header of the test data frame is received, as a reference time delay between time when control frame is received by node C and time when the data frame is received by node C during normal work; and node C forwards the test control frame to the next node D, and keeps a delay between reception and transmission of the control frame at the node at a fixed value.
[0127] All of subsequent nodes may obtain their reference time delays between control frame reception and data frame reception during normal work in the manner adopted for node B or node C, and specific processes will not be elaborated.
[0128] Step 2032 : the slave node determines a time position of each timeslot in the received data frame according to the information about the number of the timeslots in the data frame, the guard interval for the timeslot, the length of the timeslot and the like contained in the test control frame.
[0129] In the embodiment, node B may acquire the guard interval for the timeslot and the length of the timeslot from the test control frame, so that node B may calculate time of arrival of the first timeslot of the data frame according to the time delay of the control frame and the data frame when receiving the header of the control frame under a normal operating situation, and then determine the time position of each timeslot in the data frame to accurately receive each timeslot of the data frame according to the guard interval for the timeslot and the length of the timeslot. It will be understood that all of the subsequent nodes may determine the time position of each timeslot in the data frame according to the guard interval for the timeslot and length of the timeslot in the test control frame, in similar manner adopted for node B, after receiving the header of the control frame, and the process will not be elaborated herein.
[0130] Step 2033 : the slave node determines accurate time at which a timeslot is transmitted by the slave node according to the deviation of time, at which a timeslot is transmitted by the slave node, measured by another node.
[0131] Since there may exist a certain delay during processing in a node when the node transmits a data timeslot, transmitting the timeslot according to time when the timeslot is received by the slave node may produce a deviation with respect to time when the timeslot is transmitted by the master node.
[0132] Specifically, in the embodiment, when node B transmits a burst timeslot of the test data frame to node C, a substantial time position T bin at which a certain timeslot in a certain data frame is transmitted may be different from an ideal time position at which the timeslot is transmitted (a current time position T ain at which the timeslot is transmitted by node A), node C may measure a deviation T ain −T bin of time position at which the timeslot is transmitted by node B and report the deviation to node A, then node A feeds back the deviation T ain −T bin to node B through the control frame, and node B may regulate an accurate time position at which each timeslot of the data frame is transmitted by node B according to the deviation between T bin and T bin such that the node B can transmit the burst timeslot at the accurate time position under the normal operating situation.
[0133] Each of the subsequent nodes may obtain accurate time position at which each timeslot in the data frame is transmitted by the node during normal work in a manner adopted for node B, and the process will not be elaborated herein.
[0134] Step 2034 : the slave node transmits the test data frame according to the length of the data frame, the number of the timeslots in the data frame, and the length of the timeslot contained in the test control frame as well as the accurate time at which a timeslot is transmitted.
[0135] Specifically, by performing Step 2031 to Step 2034 , the slave node may implement data frame synchronization training, and timeslot reception and transmission synchronization training by using the frames transmitted by the master node, and subsequently may normally implement OB-packet-based synchronous timeslot transmission according to results of training.
[0136] Step 204 : the master node transmits the data frame and a control frame containing a bandwidth map to the slave node according to a result of the frame synchronization training and a result of the timeslot synchronization training.
[0137] In an example, the OBTN may work normally after the initialization process of the OBTN, i.e. Step 201 to Step 203 . When the OBTN works normally, the master node may transmit the data frame and the control frame to a downstream node in the OBTN. In the embodiment, the downstream node of master node A is slave node B, and node A transmits the data frame and the control frame to node B. The control frame contains the bandwidth map generated by node A, indicating the slave node to control reception and transmission of the data frame. For example, the bandwidth map may indicate that each node may and/or may not receive a certain or some timeslots in a certain or some wavelengths in the data frame, the slave node may and/or may not write data into a certain or some timeslots in a certain or some wavelengths in the data frame and the like, which timeslots may be received by the slave nodes or into which timeslots may be written by the slave nodes, or information about bandwidths which are allocated to the slave nodes by the master node.
[0138] Step 205 : the slave node controls reception and transmission of each timeslot in the data frame according to the bandwidth map, the result of the frame synchronization training and the result of the timeslot synchronization training, and transmits a request for bandwidth to the master node.
[0139] In an example, after receiving the header of the control frame, the slave node may receive the data frame after the reference time delay from the time when receiving the header of the control frame according to the reference time delay obtained in Step 203 , and may also accurately receive each timeslot of the data frame at the accurate time positions according to the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot which are contained in the test control frame obtained in Step 203 .
[0140] During the reference time delay starting from time when the control frame is received, the slave node may read control information from the control frame, for example, reading the bandwidth map from the control frame, and under the indication of the bandwidth map, determine which timeslots in the data frame will be received by the slave node and into which timeslots, data to be transmitted may be written, thereby implementing control over reception and transmission of the data frame.
[0141] Furthermore, the bandwidth map further indicates information about the bandwidth allocated to the slave node by the master node, so that the slave node may transmit the request for bandwidth, which is based on the current traffic distribution of the slave node, to the master node to request the master node to provide a higher or more proper bandwidth when transmitting the data frame next time or next few times.
[0142] Specifically, FIG. 5 is a schematic diagram of a data frame transmission situation in an OBTN according to an embodiment of the disclosure; and according to the data frame transmission situation shown in FIG. 5 , the number of OB timeslots in the data frame is 10, and in order to facilitate description, only the first 6 timeslots are illustrated for description for node B and node C in FIG. 5 , wherein K represents a sequence number of a frame.
[0143] For node B, timeslots 1, 4 and 6 in a data frame transmitted through a data channel with the wavelength λ1 in the (K+3) th frame are timeslots which are transmitted from node A and will be received by node B; timeslots 2, 3 and 5 in a data frame transmitted through a data channel with the wavelength λ2 in the (K+3) th frame are timeslots which are transmitted from node C, node D and node A respectively and will be received by node B; thus, the bandwidth map generated by the master node A may indicate node B to receive timeslots 1, 4 and 6 in the data frame transmitted through the data channel with the wavelength λ1 and timeslots 2, 3 and 5 in the data frame transmitted through the data channel with the wavelength λ2.
[0144] After the (K+3) th frame is transmitted through node B, a service situation of each timeslot is shown in a distribution on the (K+2) th frame in FIG. 5 . Node B may write the data to be transmitted into the timeslots in the data frame after receiving the data transmitted to node B in the timeslots, and the bandwidth map may also indicate sequence numbers of timeslots into which data may be written by node B; for example, node B fills data to be transmitted to node A into timeslot 1 in the data frame transmitted through the data channel with the wavelength λ1 and timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ2, fills data to be transmitted to node D into timeslots 4 and 6 in the data frame transmitted through the data channel with the wavelength λ1 and fills data to be transmitted to node C into timeslot 3 in the data frame transmitted through the data channel with the wavelength λ2.
[0145] Data frame reception and transmission of node B shows that node A allocates 6 reception and transmission timeslots to node B, and node B may transmit a request for bandwidth based on its own resource to node A to request for a higher or more proper bandwidth or a more proper inter-node pair bandwidth.
[0146] For node C, timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ1 in the (K+2) th frame are timeslots which are transmitted from nodes A and D respectively and will be received by node C. Timeslots 3, 4 and 6 in the data frame transmitted through the data channel with the wavelength λ2 are timeslots which will be received by node C; thus, the bandwidth map generated by the master node A may indicate node C to receive timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ1 and timeslots 3, 4 and 6 in the data frame transmitted through the data channel with the wavelength λ2.
[0147] After the (K+2) th frame is transmitted through node C, a service situation of each timeslot is shown in a distribution on the (K+1) th frame. Node C may write data to be transmitted into the timeslots in the data frame after receiving the data in the timeslots, and the bandwidth map may also indicate sequence numbers of timeslots into which data may be written by node C. For example, node C fills data to be transmitted to node D into timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ1 and timeslot 1 in the data frame transmitted through the data channel with the wavelength λ2, and fills data to be transmitted to node B into timeslot 3 in the data frame transmitted through the data channel with the wavelength λ2.
[0148] Similarly, node C may also transmit a request for bandwidth to node A to request for a higher or more proper bandwidth.
[0149] The process that node D controls reception and transmission of the data frame and transmits a request for bandwidth to the master node is the same as those of node B and node C, and will not be elaborated herein.
[0150] It should be noted that timeslot reusability is higher in the embodiment of the disclosure and a node may transmit data by using a timeslot after the same timeslot is received by the nodes in downstream, so that a transmission rate of the network is increased, and throughput of the network is improved.
[0151] Step 206 : the master node performs bandwidth allocation calculation according to the request for bandwidth, generates a new bandwidth map and transmits the new bandwidth map to the slave node.
[0152] In an example, in the embodiment, after receiving the requests for bandwidth from respective slave nodes, node A may perform wavelength and timeslot allocation for each node to generate the new bandwidth map by virtue of a Dynamic Bandwidth Allocation (DBA) algorithm according to a current state of resources of the whole network and the requests for bandwidth of respective slave nodes.
[0153] The embodiment of the disclosure provides the transmission method for the OBTN, in which, by means of network loop length detection of the master node and frame synchronization and timeslot synchronization training of the nodes in the network, FDL is not required in the nodes in the network, a network design is simplified, construction cost of the OBTN is lowered, flexible construction of the OBTN is implemented without greatly limiting the throughput of the network, increase of an operation rate of the network and improvement of efficiency and throughput of the network are facilitated, and an effective rate of an optical network is fully utilized.
[0154] FIG. 6 is a schematic flowchart of another transmission method for an OBTN according to an embodiment of the disclosure, the method is applied to a master node, and as shown in FIG. 6 , the transmission method for the OBTN in the embodiment of the disclosure includes the following steps.
[0155] Step 301 : the master node measures a network loop length of the OBTN, and calculates a length of a data frame, the number of timeslots in the data frame, a length of the timeslot and a guard interval for the timeslot according to a result of the measurement.
[0156] In an example, the step may be performed during initialization of the OBTN, and specifically, the step that the master node measures the network loop length of the OBTN may include that: a loop length of a control channel of the OBTN and a loop length of a data channel of the OBTN are measured.
[0157] In such case, the step that the loop length of the data channel of the OBTN is measured may include that:
[0158] a certain node (such as the master node and a slave node) is caused to transmit an OB packet to the master node, and the master node waits for successively receiving the OB packet twice; and
[0159] time t 1 when the OB packet reaches the master node for the first time and time t 2 when the OB packet reaches the master node for the second time is measured respectively, and then the loop length of the data channel is a first time difference t L1 between t 1 and t 2 , i.e. t L1 =t 2 −t 1 .
[0160] Correspondingly, after the loop length of the data channel is obtained, the master node may calculate a length of the timeslot of an OB according to the loop length, and the length of the timeslot of the OB includes: a length T of the OB packet and a guard interval T 1 between OB packets. The loop length t L1 of the data channel is an integral multiple of the length of the timeslot of the OB, i.e. t L1 =(T+T 1 )×N, wherein N represents the integral multiple, that is, the loop length of the OBTN includes totally N timeslots. The data frame also consists of timeslots of multiple OBs. Thus, in the embodiment, a data frame preferably includes timeslots of 10 OBs, and the loop length of the data channel is a length of 4 data frames, that is, N is 40.
[0161] It should be noted that the master node is still required to perform loop length detection in real time to monitor a change in the network loop length and perform corresponding regulation to ensure that the loop length is an integral multiple of the length of the timeslot after the OBTN works normally.
[0162] The step that the loop length of the control channel is measured may include the following steps.
[0163] The master node transmits a header of a control frame at a certain time t 3 , and after the control frame is sequentially transmitted through each node in the ring network, the master node receives the header of the control frame at time t 4 , and then the loop length of the control channel is a second time difference t L2 between t 4 and t 3 , i.e. t L2 =t 4 −t 3 ; that is, the second time difference between time when the header of the control frame transmitted by the master node and time when the header of the control frame received by the master node may be determined as the loop length of the control channel of the OBTN.
[0164] Since the control channel and the data channel are independent of each other and use different wavelengths, successive optical information packets, instead of the OB packets, are transmitted via the control channel and optical-electric-optical processing and logical judgment are required before sequential transmission at each slave node in the control channel, it will be understood that the second time difference should be greater than the first time difference.
[0165] Step 302 : the master node transmits a test data frame and a test control frame to a slave node according to the calculated length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training.
[0166] Here, the step that the master node transmits the test data frame and the test control frame to the slave node according to the calculated length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot, for performing frame synchronization training and timeslot synchronization training includes that:
[0167] the master node transmits the test data frame and the test control frame to the slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot, the test control frame contains information about the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot;
[0168] a time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node is acquired; and
[0169] a time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame is acquired, wherein the time delay is contained in the time interval.
[0170] Specifically, the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node is acquired includes that:
[0171] the master node transmits the test data frame and the test control frame, and then measures the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node;
[0172] alternatively, a difference value between the second time difference and the first time difference is determined as the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node.
[0173] Step 303 : the master node transmits the data frame and a control frame containing a bandwidth map to the slave node according to a result of the frame synchronization training and a result of the timeslot synchronization training.
[0174] In an example, when the OBTN works normally, the master node may transmit the data frame and the control frame to a downstream node in the OBTN, and in the embodiment, the downstream node of master node A is slave node B, node A transmits the data frame and the control frame to node B. The control frame contains the bandwidth map which is generated by node A, indicating the slave node to control reception and transmission of the data frame. For example, the bandwidth map may indicate that each node may and/or may not receive a certain or some timeslots in a certain or some wavelengths in the data frame, the slave node may and/or may not write data into a certain or some timeslots in a certain or some wavelengths in the data frame and the like, which timeslots may be received by the slave nodes or into which timeslots may be written by the slave nodes, or information about bandwidths which are allocated to the slave nodes by the master node.
[0175] Step 304 : the master node performs bandwidth allocation calculation according to a request for bandwidth transmitted by the slave node, generates a new bandwidth map and transmits the new bandwidth map to the slave node.
[0176] In an example, in the embodiment, after receiving the requests for bandwidth from respective slave nodes, node A may perform wavelength and timeslot allocation for each node to generate the new bandwidth map by virtue of a DBA algorithm according to a current state of resources of the whole network and requests for bandwidth of respective slave nodes.
[0177] The embodiment of the disclosure further provides a computer storage medium having stored therein computer-executable instructions for executing the transmission method, applied to the master node, for the OBTN in the embodiment of the disclosure.
[0178] FIG. 7 is a schematic flowchart of yet another transmission method for an OBTN according to an embodiment of the disclosure, the method is applied to a slave node, and as shown in FIG. 7 , the transmission method for the OBTN in the embodiment of the disclosure includes the following steps.
[0179] Step 401 : the slave node performs frame synchronization training and timeslot synchronization training according to a test data frame and test control frame transmitted by a master node, and transmits a result of the frame synchronization training and a result of the timeslot synchronization training to the master node.
[0180] In an example, the step that the slave node performs the frame synchronization training and timeslot synchronization training according to the test data frame and the test control frame includes that:
[0181] the slave node determines a time delay between time when a header of the test control frame is received and time when a beginning of a first timeslot in the test data frame is received, as a reference time delay between time when a control frame is received by the slave node and time when the data frame is received by the slave node;
[0182] the slave node determines a time position of each timeslot in the data frame according to the number of timeslots in the data frame, a guard interval for the timeslot and a length of the timeslot which are contained in the test control frame;
[0183] the slave node determines accurate time at which a timeslot is transmitted by the slave node according to the deviation of time, at which a timeslot is transmitted by the slave node, measured by another node; and
[0184] the slave node transmits the test data frame according to the length of the data frame, the number of the timeslots in the data frame and the length of the timeslot contained in the test control frame as well as the accurate time at which a timeslot is transmitted.
[0185] Step 402 : the slave node controls reception and transmission of each timeslot in a data frame according to a bandwidth map transmitted by the master node, the result of the frame synchronization training and the result of the timeslot synchronization training, and transmits a request for bandwidth to the master node.
[0186] In an example, after receiving the header of the control frame, the slave node may receive the data frame after the reference time delay from time when receiving the header of the control frame according to the obtained reference time delay, and may also accurately receive each timeslot of the data frame at the accurate time positions according to the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot which are contained in the test control frame.
[0187] During the reference time delay from time when the control frame is received, the slave node may read control information from the control frame, for example, reading the bandwidth map from the control frame, and under the indication of the bandwidth, determine which timeslots in the data frame will be received by the slave node and into which timeslots, data to be transmitted may be written, thereby implementing control over reception and transmission of the data frame.
[0188] Furthermore, the bandwidth map further indicates information about the bandwidth allocated to the slave node by the master node, so that the slave node may transmit the request for bandwidth, which is based on the current traffic distribution of the slave node, to the master node to request the master node to provide a higher or more proper bandwidth when transmitting the data frame next time or next few times.
[0189] The embodiment of the disclosure further provides a computer storage medium having stored therein computer-executable instructions for executing the transmission method, applied to the master node, for the OBTN in the embodiment of the disclosure.
[0190] Referring to FIG. 8 , the embodiment of the disclosure provides a master node 60 , which may be applied to an OBTN. In order to clearly describe the embodiment of the disclosure, a structure of the OBTN is shown in FIG. 1 , and the master node 60 may include a measurement unit 601 , a calculation unit 602 , a first transmitting unit 603 , a first training unit 604 , a first receiving unit 605 and a generation unit 606 .
[0191] The measurement unit 601 may be configured to measure a network loop length of the OBTN, wherein the network loop length may include a loop length of a data channel of the OBTN and a loop length of a control channel of the OBTN;
[0192] The calculation unit 602 may be configured to calculate a length of a data frame, a length of the timeslot, the number of timeslots in the data frame, a guard interval for the timeslot and the like according to the loop length of the data channel in a result of the measurement of the measurement unit 601 ;
[0193] The first transmitting unit 603 may be configured to transmit a test data frame and a test control frame to a slave node according to the calculated length of the data frame, number of the timeslots in the data frame, length of the timeslot and guard interval for the timeslot.
[0194] In such case, the test control frame contains the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot.
[0195] The first training unit 604 may be configured to perform frame synchronization training and timeslot synchronization training according to the test data frame and test control frame transmitted by the first transmitting unit 603 .
[0196] The first transmitting unit 603 may be further configured to transmit the data frame and a control frame containing a bandwidth map according to results of the frame synchronization training and timeslot synchronization training performed by the first training unit 604 ;
[0197] The first receiving unit 605 may be configured to receive a request for bandwidth.
[0198] The generation unit 606 may be configured to perform bandwidth allocation calculation according to the request for bandwidth, and generate a new bandwidth map.
[0199] The first transmitting unit 603 may be further configured to transmit the new bandwidth map.
[0200] In an example, the measurement unit 601 may measure the network loop length of the OBTN during initialization of the OBTN, and specifically, the measurement unit 601 may measure a loop length of a control channel of the OBTN and a loop length of a data channel of the OBTN.
[0201] In such case, the step that the measurement unit 601 measures the loop length of the data channel of the OBTN may include that:
[0202] a certain node (such as the master node and a slave node) is caused to transmit an OB packet to the master node 60 , and the measurement unit 601 waits for successively receiving the OB packet twice; and
[0203] the measurement unit 601 measures time t 1 when the OB packet reaches the master node 60 for the first time and time t 1 when the OB packet reaches the master node 60 for the second time respectively, and then the loop length of the data channel is a first time difference t L1 of t 1 and t 2 , i.e. t L1 =t 2 −t 1 .
[0204] Correspondingly, after the loop length of the data channel is obtained, the calculation unit 602 may calculate a length of the timeslot of an OB according to the loop length, and the length of the timeslot of the OB includes: a length T of the OB packet and a guard interval T 1 between OB packets. The loop length t L1 of the data channel is an integral multiple of the length of the timeslot of the OB, i.e. t L1 =(T+T 1 )×N, wherein N represents the integral multiple, that is, the loop length of the OBTN includes totally N timeslots. The data frame also consists of timeslots of multiple OBs. Thus, in the embodiment, a data frame preferably includes timeslots of 10 OBs, and the loop length of the data channel is a length of 4 data frames, that is, N is 40.
[0205] It should be noted that the master node 60 is still required to perform loop length detection in real time to monitor a change in the network loop length and perform corresponding regulation to ensure that the loop length is an integral multiple of the length of the timeslot after the OBTN works normally.
[0206] The step that the measurement unit 601 measures the loop length of the control channel may include that:
[0207] the master node 60 transmits a header of a control frame at a certain time t 3 , and after the control frame is sequentially transmitted through each node in the ring network, the measurement unit 601 receives the header of the control frame at time t 4 , and then the loop length of the control channel is a second time difference t L2 between t 4 and t 3 , i.e. t L2 =t 4 −t 3 .
[0208] Since the control channel and the data channel are independent of each other and use different wavelengths, successive optical information packets, instead of OB packets, are transmitted via the control channel and optical-electric-optical processing and logical judgment are required before sequential transmission at each slave node in the control channel, It will be understood that the second time difference should be greater than the first time difference.
[0209] In an example, the first transmitting unit 603 is configured to transmit the test data frame to the slave node according to the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot. Specifically, a length of the test data frame transmitted by the first transmitting unit 603 may be equal to 10 OB timeslots, and the length of each timeslot is T+T 1 , wherein T 1 is the guard interval for the timeslot and T is the length of the OB packet; and moreover, the first transmitting unit 603 may also transmit the data frame when operating normally. It will be understood that a header of the data frame is virtual, and may specifically be the beginning of the first timeslot in the data frame.
[0210] The first training unit 604 is configured to measure the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node after the first transmitting unit 603 transmits the test data frame and the test control frame.
[0211] Alternatively, the first training unit 604 determine a difference value between t L2 and t L1 obtained by the measurement unit 601 as the time delay between time when the test control frame is returned to the master node and time when the test data frame is returned to the master node.
[0212] Specifically, after the first transmitting unit 603 transmits the test data frame and the test control frame, the first training unit 604 measures transmission time periods between transmitting and reception of the two frames respectively, and may obtain a time difference between the two transmission time periods. For example, the time difference may be a time delay between time when the test control frame is received and time when the test data frame is received, calculated by the first training unit 604 after the first transmitting unit 603 simultaneously transmits the test data frame and test control frame which have the same length. Alternatively, the time difference may be a time difference between: a period from time when the test data frame is transmitted by the first transmitting unit 604 to time when it is received, and a period from time when the test control frame is transmitted by the first transmitting node 604 to time when it is received, wherein the length of the test data frame is the same as that of the test control frame, and the test data frame and the test control frame are not transmitted simultaneously.
[0213] It should be noted that time for transmission of the test control frame in the OBTN is longer than time for transmission of the test data frame in the OBTN, because operation such as photoelectric conversion processing and logical judgment may be executed in the control channel.
[0214] Specifically, the time delay may be treated as a part of the time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame. Moreover, it will be understood the time delay accounts for a great proportion of the time interval.
[0215] In addition, the time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame may further include fragmentary time periods such as action time of optical switching of the nodes in the network and a time duration from starting to completion of transmission of a bandwidth map in the control frame, and then the time interval between time when the master node transmits the control frame and time when the master node transmits the data frame after transmitting the control frame is completely formed.
[0216] In an example, the OBTN may work normally after an initialization process of the OBTN; and when the OBTN works normally, the first transmitting unit 603 may transmit the data frame and the control frame to a downstream node in the OBTN. In the embodiment, the downstream node of master node A is slave node B, and node A transmits the data frame and the control frame to node B. The control frame contains the bandwidth map generated by the generation unit 606 , indicating the slave node to control reception and transmission of the data frame. For example, the bandwidth map may indicate that each node may and/or may not receive a certain or some timeslots in a certain or some wavelengths in the data frame, the slave node may and/or may not write data into a certain or some timeslots in a certain or some wavelengths in the data frame and the like, which timeslots may be received by the slave nodes or into which timeslots may be written by the slave nodes, or information about bandwidths which are allocated to the slave nodes by the master node 60 .
[0217] In an example, in the embodiment, after the first receiving unit 605 receives the requests for bandwidth from respective slave nodes, the generation unit 606 may perform bandwidth allocation calculation according to a current state of resources of the whole network and requests for bandwidth of respective slave nodes and perform wavelength and timeslot allocation for the respective nodes to generate the new bandwidth map by virtue of a DBA algorithm.
[0218] The embodiment of the disclosure provides the master node 60 , and by means of network loop length detection of the master node 60 and frame synchronization training and timeslot synchronization training of the nodes in the network, FDL is not required in the nodes in the network, a network design is simplified, construction cost of the OBTN is lowered, flexible construction of the OBTN is implemented without greatly limiting the throughput of the network, increase of an operation rate of the network and improvement of efficiency and throughput of the network are facilitated, and an effective rate of an optical network is fully utilized.
[0219] In the embodiment of the disclosure, in a practical application, the measurement unit 601 , calculation unit 602 , first training unit 604 and generation unit 606 in the master node 60 may be implemented in a Central Processing Unit (CPU), Digital Signal Processor (DSP) or Field Programmable Gate Array (FPGA) in the master node 60 ; the first transmitting unit 603 in the master node 60 may be implemented by a transmitter or transmission antenna in the master node 60 in the practical application; and the first receiving unit 605 in the master node 60 may be implemented by a receiver or receiving antenna in the master node 60 in the practical application.
[0220] Referring to FIG. 9 , the embodiment of the disclosure provides a slave node 70 , which may be applied to an OBTN, and in order to clearly describe the embodiment of the disclosure, a structure of the OBTN is shown in FIG. 1 , and the slave node 70 may include a second receiving unit 701 , a second training unit 702 , a reception and transmission control unit 703 and a second transmitting unit 704 .
[0221] The second receiving unit 701 may be configured to receive a test data frame and a test control frame.
[0222] The second training unit 702 may be configured to perform frame synchronization training and timeslot synchronization training according to the test data frame and test control frame received by the second receiving unit 701 .
[0223] The second receiving unit 701 may be further configured to receive a data frame and a control frame containing a bandwidth map.
[0224] The reception and transmission control unit 703 may be configured to control reception and transmission of each timeslot in the data frame according to the bandwidth map received by the second receiving unit 701 , a result of the frame synchronization training and a result of the timeslot synchronization training.
[0225] The second transmitting unit 704 may be configured to transmit a request for bandwidth.
[0226] The second receiving unit 701 may be further configured to receive a new bandwidth map.
[0227] In an example, the second training unit 702 may be configured to determine a time delay between time when a header of the test control frame is received and time when a header of the test data frame (i.e. a beginning of a first timeslot in the frame) is received as a reference time delay between time when the control frame is received by the slave node and time when the data frame is received by the slave node.
[0228] In the example, a time position at which each timeslot in the data frame is received is determined according to information about the number of timeslots in data frame, a guard interval for the timeslot and a length of the timeslot which are contained in the test control frame, wherein the second training unit 702 may acquire the guard interval for the timeslot and the length of the timeslot from the test control frame in the embodiment, so that the slave node 70 may calculate time of arrival of the first timeslot of the data frame according to the time delay between the control frame and the data frame when receiving the header of the control frame under a normal operating situation, and then determine the time position of each timeslot in the data frame to accurately receive each timeslot of the data frame according to the guard interval for the timeslot and the length of the timeslot.
[0229] In the example, accurate time at which a timeslot is transmitted by a node is determined according to the deviation of time, at which a timeslot is transmitted by the node, measured by another node. In the embodiment, when node B, for example, transmits a burst timeslot of the test data frame to node C, the burst timeslot containing information about a data frame No., a timeslot No., a source node and destination node of the transmission and the like, a substantial position T bin where a certain timeslot in a certain data frame is transmitted may be different from an ideal timeslot position (a current time position T ain at which the timeslot is transmitted by node A), node C may measure a deviation T ain −T bin of the timeslot transmitted by node B and report the deviation to node A, then node A feeds back the deviation T ain −T bin to node B through the control frame, and node B may regulate an accurate time position at which each timeslot of the data frame is transmitted by node B according to the deviation between T bin and T ain so as to transmit the burst timeslot at the accurate time position at which a timeslot is transmitted under the normal operating situation.
[0230] The timeslot of the test data frame is transmitted according to the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot, which are contained in the test control frame, as well as the accurate time at which a timeslot is transmitted. After performing the frame synchronization and timeslot synchronization training in the embodiment, the slave node may transmit the test data frame and the test control frame to the next node in the OBTN to enable the next node to implement frame synchronization and timeslot synchronization training according to the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot contained in the test control frame, as well as the results of training, and the regulated accurate time at which a timeslot is transmitted.
[0231] In an example, in a normal operating state of the OBTN, the second receiving unit 701 may determine the beginning of the first timeslot in the data frame after the reference time delay from when receiving the header of the control frame according to the reference time delay when receiving the timeslots of the data frame, and accurately receive each timeslot of the data frame at the accurate time positions according to the length of the data frame, the number of the timeslots in the data frame, the length of the timeslot and the guard interval for the timeslot contained in the current control frame.
[0232] During the reference time delay from time when the control frame is received, the slave node 70 may read control information such as bandwidth map from the control frame, and under the indication of the bandwidth map, determine which timeslots in the data frame will be received by the slave node and into which timeslots, data to be transmitted may be written by the slave node, such that the control of the reception and transmission control unit 703 can be performed on reception and transmission of each timeslot in the data frame.
[0233] Furthermore, the bandwidth map further indicates information about a bandwidth allocated to the slave node by the master node, so that the slave node 70 may transmit the request for bandwidth, which is based on its own current traffic distribution situation, to the master node through the second transmitting unit 704 to request the master node to provide a higher or more proper bandwidth when transmitting the data frame next time or next few times.
[0234] Specifically, in a data frame transmission situation shown in FIG. 5 , the number of OB timeslots in the data frame is 10, and in order to facilitate description, the first 6 timeslots are illustrated for description for node B and node C in FIG. 5 .
[0235] For node B, timeslots 1, 4 and 6 in a data frame transmitted through a data channel with a wavelength λ1 in the (K+3) th frame are timeslots which will be received by node B; timeslots 2, 3 and 5 in a data frame transmitted through a data channel with a wavelength λ2 in the (K+3) th frame are timeslots which will be received by node B; thus, the bandwidth map generated by the master node A may indicate the reception and transmission control unit 703 of node B to receive timeslots 1, 4 and 6 in the data frame transmitted through the data channel with the wavelength λ1 and timeslots 2, 3 and 5 in the data frame transmitted through the data channel with the wavelength.
[0236] After the (K+3) th frame is transmitted through node B, a service situation of each timeslot is shown in a distribution on the (K+2) th frame in FIG. 5 . Node B may write data to be transmitted into the timeslots in the data frame after receiving the data transmitted to node B in the timeslots, and the bandwidth map may also indicate sequence numbers of timeslots into which data may be written by node B. For example, the reception and transmission control unit 703 of node B fills data to be transmitted to node A into timeslot 1 in the data frame transmitted through the data channel with the wavelength λ1 and timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ2, fills data to be transmitted to node D into timeslots 4 and 6 in the data frame transmitted through the data channel with the wavelength λ1 and fills data to be transmitted to node C into timeslot 3 in the data frame transmitted through the data channel with the wavelength λ2.
[0237] Data frame reception and transmission of node B shows that node A allocates 6 reception and transmission timeslots to node B, and node B may transmit a request for bandwidth, which is based on the resource situation of node B, to node A through the second transmitting unit 704 to request for a higher or more proper bandwidth or a more proper inter-node pair bandwidth.
[0238] For node C, timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ1 in the (K+2) th frame are timeslots which will be received by node C; timeslots 3, 4 and 6 in the data frame transmitted through the data channel with the wavelength λ2 are timeslots which will be received by node C; thus, the bandwidth map generated in the master node A may indicate the reception and transmission control unit 703 of node C to receive timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ1 and timeslots 3, 4 and 6 in the data frame transmitted through the data channel with the wavelength λ2.
[0239] After the (K+2) th frame is transmitted through node C, a service situation of each timeslot is shown in a distribution on the (K+1) th frame, node C may write data to be transmitted into the timeslots in the data frame after receiving the data in the timeslots, and the bandwidth map may also indicate sequence numbers of timeslots into which data may be written by node C; for example, the reception and transmission control unit 703 of node C fills data to be transmitted to node D into timeslots 2 and 5 in the data frame transmitted through the data channel with the wavelength λ1 and timeslot 1 in the data frame transmitted through the data channel with the wavelength λ2, and fills data to be transmitted to node B into timeslot 3 in the data frame transmitted through the data channel with the wavelength λ2.
[0240] Similarly, node C may also transmit a request for bandwidth to node A through the second transmitting unit 704 , to request for a higher or more proper bandwidth.
[0241] The process that node D controls reception and transmission of the data frame and transmits a request for bandwidth to the master node is the same as those of node B and node C, and will not be elaborated herein.
[0242] It should be noted that timeslot reusability is higher in the embodiment of the disclosure and a node may transmit data with a timeslot after the same timeslot is received by another node in downstream of the node, so that a transmission rate of the network is increased.
[0243] The embodiment of the disclosure provides the slave node 70 , and frame synchronization and timeslot synchronization training may be performed according to the test data frame and test control frame transmitted by the master node, so that FDL is not required in the nodes in the network, a network design is simplified, construction cost of the OBTN is lowered, flexible construction of the OBTN is implemented without greatly limiting the throughput of the network, increase of an operation rate of the network and improvement of efficiency and throughput of the network are facilitated, and an effective rate of an optical network is fully utilized.
[0244] In the embodiment of the disclosure, the second training unit 702 and reception and transmission control unit 703 in the slave node 70 may be implemented in a CPU, DSP or FPGA in the slave node 70 in a practical application; the second transmitting unit 704 in the slave node 70 may be implemented by a transmitter or transmission antenna in the slave node 70 in the practical application; and the second receiving unit 701 in the slave node 70 may be implemented by a receiver or receiving antenna in the slave node 70 in the practical application.
[0245] FIG. 10 is a schematic diagram of a node device 80 for an OBTN according to an embodiment of the disclosure, in which specific structures of the master node 60 and slave node 70 in the abovementioned embodiment may be schematically described in summary. In FIG. 10 , the full thick line is an optical signal, the thin solid line is an electric signal, the dotted part is a part only existing in the master node 60 , and when the dotted part is omitted, the node device 80 shown in FIG. 10 may represent the slave node 70 .
[0246] The node device 80 includes a wave splitter 801 , a control channel transceiving and processing unit 802 , a combiner 803 , an OB switching unit 804 , a burst receiving and transmitting unit 805 , a client-side traffic processing unit 806 , a synchronization processing unit 807 , a bandwidth map allocation unit 808 and the like.
[0247] The wave splitter 801 separates wavelength λc for a control channel from wavelength λd for a data channel.
[0248] The control channel transceiving and processing unit 802 is configured to receive data in the control channel wavelength, perform control on data reception and transmission according to the data, and simultaneously generate a new control frame.
[0249] The combiner 803 combines the wavelength λc for the control channel and the wavelength λd for the data channel, and outputs them as a whole to a line-side optical link for transmission.
[0250] The OB switching unit 804 implements switching of an OB packet, including uplink and downlink control and optical conduction, optical attenuation and/or optical attenuation control, to implement timeslot-based burst packet switching control for different wavelengths.
[0251] The burst receiving and transmitting unit 805 implements burst reception and burst transmitting of line-side data.
[0252] The client-side traffic processing unit 806 receives, transmits and caches data at the client-side, and performs data interaction with the burst receiving and transmitting unit 805 according to control.
[0253] The synchronization processing unit 807 realizes functions of timeslot synchronization, clock synchronization and the like for burst switching.
[0254] The bandwidth map allocation unit 808 implements statistics about requests for bandwidth among nodes in the whole network, and performs calculation for bandwidth map allocation.
[0255] The wavelength λc for the control channel and wavelength λd for the data channel splitted by the wave splitter 801 are transmitted to the control channel transceiving and processing unit 802 and the OB switching unit 804 respectively. At the master node, the control channel transceiving and processing unit 802 receives data transmitted via the wavelength λc, controls the OB switching unit 804 , the client-side traffic processing unit 806 , the burst receiving and transmitting unit 805 and the synchronization processing unit 807 according to information of a bandwidth map contained in the data, and transmits the requests for bandwidth uploaded by each slave node through the wavelength λc and its own request for bandwidth to the bandwidth map allocation unit 808 . At each slave node, the control channel transceiving and processing unit 802 receives the data transmitted via the wavelength λc, extracts bandwidth map information transmitted to the slave node by the master node from the data, controls the OB switching unit 804 , the client-side traffic processing unit 806 , the burst receiving and transmitting unit 805 and the synchronization processing unit 807 according to the bandwidth map information, adds its own request for bandwidth into a message field of the wavelength λc, and transmits the request for bandwidth to the next node until the request for bandwidth is transmitted to the master node.
[0256] The synchronization processing unit 807 calculates a frame length, a timeslot number and a length of a guard interval according to a result of the loop length detection, and detects a timeslot synchronization state of each wavelength to ensure that the node may receive and transmit a burst timeslot at correct time points. If there exists a deviation about time for receiving and transmitting the burst timeslot, a timeslot synchronization function may be realized after detection and correction of the synchronization processing unit 807 . Moreover, a clock transmission function may be realized, that is, a system clock is transmitted according to a control channel, and the clock is determined as a reference clock for reception and transmission of a data channel. Specifically: at the master node, a clock based on a local clock is transmitted to a control channel generator and the burst receiving and transmitting unit 805 of the node, and is determined as a reference clock of these receiving and transmitting units; and at the slave node, a clock based on a clock recovered by the control channel transceiving and processing unit 802 is transmitted to the control channel generator and the burst receiving and transmitting unit 805 of the node, and is determined as a reference clock of these receiving and transmitting units.
[0257] The OB switching unit 804 and the burst receiving and transmitting unit 805 implement control over reception and transmission on correct wavelengths and correct timeslots, or switching-on and off of the timeslots, optical power regulation and the like according to the allocation information of the bandwidth map and control of the synchronization processing unit 807 . The OB switching unit 804 receives the data wavelength λd on a line-side optical link, and controls reception and transmission, switching on and off, optical power regulation and the like on each wavelength and each timeslot to realize an OB switching function of the wavelengths and the timeslots according to the allocation information of the bandwidth map; and the burst receiving and transmitting unit 805 is required to implement selective reception and adjustable transmitting of an OB packet, reception and transmission being required to be strictly performed on correct timeslots under the control of the synchronization processing unit 807 , and interact with the client-side traffic processing unit 806 about received and transmitted burst data.
[0258] The client-side traffic processing unit 806 caches the data received and transmitted at a client side, generates a request for bandwidth according to the volume of cached data to be transmitted to another node, and transmits request for bandwidth information to the control channel transceiving and processing unit 802 .
[0259] The bandwidth map allocation unit 808 is located in the master node, and does not exist in the slave node. The bandwidth map allocation unit 808 receives the requests for bandwidth of respective nodes from the control channel transceiving and processing unit 802 , performs bandwidth map allocation calculation according to resources (such as the number of wavelengths and the number of timeslots) which may be allocated in an OB switching network and an allocation rule (such as adjustable transmitting, selective reception, relative positions of each node in the network and the number of transceiver ports), and transmits a result of final calculation to the control channel transceiving and processing unit 802 .
[0260] It will be understood that the control channel transceiving and processing unit 802 , client-side traffic processing unit 806 , synchronization processing unit 807 and bandwidth map allocation unit 808 in the node device 80 may specifically be implemented in a CPU, a Micro Processing Unit (MPU), a Digital signal processor (DSP), an Field Programmable Gate Array (FPGA) or the like, and a specific hardware implementation process is a conventional technical means adopted by those skilled in the art, and will not be elaborated herein.
[0261] FIG. 11 is a schematic diagram of another node device 90 according to an embodiment of the disclosure, the node device 90 includes an optical amplifier 901 , a first wave splitter 902 , a control channel receiving and processing unit 903 , a control channel generation and transmitting unit 904 , a clock processing unit 905 , an OB receiver 906 , a high-speed tunable burst transmitter 907 , a second wave splitter 908 , a high-speed Variable Optical Attenuator (VOA) array 909 , an Optical Coupler (OC) 910 , a combiner 911 , an OB de-framing and framing unit 912 , a traffic monitoring unit 913 , a client-side traffic access processing unit 914 , a DBA unit and loop length statistic unit 915 , a detection and control unit 916 , a failure detection unit 917 and the like, and a specific operating manner of each unit is described below.
[0262] The optical amplifier 901 may specifically be an ordinary-mode optical amplifier, or a burst-mode optical amplifier. If the ordinary-mode optical amplifier is selected, it is necessary to strictly control optical power to keep the optical power stable without great optical power jitter within a short time, thereby amplifying optical power in a burst channel to make it possible to transmit an optical signal of an OBTN for a longer distance and compensate for optical power loss caused by each splitting unit; and in addition, if a control channel adopts a wavelength of 1,510 nm for transmission, the optical amplifier 901 performs wave splitting and combination on an optical signal with the wavelength of 1,510 nm transmitted in the control channel to implement reception and transmission of the control channel.
[0263] The control channel receiving and processing unit 903 is configured to implement signal receiving and processing of the control channel, and the processing includes clock recovery, extraction of information from bandwidth map, extraction of information from the request for bandwidth and the like, and may also include information about other control, alarming and the like. No matter whether the control channel adopts the wavelength of 1,510 nm or a wavelength of 1,550 nm, reception may be implemented, and a transmission rate is optionally 10.709 Gbps. When the node device 90 is a slave node 70 , a recovered clock is transmitted to the clock processing unit 905 ; and when the node device 90 is a master node 60 , the recovered clock is not required to be transmitted to the clock processing unit 905 .
[0264] The control channel generation and transmitting unit 904 is configured to implement signal regeneration and transmitting of the control channel; and the control channel generation and transmitting unit 904 receives traffic information generated by the client-side traffic access processing unit 914 , and receives traffic monitoring information generated by the traffic monitoring unit 913 . The clock transmitted at each node is a clock output by the clock processing unit 905 .
[0265] The clock processing unit 905 is configured to realize a clock transmission function of the control channel, and determine the clock as a reference clock for reception and transmission of a data channel. When the node device 90 is the master node 60 , a clock based on a local clock is transmitted to the control channel generation and transmitting unit 904 , the OB receiver 906 and the high-speed tunable burst transmitter 907 , and is determined as a reference clock of these units; and when the node device 90 is the slave node 70 , a clock based on a clock recovered by the control channel receiving and processing unit is transmitted to the control channel generation and transmitting unit 904 , the OB receiver 906 and the high-speed tunable burst transmitter 907 , and is determined as a reference clock of these units.
[0266] The OB receiver 906 is configured to implement reception of a burst signal at a line-side of the OBTN. A wideband receiver is adopted, burst optical signals of respective wavelengths within a wavelength band of 1,550 nm may be received, a rate is preferably 10.709 Gbps, and an internal amplifier may implement amplification of a burst packet.
[0267] The high-speed tunable burst transmitter 907 is configured to implement transmitting of signal at the line-side of the OBTN. A high-speed tunable laser with a wavelength interval of 50 GHz or 100 GHz is adopted, a burst optical signal is transmitted at 10.709 Gbps, and the aim of wavelength-tunable transmitting is fulfilled.
[0268] The high-speed variable optical attenuator (VOA) array 909 implements switching-on and off control and optical power control of an OB. A switching-on and off control speed of each VOA is lower than 1 μs, and high-speed switching-on and off selection of reception and transmission of an OB packet is implemented to fulfil the aim of optical switching. In addition, the aim of accurately controlling optical power of the OB packet may be fulfilled by optical power attenuation over each OB timeslot. If the high-speed tunable burst transmitter 907 has an optical power adjustment function, the VOAs connected to the high-speed tunable burst transmitter may be omitted.
[0269] The wave splitters, the OC 910 and the combiner 911 realize functions of wavelength separation, equal splitting or combination of optical power of a signal and wavelength convergence. The wave splitters may include the first wave splitter 902 and the second wave splitter 908 , the former implements separation of the wavelength of 1,510 nm and wavelengths within the wavelength band of 1,550 nm, and the latter implements separation of the wavelengths within the wavelength band of 1,550 nm according to the interval of 50 GHz or 100 GHz.
[0270] The OB de-framing and framing unit 912 is configured to encapsulate and decapsulate traffic in form of burst packet and implements reception and transmission of a line-side traffic and packing and unpacking of the OB packet. During reception, a complete Optical Burst Unit (OBU) is found according to an OBU delimiter in the received data, and then is decapsulated to recover the data according to a definition about an OBU; and during transmitting, the burst packet is encapsulated according to the definition about the OBU.
[0271] The traffic monitoring unit 913 is configured to perform traffic management and control on received and transmitted traffic according to a certain rule to ensure the volume of traffic received and transmitted by a client side of each node wholly substantially equal to the volume of traffic received and transmitted on a line side to avoid congestion and implement management over traffic levels and the like.
[0272] The client-side traffic access processing unit 914 is configured to perform operations, such as queuing according to destination nodes, the traffic levels and the like, on the traffic on the client side. The client-side traffic access processing unit 914 reports traffic information such as depths of each queue to the control channel generation and transmitting unit 904 to form a request for bandwidth for reporting to the master node after queuing the traffic according to the destination nodes and the traffic levels.
[0273] The DBA unit and loop length statistic unit 915 performs bandwidth map allocation calculation according to a bandwidth report, measures a loop length of the network and calculates related attribute parameters such as a frame length and a guard interval for the timeslot. Only the master node 60 has such a function, performs bandwidth requirement cutting from the bandwidth reports uploaded by each slave node 70 , implements DBA timeslot and wavelength allocation calculation, and performs loop length detection to further calculate the attribute parameters such as the length of data frame and the guard interval for the timeslot to ensure that the loop length is an integral multiple of the frame length.
[0274] The detection and control unit 916 implements control over reception and transmission over the data channel according to the information of bandwidth map. When the node device 90 is the slave node 70 , control over reception and transmission of an OB packet on the data channel is implemented according to the bandwidth map transmitted by the master node 60 , and adaption and framing operation is performed on data; and in addition, it is also necessary to detect a time deviation between a data frame and a control frame, perform accurate detection on an OB timeslot and determine accurate time of reception and transmission of the OB according to a result of the detection. The master node 60 is further required to detect whether the data frame is overlapped or not and whether it is necessary to regulate initial transmitting time of the control frame or not according to such a function unit.
[0275] The failure detection unit 917 is configured to monitoring operating states of the network and the nodes and optical power, and detect a magnitude of optical power of each OB, whether time positions of the OBs are abnormal or not, abnormalities of system clock transmission and the like.
[0276] It will be understood that the control channel receiving and processing unit 903 , control channel generation and transmitting unit 904 , clock processing unit 905 , OB de-framing and framing unit 912 , traffic monitoring unit 913 , client-side traffic access processing unit 914 , DBA unit and loop length statistic unit 915 , detection and control unit 916 and failure detection unit 917 in the node device 90 may specifically be implemented in a Central Processing Unit (CPU), a Micro Processing Unit (MPU), a Digital Signal Processor (DSP), a Field Programmable Gate Array (FPGA) or the like in a practical application, and a specific hardware implementation process is a conventional technical means adopted by those skilled in the art, and will not be elaborated herein.
[0277] Based on the abovementioned embodiment, the embodiment of the disclosure further provides an OBTN 100 , and its structure diagram is shown in FIG. 12 , including the master node 60 and at least one slave node 70 .
[0278] The master node 60 is recited in any abovementioned embodiment and the at least one slave node 70 is recited in any abovementioned embodiment.
[0279] In the embodiments provided by the disclosure, it should be understood that the disclosed system, device and method may be implemented in other forms. For example, the device embodiment described above is only schematic, and for example, division of the modules or units is only division in terms of logical functions, and other division manners may be adopted in practical implementation. For example, multiple units or components may be combined or integrated into another system, or some characteristics may be omitted or not performed. In addition, displayed or discussed coupling or direct coupling or communication connection therebetween may be indirect coupling or communication connection implemented through some interfaces, devices or units, and may also be electrical and mechanical or adopt other forms.
[0280] The units described as separate parts may or may not be physically separated, and parts shown as units may or may not be physical units, and namely may be located in the same place or distributed to multiple network units. Part or all of the units may be selected to fulfil the aim of the solutions of the embodiment according to a practical requirement.
[0281] In addition, each function unit in each embodiment of the disclosure may be integrated into a processing unit, each unit may also physically exist independently, and two or more units may also be integrated into a unit. The integrated unit may be implemented in a hardware form, and may also be implemented in form of software function unit.
[0282] When being implemented in form of software function unit and sold or used as an independent product, the integrated unit may be stored in a computer-readable storage medium. Based on such an understanding, the technical solutions of the disclosure substantially or parts making contributions to a conventional art or all or part of the technical solutions may be embodied in form of software product, and the computer software product is stored in a storage medium having contained therein a plurality of instructions to enable a computer equipment (which may be a personal computer, a server, network equipment or the like) or processor to execute all or part of the steps of the embodiment of each embodiment. The storage medium includes various medium capable of storing program codes such as a U disk, a mobile hard disk, a Read-Only Memory (ROM), a magnetic disc or a compact disc.
[0283] The above is only the specific implementation mode of the disclosure and not intended to limit the scope of protection of the disclosure, and any variations or replacements apparent to those skilled in the art within technical scope of the disclosure shall fall within the scope of protection of the disclosure. Therefore, the scope of protection of the disclosure shall be subject to the scope of protection of the claims.
INDUSTRIAL APPLICABILITY
[0284] According to the embodiment of the disclosure, by network loop length detection of the master node and frame synchronization training and timeslot synchronization training over the nodes in the network, the network design may be simplified, construction cost of the OBTN may be lowered, flexible construction of the OBTN may be implemented without greatly limiting the throughput of the network, and increase of the operation rate of the network and improvement of the efficiency and throughput of the network are facilitated. | Disclosed are an optical burst transport network, a node, a transmission method and a computer storage medium. The method comprises: measuring, by a master node, the network ring length of an OBTN, and according to a measurement result, calculating the length of a data frame, the number of time slots in the data frame, the length of the time slots and the guard interval of the time slots; according to the calculated length of the data frame, the number of time slots in the data frame, the length of the time slots and the guard interval of the time slots, sending a testing data frame and a testing control frame to a slave node to conduct frame synchronization training and time slot synchronization training; according to a result of the frame synchronization training and a result of the time slot synchronization training, sending, by the master node, a data frame and a bandwidth map to the slave node; and according to a bandwidth request sent from the node, generating, by the master node, a new bandwidth map, and sending the new bandwidth map to the slave node. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
This application is the US National Stage of International Application No. PCT/DE03/00953, filed Mar. 21, 2003 and claims the benefit thereof. The International Application claims the benefits of German application No. 10215374.4 DE filed Apr. 8, 2002, and German application No. 10259365.5 DE filed Dec. 18, 2002, all of the applications are incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
The invention relates to an apparatus and a process for removing surface regions of a component as described in the claims.
BACKGROUND OF THE INVENTION
Hitherto, components which have been coated with coatings of type MCrAlY or ZrO 2 have had the coating removed, for example, by acid stripping in combination with sand blasting or by high-pressure water blasting.
EP 1 122 323 A1 and U.S. Pat. No. 5,944,909 show examples of the chemical removal of surface regions.
EP 1 941 34 A1, EP 1 010 782 A1 and U.S. Pat. No. 6,165,345 disclose methods for the electrochemical removal of metallic coatings (stripping).
The processes listed above are time-consuming and therefore expensive.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an apparatus and a process in which the removal of the coating takes place more quickly and economically.
The object is achieved by an apparatus and a process for the removal of surface regions from a component as described in the claims.
Further advantageous configurations and process steps are listed in the corresponding subclaims.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawing:
FIG. 1 shows an apparatus according to the invention,
FIG. 2 shows a time curve of a current of a current pulse generator, and
FIG. 3 shows a further time curve of a current from a current pulse generator.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an apparatus 1 according to the invention. The apparatus 1 comprises a vessel 4 in which an electrolyte 7 there is arranged. An electrode 10 and a component 13 are arranged in the electrolyte 7 . The electrode 10 and the component 13 are electrically connected to a current/voltage pulse generator 16 . The component 13 is, for example, a coated turbine blade or vane, the substrate of which is a nickel- or cobalt-base superalloy, to which a metallic layer has been applied to serve, for example, as a corrosion-resistant or anchoring layer. A layer of this type in particular has the composition MCrAlY, where M stands for an element iron, cobalt or nickel.
The coating has been corroded during use of the turbine blade or vane 13 . The surface region 25 which has been formed as a result (as indicated by dashed lines) is to be removed by the process according to the invention and the apparatus 1 according to the invention. It is also possible for layer regions 25 which have been formed by corrosion, oxidation or other forms of degradation to be removed from a component 13 which does not have a coating, these layer regions being in the vicinity of the surface.
The current pulse generator 16 generates a pulsed current/voltage signal ( FIG. 2 ).
An ultrasound probe 19 , which is operated by an ultrasound source 22 , may optionally be arranged in the electrolyte 7 . The ultrasound excitation improves the hydrodynamics of the process and thereby assists the electrochemical reaction.
FIG. 2 shows an example of a current/voltage curve of the current/voltage pulse generator 16 .
The current pulse signal or the voltage pulse is, for example, square-wave (pulse shape) and has a pulse duration t on . Between the individual pulses there is an interval of length t off . Furthermore, the current pulse signal is defined by its current level I max .
The current (I max ) which flows between the electrode 10 and the component 13 , the pulse duration (t on ) and the pulse interval (t off ) have a significant influence on the electrochemical reaction by accelerating the latter.
FIG. 3 shows an example of a series of current pulses 40 which are repeated. A sequence 34 comprises at least two blocks 77 . Each block 77 comprises at least one current pulse 40 . A current pulse 40 is characterized by its duration t on , the level I max and its pulse shape (square-wave, delta, etc.). Other important process parameters are the intervals between the individual current pulses 40 (t off ) and the intervals between the blocks 77 .
The sequence 34 comprises, for example, a first block 77 of three current pulses 40 between each of which there is an interval. This is followed by a second block 77 , which has a higher current level and comprises six current pulses 40 . After a further interval, there then follow four current pulses 40 in the opposite direction, i.e. with a reversed polarity.
The sequence 34 is finished by a further block 77 of four current pulses. The sequence 34 can be repeated a number of times.
The individual pulse times t on are preferably of the order of magnitude of approximately 1 to 10 milliseconds. The time duration of the block 77 is of the order of magnitude of up to 10 seconds, so that up to 500 pulses are emitted in one block 77 .
The application of a low potential (base current) both during the pulse sequences and during the intervals is optionally possible.
The parameters of a block 77 are matched to a constituent of an alloy which, by way of example, is to be removed in order to optimize the removal of this constituent. This can be determined in individual tests. | Apparatus and process for removing surface regions of a component. The prior art involves removing surface regions of a metallic component by means of electrochemical processes. The electrochemical process is accelerated by the use of a current pulse generator. | 2 |
TECHNICAL FIELD
[0001] Embodiments of the present disclosure relate to an absolute signal consistency correction method for an absolute grating scale, which belongs to a field of measurement of the absolute grating scale.
BACKGROUND
[0002] An absolute grating scale is mainly used as a full-closed loop in a high-end numerical control system, and has advantages that absolute positions can be obtained as long as the system is powered on, a zero position does not need to be searched, and moreover, optical detection is adopted, and the absolute grating scale is not wearable due to adoption of a non-contact structure. The absolute grating scale is a necessary key part in the numerical control industry in the future.
[0003] According to the absolute grating scale, absolute position codes are engraved on a glass scale board, and are projected onto a photodiode array by irradiation of parallel light, the photodiode array converts optical signals with absolute position information into electric signals, and the absolute positions can be known through analysis. However, due to some adverse factors such as nonuniform illumination intensity, low absolute code engraving quality, nonuniform photoelectric response of the photodiode array and the like, the finally output electric signals with the absolute positions are inconsistent, accurate judgment on the absolute positions is influenced, and accuracy of the absolute grating scale is reduced.
[0004] Therefore, in the production and manufacturing process of the absolute grating scale, a consistency correction method is required to make up the detects such that the absolute signals finally output by the absolute grating scale can accurately and precisely reflect the real absolute positions.
[0005] A method for consistency correction method of a photoelectric converter and its processing circuit is disclosed, as in the Chinese Patent Publication No. CN102300057A, which has a title of “Method for correcting response inconsistency of linear array CCD (Charge Coupled Device) image elements”. The patent discloses that response inconsistency of CCD image elements is corrected by a formula of S i =k i (y i −(b i *DC+c i *g)), and then digital gain adjustment is carried out on the correction result by a formula of p i =k*s i , where p i represents a result after the digital gain adjustment, and k represents a gain factor. This method only corrects response inconsistency of CCD image elements in a manner of changing the gain factor and thus has problems that the liner range of the photoelectric response is narrow and signal dispersion is large.
SUMMARY
[0006] In order to solve the problems that the liner range of the photoelectric response is narrow and signal dispersion is large, of the existing consistency correction method of a photoelectric converter and its processing circuit, the present disclosure provides an absolute signal consistency correction method for the absolute grating scale so as to reinforce quality of the absolute signals and improve measurement accuracy of a system.
[0007] The technical solution of the present disclosure to solve the technical problem is:
[0008] As shown in FIG. 1 , an absolute signal voltage value consistency correction method for the absolute grating scale adopts a formula below:
[0000] v=P ·(1+ A )·1 +Q ·(1+ A )·( C−D )+ D (1)
[0000] where, v represents a voltage value output by a photodiode array and an amplifying and sampling holding circuit array after processing of a consistency correction structure; I represents a bias current of a light source; P and Q represent two constant coefficient vectors of the photodiode array and the amplifying and sampling holding circuit array; D represents a constant voltage value; A represents a correction vector of a gain correction circuit of the photodiode array and the amplifying and sampling holding circuit array; and C represents a correction vector of a bias correction circuit of the photodiode array and the amplifying and sampling holding circuit array;
[0009] The formula (1) is simplified as
[0000] v=K· 1+ B (2)
[0000] wherein,
[0000] K=P ·(1+ A ) (3)
[0000] B=Q ·(1+ A )·(C−D)+ D (4)
[0000] Characterized in that, the method comprises steps of
[0010] S1: by a host computer, respectively inputting two groups of initial correction data vectors a 1 [1:n] and b 1 [1:n] to the gain correction circuit and the bias correction circuit through a storage, then respectively regulating bias currents of the light source into I 1 , I 2 , I 3 , . . . , I m from weak to strong, where m represents a grade number of regulation, and simultaneously recording voltage values v1 1 [1:m], v1 2 [1: m], v1 3 [1: m], . . . , v1 n [1: m] output by the n photodiodes under m grades of bias currents of the light source after processing of the consistency correction structure.
[0011] S2: carrying out linear fitting on response curves of the voltage values output by the n photodiodes under m grades of bias currents of the light source after processing of the consistency correction structure obtained in the step S1, as shown in FIG: 3 , and then calculating slope vectors K[1:n] and intercept vectors B[1:n] of response straight lines of voltage values output by the n photodiodes under m grades of bias currents of the light source after processing of the consistency correction structure, so that the 2n constant coefficient vectors P[1:n] and Q[1:n] of the photodiode array and the amplifying and sampling holding circuit array can be obtained;
[0012] S3: selecting one of the n response straight lines obtained in the step S2 as a target straight line, fitting the other n-1 response straight lines to the target response straight line, as shown in FIG. 4( a ) , to obtain correction data vectors a 2 [1: n] of the gain correction circuit and correction data vectors b 2 [1: n] of the bias correction circuit;
[0013] S4: by the host computer, inputting the correction data vectors a 2 [1: n] and the correction data vectors b 2 [1: n], which are obtained in the step S3, into the gain correction circuit and the bias correction circuit through the storage, then regulating the bias current of the light source into an intermediate value I m/2 , and simultaneously recording voltage values v2 1 [m/2], v2 2 [m/2], v2 3 s[m/2], . . . , v2 n [m/2] output by the n photodiodes under the bias current of the light source;
[0014] S5: carrying out averaging on n voltage values v2 1 [m/2], v2 2 [m/2], v2 3 [m/2], . . . , v2 n [m/2] obtained in the step S4, then translating all the response straight lines of the output voltages towards an average value, as shown in FIG. 4( b ) , and only regulating the correction data vectors of the bias correction circuit to obtain a group of new correction data vectors b 3 [1: n];
[0015] S6: repeating the step S4 and the step S5 until dispersions of the response straight lines of the out voltages meet requirements, and then obtaining correction data vectors a 2 [1: n] of the gain correction circuit and correction data vectors b 4 [1: n] of the bias correction circuit;
[0016] S7: carrying out linearity range expansion on the response straight lines of the output voltages, which are obtained in the step S6, as shown in FIG. 5 , slightly increasing each value in the correction data vectors a 2 [1: n] of the gain correction circuit, and slightly reducing each value of the correction data vectors b 4 [1: n] of the bias correction circuit, so as to obtain new correction data vectors a 3 [1: n] of the gain correction circuit and new correction data vectors b 5 [1: n] of the bias correction circuit;
[0017] S8: by the host computer, transmitting the correction data vectors a 3 [1: n] of the gain correction circuit and the correction data vectors b 5 [1: n] of the bias correction circuit to the gain correction circuit and the bias correction circuit through the storage, detecting whether linearity ranges of the response straight lines of the output voltages meet requirements, and if no, repeating the step S7 until the requirements are met, so as to obtain correction data vectors a 4 [1: n] of the gain correction circuit and correction data vectors b 6 [1: n] of the bias correction circuit;
[0018] S9: detecting whether the dispersions of the response straight lines of the output voltages at the moment meet requirements, and if no, respectively inputting, by the host computer, two groups of new initial correction data a 4 [1: n] and b 6 [1: n] to the correction data vectors of the gain correction circuit and the correction data vectors of the bias correction circuit through the storage, and repeatedly executing the steps S1 to S9 until the dispersions and the linearity ranges of the response straight lines of the output voltages meet the requirements.
[0019] Advantageous effects of the present disclosure are that: the present disclosure solves the problem of inconsistency of finally output electrical signals with absolute positions, which is caused by factors such as nonuniform illumination intensity, low absolute code engraving quality, inconsistency of the photoelectric response of the photodiode array and the amplifying and sampling holding circuit, which reduces requirements of the absolute grating scale on selecting a lighting source, and in the meantime lowers difficulty in designing the amplifying and sampling holding circuit of the absolute grating scale, decreases the dispersions of the finally output electrical signals with absolute positions, increases the linear ranges of the absolute signals, reinforces quality of the absolute signals, improve measurement accuracy of a system, and achieves integration of the photodiode array, the amplifying and sampling holding circuit, the bias correction circuit, the gain correction circuit and the storage on one piece of silicon slice, and increases the speed and efficiency of reading the correction data;
[0020] The present disclosure realizes automatically performing a process step that the host computer carries out program control to dynamically regulate the consistency of the absolute signals of the absolute grating scale, which provides a basic condition for quickly and efficiently demarcating other key parameters of the absolute grating scale, and greatly improves the production efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a flow chart of an absolute signal consistency correction method for an absolute grating scale according to the present disclosure.
[0022] FIG. 2 is a structural schematic diagram of a system adopted by the absolute signal consistency correction method for the absolute grating scale according to the present disclosure.
[0023] FIG. 3 is a schematic diagram of after linear fitting the n voltage response cuves according to the present disclosure.
[0024] FIG. 4 is a schematic diagram of a process of translating the n response straight lines to an average value according to the present disclosure; FIG. 4( a ) is a schematic diagram before translating, and FIG. 4( b ) is a schematic diagram after translating.
[0025] FIG. 5 is a schematic diagram of response straight lines of voltages output by the photodiode array and the amplifying and sampling holding circuit after processing of a consistency correction structure, which are subjected to linearity range expansion, according to the present disclosure.
[0026] FIG. 6 shows response curves of voltages output by 20 photodiodes and 20 amplifying and sampling holding circuits after processing of the consistency correction structure in the initial data correction process in an embodiment of the present disclosure.
[0027] FIG. 7 shows translated response straight lines of the voltages output by 20 photodiodes and 20 amplifying and sampling holding circuits after processing of the consistency correction structure in the embodiment of the present disclosure.
[0028] FIG. 8 shows response straight lines of the voltages output by 20 photodiodes and 20 amplifying and sampling holding circuits after processing of the consistency correction structure, which are subjected to linearity range expansion, in the embodiment of the present disclosure.
DETAILED DESCRIPTION
[0029] A method provided by the present disclosure will be further illustrated in details in connection with the drawings and embodiments in the following.
[0030] As shown in FIG. 2 , a system structure adopted by an absolute signal consistency correction method for an absolute grating scale includes a light source 1 , a collimating lens 2 , a grating scale 3 on which absolute codes are engraved, a photodiode array 4 , an amplifying and sampling holding circuit array 5 , a bias correction circuit 6 , a gain correction circuit 7 , a consistency correction structure 8 , a storage 9 and a host computer 10 , wherein, the consistency correction structure 8 includes the bias correction circuit 6 and the gain correction circuit 7 . The photodiode array 4 , the amplifying and sampling holding circuit array 5 , the bias correction circuit 6 , the gain correction circuit 7 and the storage 9 are integrated on one silicon slice.
[0031] The system structure adopts a working principle that firstly, a system is powered on, and the host computer 10 transmits initial correction data vectors a 1 [1: n] of the gain correction circuit 7 and initial correction data vectors b 1 [1: n] of the bias correction circuit 6 to the storage 9 ; the light source 1 can emit light with corresponding intensities by regulating bias currents of the light source 1 , the light passes through the collimating lens 2 to generate parallel light, and after the parallel light passes through the grating scale 3 on which the absolute codes are engraved, the photodiode array 4 receives optical signals with the absolute codes and outputs n light currents with absolute code information, and then the amplifying and sampling holding circuit array 5 carries out amplifying and sampling holding processing on the n light currents and outputs n voltage signals with the absolute code information; the bias correction circuit 6 requests the correction data vectors b 1 [1: n] of the bias correction circuit 6 for the storage 9 , correction vectors C of the bias correction circuit 6 are formed by a D/A (Digital-to-Analog) conversion circuit, simultaneously, the gain correction circuit 7 requests the correction data vectors a 1 [1: n] of the gain correction circuit 7 for the storage 9 , and the correction data vectors a 1 [1: n] are converted into correction vectors A of the gain correction circuit 7 . The bias correction circuit 6 and the gain correction circuit 7 correct the voltage signals with the absolute code information, which are output by the amplifying and sampling holding circuit array 5 and uploads corrected voltages to the host computer 10 , and the host computer 10 judges whether linearity ranges and dispersions of response straight lines of voltages output by the photodiode array 4 and the amplifying and sampling holding circuit array 5 of the absolute grating scale under m grades of bias currents of the light source 1 after processing of the consistency correction structure 8 meet requirements.
EMBODIMENTS
[0032] The absolute signal consistency correction method for the absolute grating scale specifically includes steps of:
[0033] S1: by the host computer 10 , respectively inputting two groups of initial correction data vectors a 1 [1:n] and b 1 [1:n] to the gain correction circuit 7 and the bias correction circuit 6 of the consistency correction structure 8 of the photodiode array 4 ( 20 photodiodes are selected) and the amplifying and sampling holding circuit array 5 ( 20 amplifying and sampling holding circuits are selected) of the absolute grating scale through the storage 9 ; supposing that each element value in the correction data vectors a 1 [1:n] of the gain correction circuit 7 is 15 and each element value in the correction data vectors b 1 [1:n] of the bias correction circuit 6 is 32.
[0034] A rated bias current of the adopted light source 1 is 50 mA, 8 bias current grades of the light source 1 are taken respectively as 2.5 mA, 7.0 mA, 11.0 mA, 15.5 mA, 19.5 mA, 23.5 mA, 28.0 mA and 32.0 mA., bias currents of the light source 1 are regulated respectively to the above 8 values, voltage values v1 1 [1:8], v1 2 [1: 8], v1 3 [1: 8], . . . , v1 20 [1: 8] output by the 20 photodiodes and the 20 amplifying and sampling holding circuits under each bias current of the light source 1 after processing of the consistency correction structure 8 are stored on the host computer 10 , and the diagram is drawn on the host computer 10 ; as shown in FIG. 6 , a saturation output voltage of the design circuit is 3.3V, and response curves of output voltages after processing of the consistency correction structure 8 are great in dispersion and are also not wide in linearity range.
[0035] S2: carrying out linear fitting on the response curves of the voltages v1 1 [1:8], v1 2 [1: 8], v1 3 [1: 8], . . . ,v1 20 [1: 8] output by the 20 photodiodes after processing of the consistency correction structure 8 , which are obtained in the step S1, and then calculating slope vectors K[1:20] and intercept vectors B[1:20] of 20 response straight lines after fitting, as shown in Table 1:
[0000]
TABLE 1
Slope
K[1]
K[2]
K[3]
K[4]
K[5]
K[6]
K[7]
K[8]
K[9]
K[10]
0.067
0.070
0.068
0.064
0.071
0.069
0.072
0.069
0.073
0.067
Slope
K[11]
K[12]
K[13]
K[14]
K[15]
K[16]
K[17]
K[18]
K[19]
K[20]
0.072
0.067
0.066
0.069
0.070
0.073
0.072
0.069
0.071
0.072
Intercept
B[1]
B[2]
B[3]
B[4]
B[5]
B[6]
B[7]
B[8]
B[9]
B[10]
0.537
0.497
0.450
0.274
0.340
0.563
0.458
0.416
0.447
0.323
Intercept
B[11]
B[12]
B[13]
B[14]
B[15]
B[16]
B[17]
B[18]
B[19]
B[20]
0.540
0.415
0.330
0.373
0.445
0.541
0.520
0.551
0.525
0.566
[0036] Suppose that according to design of the consistency correction structure 8 , the D/A conversion circuit in the bias correction circuit 6 reads corresponding correction data vectors b[1:20] of the bias correction circuit 6 from the storage 9 , and converts the correction data vectors b[1:20] into corresponding correction vectors C[1:20] of the bias correction circuit 6 , and a conversion formula is:
[0000] C[i]= 0.00343 a[i]+ 0.191 i= 1,2, . . . 20 (5)
[0037] The gain correction circuit 7 reads corresponding correction data vectors a[1:20] of the gain correction circuit 7 from the storage 9 , and converts the correction data vectors a[1:20] into corresponding correction vectors A[1:20] of the gain correction circuit 7 , and a conversion formula is:
[0000] A[i]= 0.16 b[i]+ 0.156 i= 1,2, . . . 20 (6)
[0038] By the formulas (3), (4), (5) and (6), 40 constant coefficient vectors P[1:20] and Q[1:20] can be calculated, as shown in Table 2:
[0000]
TABLE 2
P[1]
P[2]
P [3]
P [4]
P [5]
P [6]
P [7]
P [8]
P [9]
P [10]
0.0135
0.0142
0.0136
0.0129
0.0144
0.0140
0.0146
0.0139
0.0146
0.0135
P [11]
P [12]
P [13]
P [14]
P [15]
P [16]
P [17]
P [18]
P [19]
P [20]
0.0145
0.0136
0.0133
0.0139
0.0142
0.0146
0.0146
0.0139
0.0144
0.0146
Q[1]
Q [2]
Q [3]
Q [4]
Q [5]
Q [6]
Q [7]
Q [8]
Q [9]
Q [10]
1.7487
1.4874
1.1798
0.0245
0.4604
1.9195
1.2310
0.9584
1.1602
0.3482
Q [11]
Q [12]
Q [13]
Q [14]
Q [15]
Q [16]
Q [17]
Q [18]
Q [19]
Q [20]
1.7682
0.9531
0.3942
0.6744
1.1487
1.7778
1.6409
1.8422
1.6708
1.9376
[0039] S3: selecting a tenth response straight line from 20 response straight lines obtained in the step S 2 as a target response straight line, fitting the other 19 response straight lines to the target response straight line, and calculating, by the host computer 10 , correction data vectors a 2 [1: 20] of the gain correction circuit 7 and correction data vectors b 2[1: 20 ] of the bias correction circuit 6 after fitting, as shown in Table 3:
[0000]
TABLE 3
a 2 [1]
a 2 [2]
a 2 [3]
a 2 [4]
a 2 [5]
a 2 [6]
a 2 [7]
a 2 [8]
a 2 [9]
a 2 [10]
19
17
19
21
17
18
16
18
16
19
a 2 [11]
a 2 [12]
a 2 [13]
a 2 [14]
a 2 [15]
a 2 [16]
a 2 [17]
a 2 [18]
a 2 [19]
a 2 [20]
16
19
20
18
17
16
16
18
17
16
b 2 [1]
b 2 [2]
b 2 [3]
b 2 [4]
b 2 [5]
b 2 [6]
b 2 [7]
b 2 [8]
b 2 [9]
b 2 [10]
24
25
25
31
28
24
25
25
25
29
b 2 [11]
b 2 [12]
b 2 [13]
b 2 [14]
b 2 [15]
b 2 [16]
b 2 [17]
b 2 [18]
b 2 [19]
b 2 [20]
24
25
28
26
25
24
24
24
24
24
[0040] S4: by the host computer 10 , inputting the correction data vectors a 2 [1: 20] of the gain correction circuit 7 and the correction data vectors b 2 [1: 20] of the bias correction circuit 6 , which are obtained in the step S3, into the consistency correction structure 8 through the storage 9 , then regulating the bias current of the light source 1 into an intermediate value I 4 , and simultaneously recording voltage values v2 1 [4], v2 2 [4], v2 3 [4], . . . , v2 20 [4] output by the 20 photodiodes under the bias current of the light source 1 , as shown in Table 4:
[0000]
TABLE 4
v2 1 [4]
v2 2 [4]
v2 3 [4]
v2 4 [4]
v2 5 [4]
v2 6 [4]
v2 7 [4]
v2 8 [4]
v2 9 [4]
v2 10 [4]
1.40
1.40
1.35
1.33
1.35
1.45
1.35
1.31
1.36
1.33
v2 11 [4]
v2 12 [4]
v2 13 [4]
v2 14 [4]
v2 15 [4]
v2 16 [4]
v2 17 [4]
v2 18 [4]
v2 19 [4]
v2 20 [4]
1.40
1.30
1.31
1.31
1.34
1.42
1.38
1.42
1.38
1.42
[0041] S5: carrying out averaging on the voltage values v2 1 [4], v2 2 [4], v2 3 [4], . . . , v2 20 [4] in the step S4 to obtain an average value of 1.37, then only regulating the correction data vectors b 2 [1: 20] of the bias correction circuit 6 , translating the response straight lines of the output voltages after processing of the consistency correction structure 8 towards the position of the average value of 1.37, and according to the formulas (4) and (5), calculating, by the host computer 10 , a group of new correction data vectors b 3 [1: 20] of bias correction circuit 6 , as shown in Table 5:
[0000]
TABLE 5
b 3 [1]
b 3 [2]
b 3 [3]
b 3 [4]
b 3 [5]
b 3 [6]
b 3 [7]
b 3 [8]
b 3 [9]
b 3 [10]
24
25
26
33
29
22
26
27
26
31
b 3 [11]
b 3 [12]
b 3 [13]
b 3 [14]
b 3 [15]
b 3 [16]
b 3 [17]
b 3 [18]
b 3 [19]
b 3 [20]
24
27
30
28
26
23
24
23
23
22
[0042] S6: repeating the step S4 and the step S5 until the dispersions of the response straight lines of the output voltages meet requirements. The 20 translated response straight lines are as shown in FIG. 7 . Then correction data vectors b 4 [1: n] of the bias correction circuit 6 are obtained, as shown in Table 6:
[0000]
TABLE 6
b 4 [1]
b 4 [2]
b 4 [3]
b 4 [4]
b 4 [5]
b 4 [6]
b 4 [7]
b 4 [8]
b 4 [9]
b 4 [10]
24
25
26
32
29
22
26
27
26
31
b 4 [11]
b 4 [12]
b 4 [13]
b 4 [14]
b 4 [15]
b 4 [16]
b 4 [17]
b 4 [18]
b 4 [19]
b 4 [20]
24
27
30
28
27
23
24
23
23
23
[0043] S7: carrying out linearity range expansion on the response straight lines of the output voltages, which are obtained in the step S6, so as to meet an input range requirement of a subsequent analog-digital collector, slightly increasing each value in the correction data vectors a 2 [1: 20] of the gain correction circuit 7 , and slightly reducing each value of the correction data vectors b 4 [1: 20] of the bias correction circuit 6 , so as to obtain new correction data vectors a 3 [1: 20] of the gain correction circuit 7 and new correction data vectors b 5 [1: 20] of the bias correction circuit 6 , as shown in Table 7:
[0000]
TABLE 7
a 3 [1]
a 3 [2]
a 3 [3]
a 3 [4]
a 3 [5]
a 3 [6]
a 3 [7]
a 3 [8]
a 3 [9]
a 3 [10]
29
27
29
31
27
28
26
28
26
29
a 3 [11]
a 3 [12]
a 3 [13]
a 3 [14]
a 3 [15]
a 3 [16]
a 3 [17]
a 3 [18]
a 3 [19]
a 3 [20]
26
29
30
28
27
26
26
28
27
26
b 5 [1]
b 5 [2]
b 5 [3]
b 5 [4]
b 5 [5]
b 5 [6]
b 5 [7]
b 5 [8]
b 5 [9]
b 5 [10]
17
18
19
25
22
15
19
20
19
24
b 5 [11]
b 5 [12]
b 5 [13]
b 5 [14]
b 5 [15]
b 5 [16]
b 5 [17]
b 5 [18]
b 5 [19]
b 5 [20]
17
20
23
21
20
16
17
16
16
16
[0044] S8: by the host computer 10 , transmitting the correction data vectors a 3 [1: 20] of the gain correction circuit 7 and the correction data vectors b 5 [1: 20] of the bias correction circuit 6 to the gain correction circuit 7 and the bias correction circuit 6 through the storage 9 , detecting whether the linearity ranges of the response straight lines of the output voltages meet requirements at the moment; as shown in FIG. 8 , the linearity ranges of the response straight lines of the output voltages are obviously improved compared to those in FIG. 6 .
[0045] S9: detecting whether the dispersions of the response straight lines of the output voltages at the moment meet requirements, and if no, by the host computer 10 , respectively inputting two groups of new initial correction data a 3 [1: 20] and b 5 [1: 20] to the correction data vectors of the gain correction circuit 7 and the correction data vectors of the bias correction circuit 6 , and repeatedly executing the steps S1 to S9 until the dispersions and the linearity ranges of the response straight lines of the output voltages after processing of the consistency correction structure 8 meet the requirements. Finally, correction data vectors a 4 [1: 20] of the gain correction circuit 7 and correction data vectors b 6 [1: 20] of the bias correction circuit 6 are obtained, as shown in Table 8.
[0000]
TABLE 8
a 4 [1]
a 4 [2]
a 4 [3]
a 4 [4]
a 4 [5]
a 4 [6]
a 4 [7]
a 4 [8]
a 4 [9]
a 4 [10]
33
31
33
36
30
31
30
32
29
34
a 4 [11]
a 4 [12]
a 4 [13]
a 4 [14]
a 4 [15]
a 4 [16]
a 4 [17]
a 4 [18]
a 4 [19]
a 4 [20]
30
32
29
34
30
33
34
32
31
30
b 6 [1]
b 6 [2]
b 6 [3]
b 6 [4]
b 6 [5]
b 6 [6]
b 6 [7]
b 6 [8]
b 6 [9]
b 6 [10]
14
15
17
23
20
14
16
18
17
21
b 6 [11]
b 6 [12]
b 6 [13]
b 6 [14]
b 6 [15]
b 6 [16]
b 6 [17]
b 6 [18]
b 6 [19]
b 6 [20]
13
18
22
19
17
13
14
14
14
13 | An absolute-type linear encoder absolute signal consistency correction method, related to the field of absolute-type linear encoder measurements, for solving the problem of narrow linear range for photoelectric responses and large signal dispersion found in an existing consistency correction method for a photoelectric conversion component and a processing circuit thereof. The correction method allows for enhanced absolute signal quality and increased system measurement precision. | 6 |
CROSS-REFERENCE
This invention relates to and claim priority from U.S. provisional patent application No. 61/450,374, filed Mar. 8, 2011, entitled PLASTIC OVERMOLDED WHEEL-BALANCING WEIGHT, which is incorporated herein by reference in its entirety. Furthermore, the disclosure of the priority provisional application is contained in the Appendix hereto, which is incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to a method for covering and protecting a steel wheel-balancing weight. More precisely, the present invention relates to polymer-covered wheel-balancing weights, a method for manufacturing same and a mold for manufacturing same.
BACKGROUND OF THE INVENTION
Wheel-balancing weights (or wheel weights, wheel balance weights) are commonly used on wheeled vehicles to improve the static and dynamic balancing of the wheel assembly. To balance the wheels, each wheel is rotated with a wheel-balancing apparatus that analyses and detects uneven weight distribution thereof that could generate significant vibrations when the wheels rotate at various rotating speeds. This undesirable wheel vibration would be transmitted to the entire vehicle, if not corrected. Corrective wheel-balancing weights, when required, are secured on the circumference of the wheel on both the interior and the exterior sides of the wheel. The addition of required wheel-balancing weights corrects the polar weight distribution of the wheel assembly and balances the wheel that will rotate without inducing undesirable vibrations.
Legacy wheel-balancing weights are made in lead. Nowadays, environmental consciousness and regulations suggest avoiding using lead that could have an undesirable effect on our ecosystems. Replacement of lead by steel is therefore a desirable direction.
However, the use of steel has some drawbacks. Steel is subject to corrosion and should be protected thereagainst. Steel balancing weights can also damage the wheel it is installed on. Steel is also harder and more difficult to shape to obtain a close and precise fit between the wheel-balancing weight and the wheel it is secured thereto. Additionally, the aesthetic of steel wheel balancing weights is questionable and it might be desirable to add a more visually attractive cover.
Covering the wheel-balancing weights with plastic could be an advantageous alternative. However, molding plastic over the wheel-balancing weight requires a complex and expansive tooling. Issues can arise when overmolding a steel wheel balancing weight. For instance, the overmolding plastic can retract and leave a gap with the steel weight where water and dirt can enter. Some overmolding materials might difficultly manage frequent changes in temperature and react poorly to impacts thereon. The geometry of the plastic overmolding might also require complex and expansive molds and handling.
The junction between the overmolding material and the wheel-securing clip is a sensitive portion of the overmolded wheel-balancing weight because the overmolding material boundary merges with the wheel-securing clip generally made of a different material.
Therefore, there exists a need in the art for an improved method, system and apparatus for covering wheel-balancing weights with plastic, polymer or another material. There is a need in the art for such a method, system and apparatus for covering wheel-balancing weights with overmolding polymer or another material that can be easily installed, economically manufactured and operated. And there is a very perceptible need for an improved fit between a polymer-covered wheel-balancing weight and a method of manufacturing same over the existing art.
SUMMARY OF THE INVENTION
It is one aspect of the present invention to alleviate one or more of the drawbacks of the background art by addressing one or more of the existing needs in the art.
Accordingly, at least one embodiment of the invention provides an undercutless overmolded wheel-balancing weight, a mold for producing same and a method of overmolding a steel wheel-balancing weight adapted to prevent injecting overmolding material in the region of the overhanging wheel-securing clip.
At least one embodiment of the invention provides a method of overmolding a metallic wheel-balancing weight using a mold that prevents polymer injection around the wheel-securing clip that would create an undercut interfering with the ejection of the overmolded wheel-balancing weight from the mold and require a more complex mold adapted to manage overhanging portions.
At least one embodiment of the invention provides a method and an apparatus for overmolding a steel wheel-balancing weight with a polymer wherein the distribution of polymer around the wheel-balancing weight allows extraction of the overmolded wheel-balancing weight by simply opening the apparatus in two.
At least one embodiment of the invention provides a method and a mold for overmolding a wheel-balancing weight with a polymer wherein the distribution of polymer around the wheel-balancing weight allows extraction of the overmolded wheel-balancing weight by opening the mold in two along the longitudinal plan of the wheel-balancing weight.
At least one embodiment of the invention provides ribs disposed on the longitudinal sides of the overmolded wheel-balancing weight that help maintains the wheel-balancing weight on one halve of the mold to facilitate extraction of the overmolded wheel-balancing weight when opening the mold in two halves along the longitudinal plan of the wheel-balancing weight.
At least one embodiment of the invention provides a method and an apparatus for overmolding a wheel-balancing weight with a polymer wherein the distribution of polymer around the clip of the wheel-balancing weight allows extraction of the overmolded wheel-balancing weight by opening the mold in two halves along the longitudinal plan of the wheel-balancing weight.
At least one embodiment of the invention provides a method and an apparatus for overmolding a wheel-balancing weight with a polymer wherein the clip of the wheel-balancing weight substantially follows the shape of the overmolding polymer.
At least one embodiment of the invention provides a method and an apparatus for overmolding a wheel-balancing weight with a polymer wherein the clip of the wheel-balancing weight substantially angularly extends from the overmolded polymer to offer a tight polymer-clip junction.
At least one embodiment of the invention provides a method and an apparatus for overmolding a wheel-balancing weight with a polymer-free wheel-balancing weight clip area.
At least one embodiment of the invention provides a method and an apparatus for overmolding a wheel-balancing weight while preventing polymer to be injected around the clip that would prevent removal from the mold by opening the mold in two.
At least one embodiment of the invention provides a method and an apparatus for overmolding a wheel-balancing weight that uses the wheel-securing clip of the wheel-balancing weight for restricting the injection of polymer around the wheel-securing clip.
At least one embodiment of the invention provides a method and an apparatus for overmolding a wheel-balancing weight that reduces the thickness of the overmolding material in the area surrounding the wheel-securing clip of the wheel-balancing weight.
At least one embodiment of the invention provides a polymer overmolded wheel-balancing weight that has no undercuts created by the overhanging wheel-securing clip assembled thereto.
At least one embodiment of the invention provides a polymer overmolded wheel-balancing weight having no polymer within the cavity defined by the wheel-securing clip and a method of manufacturing same.
At least one embodiment of the invention provides a polymer overmolded wheel-balancing weight wherein the overmolding material follows the shape of the wheel-securing clip of the wheel-balancing weight that substantially define the shape of at least a portion of the overmolding polymer.
At least one embodiment of the invention provides a polymer overmolded wheel-balancing weight wherein an edge of the overmolding material radially meet the wheel securing clip of the wheel-balancing weight.
At least one embodiment of the invention provides a wheel-securing clip configured to secure a wheel-balancing weight to a wheel, wherein the wheel-securing clip includes a raised portion adapted to improve the junction between an edge of the overmolding material and the wheel-securing clip.
At least one embodiment of the invention provides a polymer overmolded wheel-balancing weight wherein the wheel-securing clip of the wheel-balancing weight substantially contacts the injection mold and forms an injection boundary portion of the injection mold.
At least one embodiment of the invention provides a polymer overmolded wheel-balancing weight having a shape adapted to substantially match the circumference of the wheel secured thereto.
At least one embodiment of the invention provides an overmolded wheel-balancing weight wherein the weight is secured to the wheel-securing clip on the side opposed to the wheel-side when the overmolded wheel-balancing weight is secured to a wheel.
At least one embodiment of the invention provides an overmolded wheel-balancing weight that connects the weight to the wheel-securing clip via a protrusion formed in the weight; the protrusion being adapted to be compressed and/or riveted to secure the wheel-securing clip therewith.
At least one embodiment of the invention provides a wheel-securing clip for securing an overmolded wheel-balancing weight to a wheel that includes a recessed weight-securing portion sized and designed to receive therein material from a compressed protrusion protruding from the weight.
At least one embodiment of the invention provides a method of manufacturing an overmolded wheel-balancing weight, wherein the wheel-securing clip is used to locate the wheel-balancing weight in the mold; the wheel-balancing weight being preferably secured on the fixed portion of the mold.
At least one embodiment of the invention provides a method of manufacturing an overmolded wheel-balancing weight, wherein the wheel-balancing weight is secured in the mold with a clip-securing member adapted to pull the wheel-balancing weight with a moveable side of the mold.
At least one embodiment of the invention provides a method of manufacturing an overmolded wheel-balancing weight, wherein the overmolding material and/or the wheel-balancing weight is preheated to prevent expedite solidification of the injected overmolding material.
At least one embodiment of the invention provides a method of manufacturing an overmolded wheel-balancing weight, wherein the overmolding material is injected nearby the wheel-securing clip to equally distribute the overmolding material in the injection cavity of the injection mold.
At least one embodiment of the invention provides a colored polymer overmolded wheel-balancing weight adapted to substantially match the color of the wheel it is secured to.
At least one embodiment of the invention provides a kit of colored overmolded wheel-balancing weights wherein colors are adapted to distinguish wheel-balancing weights different having different weights.
At least one embodiment of the invention provides an injection mold including at least one retractable stem therein adapted to locate the weight in the injection mold during the injection of the overmolding material in the injection chamber, the at least one retractable stem being further adapted to be retractable during the injection process to allow complete overmolding of the weight, the at least one retractable stem also being adapted to be extended to locate and eject the overmolded wheel-balancing weight from the injection mold.
At least one embodiment of the invention provides a polymer (or plastic) weight (e.g. steel less weight) supported by a wheel-securing clip, the polymer weight being molded with the wheel-securing weight, the polymer weight being desirable for lightweight wheel-balancing masses that do not require a metallic weight.
At least one embodiment of the invention provides an overmolded wheel-balancing weight comprising a wheel-securing clip adapted to be secured to a wheel, a weight assembled to the wheel-securing clip and overmolding material adapted to at least partially cover the weight to protect the weight, wherein at least a portion of the wheel-securing clip is an overmolding material boundary.
At least one embodiment of the invention provides a method of manufacturing an overmolded wheel-balancing weight, the method comprising opening an injection cavity of an injection mold; securing the wheel-securing clip to a clip-supporting member in the mold to locate a weight in the injection cavity; closing the injection mold with a weight in the injection cavity; injecting overmolding material in the injection cavity to overmold at least a portion of the weight; opening the mold; and extracting the overmolded wheel-balancing weight from the mold.
At least one embodiment of the invention provides a plastic wheel-balancing weight adapted to be removably secured to a wheel to correct an unbalanced wheel to prevent undesired vibrations when the wheel is rotating, the plastic wheel-balancing weight comprising a wheel-securing clip sized and designed to be resiliently secured to a wheel; and a steel weight assembled to the wheel-securing clip and at least partially covered with plastic, at least a portion of the plastic being shaped by the wheel-securing clip.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
Additional and/or alternative advantages and salient features of the invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, disclose preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings which form a part of this original disclosure:
FIG. 1 is a top plan view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 2 is a flow chart illustrating a series of steps to produce an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 3 is a flow chart illustrating a series of steps to produce an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 4 is an almost front elevational view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 5 is a front elevational view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 6 is a top plan view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 7 is a rear sectional elevational view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 8 is a front sectional elevational view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 9 is a transversal isometric sectional elevational view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 10 is a transversal sectional elevational view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 11 is an isometric view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 12 is a transversal sectional view of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 13 is an isometric view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 14 is a transversal sectional elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 15 is a transversal sectional elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 16 is left side elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 17 is a transversal sectional elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 18 is a transversal sectional elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 19 is a transversal sectional elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 20 is a transversal sectional elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 21 is a transversal sectional elevational view of a wheel-securing clip in accordance with at least one embodiment of the invention;
FIG. 22 is a transversal sectional elevational view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 23 is a transversal sectional elevational view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 24 is a transversal sectional elevational view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 25 is a transversal sectional elevational view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 26 is a transversal sectional elevational view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 27 is a transversal sectional elevational view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 28 is a transversal sectional elevational view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 29 is an isometric view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 30 is an isometric view of a wheel-securing clip and a weight of an overmolded wheel-balancing weight in accordance with at least one embodiment of the invention;
FIG. 31 is an isometric view of a portion of an injection mold in accordance with at least one embodiment of the invention;
FIG. 32 is a side elevation view of a portion of an injection mold in accordance with at least one embodiment of the invention;
FIG. 33 is an isometric view of a portion of an injection mold in accordance with at least one embodiment of the invention;
FIG. 34 is an illustrative flow chart of an exemplary series of steps in accordance with at least one embodiment of the invention; and
FIG. 35 is an illustrative flow chart of an exemplary series of steps in accordance with at least one embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Embodiments of the present invention are described bellow with reference to the appended Figures. An exemplary overmolded metallic wheel-balancing weight 10 is illustrated in FIG. 1 . The wheel-balancing weight 10 defines, for the purpose of the following description, at least two illustrative plans thereof. A longitudinal plan 14 disposed along the longitudinal direction of the wheel-balancing weight 10 and a transversal plan 18 orthogonally intersecting the longitudinal direction of the wheel-balancing weight 10 . It is understood that the present invention can be completely or partially applied to a variety of wheel-balancing weights 10 having various sizes and shapes.
The illustrative wheel-balancing weight 10 depicted in FIG. 1 is overmolded with an polymer overmolding material such as polyethylene and polypropylene. The overmolding material 22 overmolds and protects the steel weight 26 therein against, inter alia, water, corrosion, dust and other debris encountered on the road. The overmolding material also servers to protect the wheel form the wheel-balancing weight 10 during installation on the wheel and when the wheel-balancing weight 10 is installed on the wheel under normal road use. Additionally, the overmolding material is used to improve the aesthetic appearance of the wheel-balancing weight and be used to visually differentiate different weights.
A wheel-securing clip 30 is secured to the overmolded steel weight 26 to removably secure the wheel-balancing weight 10 to the periphery of a wheel (not shown). An optional hole 34 is performed in the wheel-securing clip 30 in some embodiments to adjust the clipping force of the wheel-securing clip 30 on the wheel, provide a grip to remove the wheel-balancing weight 10 from the wheel and/or reduce the weight of the wheel-balancing weight 10 . The hole 34 is also used in some embodiments of the manufacturing process to handle the wheel-balancing weight 10 as it is going to be further explained below. Radiuses 38 , or chamfers 38 , are provided on ends corners of the wheel-securing clip 30 to prevent creating stress concentrators in the overmolded polymer that could result in rupturing the overmolded polymer and create cracks therein. The radiuses 38 , or chamfers 38 also help prevent damaging the wheel with sharp edges if used without overmolding. Embodiments of the present invention includes a reduced thickness portion 42 of the overmolded material 22 , in the neighborhood of the wheel-securing clip 30 , to prevent interferences between the overmolding material 22 and the wheel-securing clip 30 . The portion 42 thus facilitate proper connection between the wheel-securing clip 30 and the wheel and prevents any overmolding material 22 to be injected within the cavity defined by the wheel-securing clip 30 that would render harder the ejection of the wheel-balancing weight 10 from the mold. We will return later to the manufacturing aspects of the wheel-balancing weight 10 after some details concerning process embodiments for manufacturing the wheel-balancing weight 10 .
FIG. 2 illustrates an exemplary series of manufacturing steps adapted to produce a wheel-balancing weight 10 . An unmolded steel weight 26 is provided from raw material, preferably in the shape of a steel rod 50 , a steel wire 50 , or similar monolithic steel weight 26 adapted to improve wheel balancing. The raw steel rod is cut 54 and the length of the cut portion of steel rod 50 is determined by the desired weight of the wheel-balancing weight 10 . The total mass of the wheel-balancing weight 10 is equal to the added weight of the wheel-securing clip 30 , the steel weight 26 and the overmolding material 22 . The longer the portion of cut steel rod 50 is, the heavier the wheel-balancing weight 10 is going to be. Chamfers or radiuses are optionally performed 58 on each end of the steel weight 26 to remove undesirable sharp edges. The steel weight 26 is then stamped 62 to create therein a fastening protrusion 128 and an optional opposed compressed portion 140 that will be described in details below. The steel weight 26 is optionally plated after it has been chamfered and/or bent to improve, inter alia, its corrosion resistance 66 . A wheel-securing clip 30 is assembled 70 with the corresponding fastening protrusion and the wheel-securing clip 30 is secured to the steel weight 26 by compressing and deforming the fastening protrusion 74 to secure the wheel-securing clip 30 to the steel weight 26 . The assembled wheel-balancing weight 10 is then bent 78 to match the radius of the wheel it is going to be assembled to. The steps above are for illustrative purposes and can be reordered without departing from the scope of the present application.
FIG. 3 illustrates another exemplary series of steps for manufacturing polymer-overmolded wheel-balancing weights 10 in accordance with embodiments of the invention. An unmolded wheel-securing clip 30 and steel weight 26 assembly is inserted in an injection mold 90 . The mold is closed 94 to define a volume therein (e.g. injection chamber) for injecting a polymer, a resin, a thermoset plastic, a plastic or another suitable overmolding material around the unmolded wheel-securing clip 30 and steel weight 26 assembly. The connection between the wheel-securing clip 30 and the mold could be used to locate the steel weight 26 inside the mold. Polymers, such as polypropylene and polyethylene, could be used in the process. A precise fit is provided between the mold and the wheel-securing clip 30 to prevent any injection of plastic at undesired locations around the wheel-securing clip 30 . The mold interface with the wheel-securing clip 30 is designed in embodiments of the invention to prevent any undercuts that would interfere with the ejection of the molded wheel-balancing weight 10 with a mold having two halves and a single longitudinal parting line. Polymer is injected 98 in the mold and the injected plastic is cooled 102 prior to opening the mold 106 and extracting 110 the overmolded wheel-balancing weight from the mold.
FIG. 4 through FIG. 10 refer to an exemplary embodiment of the invention. More precisely FIG. 4 through FIG. 6 depict the exterior of the wheel-balancing weight 10 where it is possible to see the polymer overmolding 22 , the parting line 120 , and the wheel-securing clip 30 extending outside the polymer overmolding 22 .
FIG. 7 and FIG. 8 respectively illustrate longitudinal sectional views of the wheel-balancing weight 10 where one can appreciate a compressed portion 124 in the steel weight 26 from which extends the fastening protrusion 128 . The fastening protrusion 128 is assembled with a corresponding opening 132 located in the clip 30 . The illustrated assembly secures the wheel-securing clip 30 with the steel weight 26 by bending or compressing the fastening protrusion 128 when the wheel-securing clip 30 is assembled thereto. It can also be appreciated from these Figures that the steel weight 26 of the wheel-balancing weight 10 is curved along a radius 136 . The optional opposite compressed portion 140 can be appreciated on the other side of the steel weight 26 illustrated in FIG. 8 . The opposite compressed portion 140 helps to ensure proper pressure is put on the steel weight 26 at the stamping phase to create the fastening protrusion and also increases the strength of the steel weight 26 by locally hardening the material. The material of the protrusion 128 is adapted to be housed by a recessed portion 188 of the wheel-securing clip 30 that will be detailed later below.
Turning now to FIG. 9 where the fastening protrusion 128 assembly with the corresponding opening 132 located in the clip 30 is illustrated with more details. From this figure it can be appreciated that the mold (visible schematically illustrated in FIG. 10 ) design circumscribes the clip 30 and that results in no plastic injection within the clip 30 cavity 144 . Further, the shape of the clip 30 defines a radius 148 that retains the injected plastic on its proximal side 156 when the plastic is injected and abuts the plastic portion of the wheel-balancing weight 10 when the wheel-balancing weight 10 is overmolded. This layout allows overmolding the fastening protrusion 128 and the assembly with the clip 30 with plastic thus improving its corrosion resistance while reducing the risk of damaging the wheel when the wheel-balancing weight 10 is assembled to the wheel. FIG. 10 illustrates an exemplary mold having two halves 160 , 164 circumventing the wheel-securing clip 30 while defining a closed volume around the steel weight 26 to receive injected plastic therein. It can be appreciated that the shape of the mold's halves 160 , 164 is adapted to use the wheel-securing clip 30 as a mold boundary and thus prevent plastic to be injected too far within the cavity defined by the clip 30 . This is one way to ensure there is no undercut in the molding that would prevent extraction of the molded part 10 from a mold having two halves 160 , 164 and opening in the longitudinal plan 14 of the wheel-balancing weight 10 . In an alternate embodiment, the clip 30 can be completely free of plastic. Plastic is injected all around the clip 30 and even leaves the region of the clip that is connected with steel weight 26 free of plastic. Conversely, it could be advantageous to cover the connecting region between the clip 30 and the steel weight 26 with plastic to further prevent corrosion.
Moving now to FIG. 11 and FIG. 12 illustrating another embodiment of the invention. One can appreciate from FIG. 11 that the clip 30 has a different radius 148 causing the clip 30 to protrude almost perpendicular from the plastic molding 22 . As best seen in FIG. 12 , the present assembly allows sufficient distance 152 between the clip 30 and the polymer overmolding 22 to insert therein a portion of the mold adapted to mate with the clip 30 and prevent plastic injection around the clip 30 that would prevent a two halves 160 , 164 mold to be opened in the longitudinal plane 14 and the wheel-balancing weight 10 to be easily extracted from the mold. In the present situation, a schematic two-halves 160 , 164 mold with a single longitudinal opening therein has been drafted showing that the wheel-balancing weight 10 can be ejected from the mold that opens in two according to arrows 170 .
FIG. 13 illustrates a wheel-securing clip 30 equipped with a barb 174 adapted to further secure the wheel-securing clip 30 to a wheel by providing additional gripping to the wheel. The barb 174 of the present embodiment provides a second spring clamping 180 for gripping the wheel in addition to the first spring clamping 184 provided by the main body of the wheel-securing clip 30 . The shape of the wheel-securing clip 30 is adapted to engage the side of a wheel and is also adapted to be secured to the steel weight 26 . The interface between the wheel-securing clip 30 and the steel weight 26 has generally been described above. The wheel-securing clip 30 illustrated in FIG. 13 is provided with a recessed portion 188 sized and designed to receive therein material from the compressed fastening protrusion 128 (not illustrated in FIG. 13 ) engaging the opening 132 in the wheel-securing clip 30 . The opening 132 can be round or have a different shape adapted to prevent relative rotation of the two parts. The recessed portion 188 would preferably be deep enough to receive therein the material from the compressed fastening protrusion 128 so that it does not extend above the surrounding surface 192 . This helps reduce the required thickness of overmolding material 22 (not illustrated on FIG. 13 ) over the “riveted” assembly of the wheel-securing clip 30 and the steel weight 26 .
Another aspect of the wheel-securing clip 30 illustrated in FIG. 13 is the recessed position of the surface 192 provided by a projecting portion 196 included in the design of the wheel-securing clip 30 . The projecting portion 196 is embodied as a curved portion 200 in the present example. The curved portion 200 defined in the wheel-securing clip 30 locate the surface 192 deeper so that the overmolding material 22 can meet the curved portion 200 in a way to produce an efficient junction. This can be better understood by comparing a wheel-securing clip 30 having no projecting portion 196 , in FIG. 14 , and the wheel-securing clip 30 of FIG. 13 illustrated from the side in FIG. 15 . One can appreciate that the curved portion 200 provides a junction area 204 adapted to abut the overmolding material 22 that is schematically represented in FIG. 15 . The junction area 204 created by the curved portion 200 defined in the projecting portion 196 is adapted to abut the overmolding material 22 . The curved portion 200 can be used as an extension of the mold and is used to further define the volume defined by the mold. The curved portion 200 provides a more “radial” junction surface with the overmolding material 22 . This prevents having a very thin layer of overmolding material 22 joining the wheel-securing clip 30 that could easily wave or curve and leaves an opening for dirt and water to enter between the overmolding material 22 and the wheel-securing clip 30 . In some embodiments, the desired thickness 208 of overmolding material 22 over the surrounding surface 192 can dictate the height of the curved portion 200 therefore many different designs are possible to serve different needs. A second junction area 212 is provided on the opposite side and preferably provides a surface that can substantially radially abuts the overmolding material 22 . As it can be appreciated, a whole portion 216 of the wheel-securing clip 30 is used to contain the overmolding material 22 .
FIG. 16 through FIG. 21 illustrate a series of embodiments including wheel-securing clips 30 having different shapes adapted to be secured to different shape of wheels and adapted to cooperate with various metallic weights 26 . For example, the embodiments illustrated in FIG. 13 , FIG. 15 , FIG. 17 , FIG. 18 and FIG. 20 respectively have a flat clip portion 220 . FIG. 19 illustrates an embodiment including an angled flat clip portion 224 .
Turning now to FIG. 22 through FIG. 25 illustrating a series of sectional embodied wheel-balancing weights 10 . In these embodiments the steel weight 26 is assembled to the wheel-securing clip 30 but the fastening protrusion 128 is not shown compressed. From these embodiments one can appreciate the distribution of the overmolding material 22 over the steel weight 26 . The contact locations 230 between the steel weight 26 and the wheel-securing clip 30 is clearly shown for each embodiment. FIG. 22 illustrate en embodiment corresponding to the wheel-securing clip 30 of FIG. 14 that does not include a deporting portion 196 . The embodiments shown in FIG. 15 through FIG. 27 include the deporting portion 196 that allows an additional thickness 208 of overmolding material 22 . It can be appreciated from FIG. 23 through FIG. 27 that the combination of the deporting portion 196 and the recessed portion 188 of the wheel-securing clip 30 create a sequence of three combined curves 234 (or combined angled portions). A portion of a stamping 46 , or a shape/letters/information, defined in the overmolding material 22 can also be seen in these figures.
Referring to FIG. 22 , the steel weight 26 is provided with flat, or planar, contact portions 238 adapted to provide a suitable contact interface with the wheel-securing clip 30 . Radiuses 242 are provided on the metallic weights 26 to substantially match the curvature of the clip 148 in some embodiments and also provide a space where overmolding material 22 can be injected between the wheel-securing clip 30 and the metallic-weight 26 .
The wheel-securing clip 30 is secured to the steel weight 26 via the interface provided between the fastening protrusion 128 engagement with the opening 132 provided in the wheel-securing clip 30 . The fastening protrusion 126 is compressed 250 to protrude and extend 254 over the recessed portion 188 of the wheel-securing clip 30 as it can be appreciated in FIG. 28 , FIG. 29 and FIG. 30 . This assembly ensures that the wheel-securing clip 30 is permanently secured to the steel weight 26 to create a unitary wheel-balancing weight 10 .
The overmolded-wheel balancing weight 10 of embodiments of the invention is manufactured with an injection process. The injection process uses a mold 270 including a fixed portion 274 and a movable portion 278 that can be appreciated in FIG. 31 through FIG. 33 . The wheel-securing clip 30 and steel weight 26 assembly is positioned in the mold 270 prior to injecting the polymer in the mold 270 . The wheel-securing clip 30 and steel weight 26 assembly is located in the mold 270 by hooking the wheel-securing clip 30 to a clip supporting member 282 when the mold 270 is open. The wheel-securing clip 30 is preferably self-positioned by contacting the clip supporting member 282 at a plurality of locations. In the embodiment exemplified in FIG. 32 , the end 286 of the wheel-securing clip 30 contacts the upper side 290 of the clip supporting member 282 while a lower portion 216 of the wheel-securing clip 30 contacts the lower side 294 of the clip supporting member 282 . Further, the end 286 of the wheel-securing clip 30 is contacting a vertical edge 298 of the mold 270 to ensure not lateral movement is allowed. The clip-supporting member 282 of the illustrated embodiment is defined in the fixed portion 274 of the mold 270 with a clip-receiving cavity 302 included in the mold 270 . The clip-receiving cavity 302 is prolonging a clip-retaining member cavity 306 in the movable portion 278 of the mold 270 from which extends a movable clip-retaining member 310 that will be discussed below in details.
The wheel-securing clip 30 is temporarily secured in the mold 270 when the movable portion 278 of the mold 270 is closed onto the fixed portion 274 by applying a pressure on the wheel-securing clip 30 with a clip mating edge 314 . With that configuration, the wheel-securing clip 30 and steel weight 26 assembly is positioned such that the wheel-securing clip 30 is firmly secured in the closed mold 270 and the steel weight 26 is suspended in the injection cavity 318 of the mold 270 . Injection of the overmolded material is preferably made symmetrically in the injection cavity 318 . In the illustrated embodiment, the injection is made through a central injection port 322 to ensure equal distribution of the injection material 22 in the injection cavity 318 . Alternatively, the injection could be made by a plurality of injection ports (not illustrated) that would also equally distribute the injection material 22 in the injection cavity 318 . The steel weight 26 can be preheated prior to be placed in the injection cavity 318 to help prevent expedited solidification of the injection material 22 by cooling too fast the injection material 22 in the mold 270 such that the injection material 22 doesn't have time to fill completely the injection cavity 318 before solidification. Another way to help prevent early solidification of the injection material 22 is to preheat the injection material 22 in the circuit bringing the injection material 22 in the mold 270 to increase the time before the injection material 22 begins solidification. Positioning stems 338 (visible in FIG. 33 ) are provided in the mold 270 to help locate properly the steel weight 26 in the injection cavity 318 . These positioning stems 338 are adapted to be axially movable for contacting the metallic weight 22 when the mold 270 is closed and ensure proper positioning of the metallic weight 22 . The positioning stems 338 are adapted to be retracted as some point during the injection process when the overmolding material 22 begins to flow in the injection cavity 318 . The positioning stems 338 becomes optional when the overmolding material 22 is injected in the injection cavity 318 because the overmolding material 22 stabilizes the steel weight 26 in the injection cavity 318 . The injection of the overmolding material 22 is completed when the positioning stems 338 are retracted to ensure an even finish of the overmolding material 22 . The stems 338 are extended again, in an embodiment of the invention, when the mold 270 opens to stabilize and eject the overmolded wheel-balancing weight 10 from the mold 270 .
The movable clip-retaining member 310 is engaging the hole 34 included on the upper side of the wheel-securing clip 30 when the mold 270 is closing. The movable clip-retaining member 310 extends from the clip-retaining cavity 306 in the movable portion 278 of the mold 270 . The clip-retaining cavity 306 is sized and designed to allow sufficient vertical movements 326 to allow engagement of the hook 330 with the hole 34 . A corresponding opening 334 is included in the fixed portion 274 of the mold 270 . The corresponding opening 334 is configured to receive therein the movable clip-retaining member 310 and also to push the movable clip-retaining member 310 downward so that the hook 330 engages in the hole 34 of the wheel-securing clip 30 and cannot disengage when the mold 270 is closed. The movable clip-retaining member 310 is used to pull the overmolded wheel-balancing weight 10 from the fixed portion 274 of the mold 270 as it can be seen in FIG. 33 . Once the overmolded wheel-balancing weight 10 pulled from the fixed portion 274 of the mold 270 the movable clip-retaining member 310 is moved upward to disengage the movable clip-retaining member 310 from the hole 34 of the wheel-securing clip 30 .
Referring now more precisely to FIG. 33 , the illustrated overmolded wheel-balancing weight 10 has no overmolding material 22 in the neighborhood of the wheel-securing clip 30 to better see the assembled overmolded wheel-balancing weight 10 and also to illustrate one embodiment of the invention. In contrast, the junction of the wheel-securing clip 30 with the steel weight 26 is covered in other embodiments discussed above.
FIG. 34 illustrates an exemplary sequence of steps that can be used to overmold a wheel-balancing weight 10 . The mold 270 opens 350 , the steel weight 26 is heated 354 to prevent early solidification of the overmolding material 22 , The wheel-securing clip 30 is secured 358 in the mold 270 , the mold is closed 362 and the wheel-securing clip 30 is secured in the mold 270 , the polymer, or the overmolding material, is heated 366 prior to be injected in the mold 270 , the polymer is injected 370 in the mold 270 and solidifies, the mold 270 opens 374 to extract the overmolded wheel-balancing weight 10 therefrom 374 , the hook 330 from the movable clip-retaining member 310 is released 378 from the wheel-securing clip 30 and finally the overmolded wheel-balancing weight 10 is released 382 from the mold 270 .
Similarly, FIG. 35 illustrates another alternate sequence of steps adapted to embody embodiments of the invention. The wheel-securing clip 30 is used to locate 390 the unmolded steel weight 26 in the mold 270 , The mold 270 is closed and the hook 330 engages 394 the wheel-securing clip 30 , the overmolding material is heated 398 prior to being injected in the mold 270 , the overmolding material 22 is injected in the mold's injection cavity 318 , the locating stems 338 are retracted 406 during injection of the overmolding material 22 in the injection cavity 318 , the injection stops 410 , the mold 270 opens 414 and the overmolded wheel-balancing weight 10 is extracted 418 from the mold 270 .
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments and elements, but, to the contrary, is intended to cover various modifications, combinations of features, equivalent arrangements, and equivalent elements included within the spirit and scope of the appended claims. Furthermore, the dimensions of limiting, and the size of the components therein can vary from the size that may be portrayed in the figures herein. Thus, it is intended that the present invention covers the modifications and variations of the invention, provided they come within the scope of the appended claims and their equivalents. | A plastic wheel-balancing weight adapted to be removably secured to a wheel to correct an unbalanced wheel to prevent undesired vibrations when the wheel is rotating, the plastic wheel-balancing weight comprising a wheel-securing clip sized and designed to be resiliently secured to a wheel, and a steel weight assembled to the wheel-securing clip and at least partially covered with plastic, at least a portion of the plastic being shaped by the wheel-securing clip. An overmolded wheel-balancing weight comprising a wheel-securing clip adapted to be secured to a wheel, a weight assembled to the wheel-securing clip and overmolding material adapted to at least partially cover the weight to protect the weight, wherein at least a portion of the wheel-securing clip is an overmolding material boundary. A method of manufacturing same and a mold thereof is also provided. | 1 |
RELATED APPLICATIONS
[0001] This application is relates to U.S. Ser. No. 10/628,636 entitled Secure Trash Container, the contents of which are incorporated herein in their entirety.
FIELD OF THE INVENTION
[0002] This invention relates generally to plastic containers, and more specifically, to a plastic trash container assembly utilizing injection molded structural panels having integrally formed connectors. The trash container assembly is capable of being packaged and shipped in a knocked-down state and assembled into a decorative trash container without tools or additional fasteners.
BACKGROUND INFORMATION
[0003] Refuse or trash containers are a necessity for homeowners and business owners alike. Trash containers are preferably positioned in convenient locations for trash collection, which necessitates a decorative exterior if placed in close proximity to employees at businesses or residents in homes. A common form of trash container comprises a rigid one piece body which forms an internal chamber with an access opening provided within a rim at the upper end of the internal chamber. A lid is generally connectable with the rim to close the access opening. When the lid is removed, trash is able to be thrown into and collected within the trash container. Most modern trash containers also house a separate, removable waste receiving receptacle such as a collapsible plastic bag or liner. A common form of trash liner is a flexible plastic bag which is held open by folding an upper edge of the bag over the lip of the container facilitating the ability to place trash into the bag. Once the bag is filled, the top of the bag is tied closed and lifted out of the container.
[0004] For example, U.S. Pat. No. 5,803,300 discloses a rigid one-piece trash container with a bag holding mechanism which firmly supports a flexible walled plastic liner in an open configuration within the container. One drawback associated with this type of container occurs when the filled liner engages the side walls of the container. This engagement often causes difficulty in removing the filled bags from the container.
[0005] U.S. Pat. No. 5,390,818 discloses a trash receptacle for receiving and holding a flexible, collapsible trash liner. More particularly, the trash receptacle device provides a cavity formed in the lower portion of the trash receptacle for use as a foothold for assisting a user in removing a full trash liner from the receptacle, and a handhold to assist the user in transporting the receptacle.
[0006] Typically, the aforementioned one-piece containers are large and incapable of being knocked-down for shipping and storage, adding additional expense to the producer and thus the consumer. In an effort to reduce these problems, one piece containers generally include tapered side walls which allow them to be shipped in a nested arrangement. However, the nested containers are bulky and heavy, offering marginal gains to an end consumer.
[0007] In an attempt to overcome the shipping and storage problems associated with one-piece containers, containers capable of being shipped in a broken down condition have been provided. The top portion of these containers is usually provided with one or more openings, sometimes closed with a swinging door, through which the refuse may pass to be received by the waste receptacle within the container. The swinging doors are generally provided with a weight, spring, or mechanical mechanism which must be pushed open to place trash in the container. Because the top portion is securely attached to the container portion, these devices are generally constructed with access doors in their side to facilitate removing a filled trash liner from the container portion.
[0008] For example, U.S. Pat. No. 6,241,115 discloses a container for housing a waste receptacle. The device includes a base member formed by joining two identical halves. Two interchangeable side walls are attached to the base member and include extensions which form the top of the container. Interchangeable front and back walls are provided, the front wall being hingedly attached and acting as a door. The front and back walls include a spring loaded door for providing access to the waste receptacle. If a waste receptacle in the form of a plastic bag is used, a frame is provided. The frame is moveably mounted on tracks carried by the side walls of the container.
[0009] U.S. Pat. No. 5,348,222 discloses a pedal operated garbage container with improved access to the interior when the lid is opened. In this container, a platform for supporting waste is pivoted to the opposite side walls at its forward edge, and a front wall extends upwardly from the forward edge of the platform. Operation of a pedal pivots the platform upwardly and the front wall outwardly, providing access to the interior. One or more waste receptacles are placed on the platform, and must be lifted out for emptying as needed.
[0010] These types of containers suffer from numerous drawbacks for consumers. One such drawback relates to assembly of the container. These containers are often difficult to assemble, requiring tools and a substantial number of fasteners to align the panels and doors for proper operation. In addition, such containers may require internal linkages for operation of the lid.
[0011] Other advances in the art are aimed at making filled trash liners easier to remove from the receptacle. For example, U.S. Pat. No. 4,923,080 discloses a trash receptacle that opens on the side so that a filled liner need not be lifted out of the receptacle.
[0012] U.S. Pat. No. 5,984,134 discloses a trash container formed with an open fronted housing having a pivotally mounted front wall movable between a closed position and an open position to allow a filled liner to be removed from the housing. A releasable locking device locks the front wall into the closed position.
[0013] Typically, the structure of such devices are complex, requiring numerous small metal and/or plastic fasteners and connector members to maintain a structurally sound container. Due to the complexity of these devices they are generally only offered to consumers fully assembled and not in a knocked-down condition, and therefore require large shipping containers or crates, thereby increasing the final cost of the product to the consumer.
[0014] Such prior art devices, while working well, have not met all of the needs of manufacturers to provide a product that can be easily manufactured, packaged and shipped to the consumer in a knocked-down state. Nor have they met the needs of consumers requiring structural integrity combined with a pleasing aesthetic appearance and ease of assembly without the need for tools and small fasteners for assembly.
[0015] Paramount among such needs is a trash container panel system which creates a trash container having walls which resist panel separation, buckling, racking and weather infiltration. Structural integrity is a further consideration; the container formed by the panels must tie into the cover and bottom in such a way as to unify the entire enclosure. Also, from a safety standpoint, a cover should be present which can be easily latched and which provides dependable pivoting access to the lineable container.
[0016] There are also commercial considerations that must be satisfied by any viable trash container assembly; considerations which are not entirely satisfied by state of the art products. The trash container must be formed of relatively few component parts that are inexpensive to manufacture by conventional techniques. The trash container must also be capable of being packaged and shipped in a knocked-down state for assembly on a desired site.
[0017] Finally, there are ergonomic needs that a trash container assembly must satisfy in order to achieve acceptance by the end user. The trash container must be easily and quickly assembled using minimal hardware and requiring a minimal number or no tools. Further, the trash container must not require excessive strength to assemble or include heavy component parts. Moreover, the trash container must assemble together in such a way so as not to detract from the internal storage volume of the resulting trash container.
BRIEF DESCRIPTION OF THE INVENTION
[0018] The present invention provides a plurality of injection molded plastic panels having integrated connectors which are capable of being packaged and shipped in a knocked-down state and constructed to form an aesthetically pleasing trash container. The integrated connection of the side wall, cover and bottom panel components simplifies trash container construction. The panels are formed of injection molded plastic to interlock with one another without the need for separate metal fasteners or connectors.
[0019] The system incorporates a minimum number of components by integrally forming the connectors into the injection molded panels which are snapped together without tools to complete the assembly. This construction eliminates the need for separate extruded or molded connectors or fasteners to assemble the trash container. Injection molding allows the panels to be formed with a single wall having integral cross-bracing, ribs and gussets for increased rigidity when compared to blow molded or rotationally molded containers. The same side wall and bottom panel components can be used to create a variety of trash containers, and the assembly of the trash container requires minimal hardware and a minimum number of hand tools. The bottom, front and back wall panels have integrally formed outwardly projecting bosses for interlocking cooperative engagement with the left and right side wall panels. The left and right side wall panels are constructed with integrally formed inwardly contoured sockets for interlocking cooperative engagement with the bosses on the edges of the base, front and back side wall panels. The engagement between the bosses and the sockets serve to rigidly connect the components together into a weather resistant trash container.
[0020] The system further includes a one-piece latching cover which is hingedly connected and latched into place after the front, back, side and bottom panels have been fully assembled. Each of the side panels include a removably attached retainer-ramp. The retainer-ramps are constructed and arranged to cooperate with the side panels to support a conventional plastic trash liner without the need for metal frames, arms or fasteners. In addition, the retainer-ramps permit the flexible liner to be retained completely inside of the trash container in contrast with the prior art which folds the liner over the rim of the container or over a metal frame to retain the liner in an open position. Still yet, the ramp portion of the retainer-ramps permit a filled liner to be easily pulled upwardly through the container opening without snagging or catching.
[0021] The lid panel is hingedly connected to removable and replaceable hinge inserts to provide an opening to place trash in the container. The lid is provided with a latch means constructed and arranged to allow the lid to be latched in a closed position to prevent wind or animals from opening the container. The removable and replaceable hinge inserts permit interchangeability in the event that a hinge should become damaged.
[0022] In addition to the integrally formed bosses constructed to cooperate with the side panels, the lower surface of the base panel includes integrally formed bosses constructed and arranged to cooperate with casters to allow easy movement of a loaded or unloaded trash container. The upper surface of the base panel includes a vent allowing filled trash liners to be easily removed by eliminating the vacuum caused within a container when a filled liner engages the side walls.
[0023] Accordingly, it is an objective of the present invention to provide a trash container assembly having panels with integrated connectors.
[0024] A further objective is to provide a trash container having panels with integrated connectors which accommodate injection molding plastic formation of the panel components for increased structural integrity.
[0025] Yet a further objective is to provide a trash container assembly in which the side walls, cover, and bottom panels are integrally interlocked without separate fasteners or connectors.
[0026] Another objective is to provide a trash container assembly constructed of modular panels having an aesthetically pleasing appearance.
[0027] Yet another objective is to provide a trash container assembly that is capable of being packaged and shipped in a knocked-down state and constructed into a secure enclosure upon a desired site.
[0028] Yet another objective is to provide a trash container assembly that includes removable and replaceable hinge components.
[0029] Still yet another objective is to provide a trash container assembly that retains a flexible liner completely inside of the container without requiring separate frames or fasteners for improved aesthetic appearance.
[0030] Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
[0031] FIG. 1 is a perspective view of the trash container of the instant invention;
[0032] FIG. 2 is an exploded view of the trash container shown in FIG. 1 ;
[0033] FIG. 3 is a perspective view of the trash container embodiment shown in FIG. 1 with a liner in place and the cover panel in the open position;
[0034] FIG. 4 is a front view of the trash container embodiment shown in FIG. 1 ;
[0035] FIG. 5 is a section view taken along line 1 - 1 of the embodiment shown in FIG. 4 illustrating the cooperative engagement of the base, side, and cover panels;
[0036] FIG. 6 is a partial section view taken along line 2 - 2 of the embodiment shown in FIG. 5 illustrating the cooperative engagement of the cover latch and the front panel;
[0037] FIG. 7 is a bottom view of the base panel utilized in the trash container embodiment shown in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0038] While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated.
[0039] FIGS. 1-2 which are now referenced illustrate perspective and exploded views of the trash container assembly, generally referenced as 10 , according to a preferred embodiment of the present invention. The trash container is made up of a base panel 100 , left side wall panel 200 , right side wall panel 300 , back wall panel 400 , front wall panel 500 and cover panel 600 . In the preferred embodiment the panels comprising the assembly are formed of but not limited to a suitable plastic such as polystyrene, polypropylene or polyethylene, through the process of injection molding. The result is that the panels comprising the trash container 10 are formed as unitary single wall panels with integral connectors and cross bracing. Strengthening ribs 202 and gussets 204 are formed within the inner surfaces of the wall panels, cover panel, and base panel in order to enhance rigidity of the panels while leaving the external surface in a generally smooth condition for aesthetic purposes, as shown in FIG. 2 . The base panel 100 has a top surface 104 , bottom surface 106 ( FIG. 7 ), front edge 108 , back edge 110 , left edge 112 , and right edge 114 . Integrally formed along the left and right base panel edges is a plurality of bosses 116 for attaching the base panel to the left 200 and right 300 wall panels. The bosses 116 extend outwardly from each edge to cooperate with sockets 210 extending inwardly along the bottom portions 206 , 306 of the left and right wall panels respectively. The bosses 116 and sockets 210 are constructed and arranged so that the bosses 116 enter and mateably engage the sockets 210 , securing the panels together in an inter-fitting engagement and perpendicular arrangement. Detent or spring-lock fasteners, such as those illustrated at 118 cooperate with apertures 208 , to secure the bosses 116 to the sockets 210 . Those skilled in the art will appreciate that the spring-lock fasteners 118 can be used throughout the trash container 10 to mount or secure components to one another, and to facilitate ready assembly of the trash container if it is provided in an unassembled or broken-down condition. The overlapping boss 116 and socket 210 arrangement increases the structural integrity of the trash container 10 by preventing the panels 200 , 300 , 400 , 500 from bowing or bending inwardly or outwardly, and thus, adversely affecting the appearance or operation of the trash container 10 .
[0040] The left wall panel 200 is configured having a first edge 212 and a second edge 214 . Both edges 212 , 214 include integrally formed elongated and contoured sockets 210 extending inwardly in a linear fashion along each edge. The sockets 210 are generally constructed and arranged to cooperate with the bosses 116 provided along either edge of the back panel 400 and front panel 500 .
[0041] The right wall panel 300 is configured having a first edge 312 and a second edge 314 . Both edges 312 , 314 include integrally formed elongated and contoured sockets 210 extending inwardly in a linear fashion along each edge. The sockets 210 are generally constructed and arranged to cooperate with bosses 116 provided along either edge of the back panel 400 and front panel 500 .
[0042] The outer surface of the panels 200 , 300 , 400 , 500 are constructed generally smooth having a plurality of inwardly bowed grooves 230 for added strength and aesthetic appearance. The inside of the panels 200 , 300 , 400 , 500 are constructed with a plurality of strengthening ribs 202 extending along the panels with a portion of the ribs 202 being provided with a plurality of gussets 204 to further strengthen the panels. The ribs 202 and gussets 204 increase the structural integrity of the trash container 10 by preventing the panels 200 , 300 , 400 , 500 from bowing or bending inwardly or outwardly, and thus, adversely affecting the appearance or operation of the trash container 10 . The integrally formed ribs 202 and gussets 204 are facilitated by injection molding. Injection molding offers significant strength and stability advantages over blow-molding or rotational molding as utilized in the prior art. In this manner the container of the instant invention is capable of handling a significant amount of weight as compared to prior art plastic trash containers.
[0043] The left and right side panels 200 , 300 are attached to the base panel 100 by inserting the contoured bosses 116 into the sockets 210 until the spring tabs 118 engage the apertures 208 in the sockets 210 of the left 200 and right 300 panels.
[0044] The front and back panels 400 , 500 are attached to the left 200 and right 300 panels by inserting the elongated and contoured bosses 116 into sockets 210 until the spring tabs 118 integrally formed into the contoured bosses 116 engage the apertures 208 in the sockets of the left and right panels 400 , 500 . It will be appreciated that the purpose of the contoured and elongated bosses 116 are to align two panels in a perpendicular relationship and to facilitate their mechanical connection. The perpendicular panels are brought into an overlapping relationship wherein the contoured bosses 116 enter the corresponding sockets 210 in the left, and right panels 200 , 300 respectively. The result is a mechanically secure connection between the panels. The overlapping edges between the panels as described above provides a secure connection and offers several advantages. First, the design allows the panels to be connected without the need for separate connectors. Second, the design creates a positive lock that prevents separation of the panels. Third, the design maintains alignment of the panels in the same plane and prevents bowing or bending of either panel relative to one another. The resultant trash container created by the combination of the interlocking panels benefits from high structural integrity and reliable operation.
[0045] Referring to FIGS. 3-6 , perspective and section views of the trash container are shown illustrating the pivotal operation of the cover panel 600 and latch assembly. Also illustrated is the construction and arrangement of the separable and replaceable hinge assemblies. The hinge assemblies generally include a pair of hinge inserts 650 ( FIG. 2 ), each having a pair of hinge pins 652 . The hinge pins are constructed and arranged to cooperate with a plurality of hinge pin receivers 602 . The hinge pin receivers 602 are generally a pair of outwardly depending supports 603 located adjacent to the back edge 610 of the cover panel 600 and are constructed and arranged to cooperate with a hinge pin 652 to allow pivotal movement of the cover panel 600 between an open position illustrated in FIG. 3 and a closed position illustrated in FIG. 1 . The hinge pins 652 are each integrally formed onto the upper portion of the hinge inserts 650 . The hinge pins 652 cooperate with their respective hinge pin receivers 602 to allow pivotal movement of the cover panel 600 and also allow the cover 600 to be removed when in the open position by lifting the cover upward and sliding the hinge pin receiver 602 outward from the pins 652 . The cover panel 600 is releasably secured in the closed position by pivoting the cover panel downward until the cover latch 622 pivotally mounted into the front panel 500 engages at least one corresponding indentation 620 formed in the front portion of the cover panel 600 . The result is a positive mechanical connection. To open the cover panel 600 , the cover latch 622 is pulled outward until the catch 624 is released from the indentation 620 and the cover panel is pivoted upwards. The result is a positive mechanical connection between the side walls of the container and the cover panel 600 that resists opening by winds or animals, and yet provides easy access for placing trash into the container.
[0046] It should be appreciated that the hinge assemblies allow the cover panel 600 to be installed and/or removed when the cover 600 is in the open position and yet the cover and lid are secure and non-removable when in the closed position. It should also be appreciated that the hinge inserts are removable and replaceable in the event that one or both should become damaged.
[0047] Referring to FIGS. 2-6 the retainer-ramps 450 are illustrated. The retainer-ramps include an upper portion 452 that is constructed and arranged to retain a flexible liner 700 in an open position within the trash container and a lower portion 454 constructed and arranged to permit a filled liner to be easily removed from the trash container without catching or snagging. The upper portion of the retainer-ramp includes a depending lip 456 over which the flexible liner may be folded over for retention thereof. The lowermost portion of retainer-ramp is constructed and arranged to fit against the inner surface of each respective panel and taper inwardly away from the inner surface as the retainer-ramp extends toward the container opening. In this manner the retainer-ramps function as a guide to aid in the removal of a filled liner from the container. The inner surface of the retainer-ramp 458 includes an attachment means integrally formed thereto for attaching the retainer-ramp to the inner surface of the front, back, left and right panels. The attachment means is illustrated herein as a pair of snap-lock connectors 460 . The snap-lock connectors each include an inner portion 462 and an outer portion 464 ; both portions are integrally formed onto their respective panels. For assembly the inner portion is pressed into the outer portion until the components are engaged. In addition to the retainer-ramps the base panel is provided with a vent aperture 120 to aid in the removal of filled liners.
[0048] Referring to FIGS. 2 and 7 , the casters 120 and caster bosses 122 are illustrated. The casters 120 include a stem 124 that is constructed and arranged to cooperate with an aperture 126 integrally formed onto the lower surface 106 of the base panel 100 . For assembly the stem is inserted into the boss aperture until retainer ring 128 snaps into a corresponding groove formed into the aperture, the result is a mechanically secure connection. The casters may also include a releasable lock 130 to prevent the trash container from unwanted movement on hills and the like.
[0049] All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
[0050] It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification.
[0051] One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims. | The present invention provides a plurality of injection molded plastic panels having integrated connectors which are capable of being packaged and shipped in a knocked-down state and constructed to form an aesthetically pleasing trash container. The integrated connection of the side wall, cover and bottom panel components simplifies trash container construction. The panels are formed of injection molded plastic to interlock with one another without the need for separate metal fasteners or connectors. The system incorporates a minimum number of components by integrally forming the connectors into the injection molded panels which are snapped together to complete the assembly. | 1 |
OBJECT OF THE INVENTION
The present invention refers to an electronic device intended for controlling the heating glow plugs in internal combustion engines of the diesel type.
The control performed by the glow plug controlling device also allows detection of failures which may be produced in glow plugs such as open circuit and short-circuit, which makes it a safety and control measure which, in the event these situations arise, prevents damage to the leads, connectors and the device itself.
BACKGROUND OF THE INVENTION
To perform the control function, electromechanical relays are being used which make it possible to stop current flow through the glow plug in the event a short-circuit is detected.
However, these electromechanical relays have a high response time, on the order of several milliseconds, so they are not able to open the circuit with the speed required, and damages due to overcurrents may occur in the few milliseconds in which the relay is still closed and the short-circuit exists.
Certain known control devices of this type already incorporate semiconductors to reduce the response time, such as those presented in U.S. Pat. Nos. 5,122,968 and 4,500,775 and German patents nos. 38.06.649 and 40.04.400.
In some of these known devices, the glow plugs are connected in parallel whether in groups or the entire set, making diagnosis of failures difficult precisely because of this connection.
DESCRIPTION OF THE INVENTION
With the heating glow plug controller for diesel engines, response times to minor short-circuits of under 1 millisecond are achieved, which removes any possibility of damages to the electrical system of the vehicle or to the device itself in the event of this type of accident.
This quick response in order to open the circuit is achieved by making the element performing this action be an electrical component with very short commutation times, which acts as an electronic relay, one of these elements existing per glow plug. The current flowing through each of these is probed, so that a short-circuit or open circuit may be detected, in which case a status line informs of the breakdown.
Each of the electronic relays consists of a power transistor performing the functions of the relay itself, and a set of electronic components for its control and failure detection.
The glow plug controller therefore consists of a set of electronic relays, one per glow plug existing in the engine; there may be any number of glow plugs depending on the number of cylinders, although the most common situation is four glow plugs for conventional passenger cars.
The set of electronic relays is connected to a calculator module which determines the need or not to connect the glow plugs and prepares the information for the breakdown diagnosis.
The glow plug controller is made of integrated electronic components in which the functions of control, diagnosis and power are carried out., allowing this device to be compact and easily handled, occupying a minimal space in the vehicle.
The controller which is the object of this invention has been designed to work with all presently existing models of heating glow plugs for diesel engines.
DESCRIPTION OF THE DRAWINGS
In order to complete the description being given and to aid a better understanding of the characteristics of the invention, attached to this descriptive memory and as an integral part of the same is a set of drawings in which with an illustrative and non-limiting nature the following is represented:
FIG. 1 shows a schematic representation of the set of relays which control the loads, together with the calculator block to which they are connected.
FIG. 2 is an internal block diagram of each of the electronic relays.
PREFERRED EMBODIMENT OF THE INVENTION
The glow plug controller basically consists of a set of relays ( 1 ) powered by the battery voltage (Vbatt), and is composed of individual electronic relays (T 1 -T 4 ), one for each glow plug or load (R 1 -R 4 ) existing, which close the circuit.
The set of relays ( 1 ) is connected to the calculator module ( 2 ) which may also be called the controller module since it can determine the need for connection of loads (R 1 -R 4 ) or not, in addition to preparing the information of breakdown diagnosis to make it visible to the driver or even to the repair garage.
Each of the electronic relays (T 1 -T 4 ) may be integrated in a semiconductor wafer or optionally, more than one or all may be integrated in a single integrated wafer.
The set of relays ( 1 ) form a block which is independent of the calculator module ( 2 ), each of them being located in a box and the two connected by connectors or leads, although as an option they could also be included in a single box forming a single block ( 3 ) in order to obtain a smaller sized device.
Also reaching the set of relays ( 1 ) is the control signal (in) from the calculator module ( 2 ), which is a low intensity logic signal which can control the status of the electronic relays (T 1 -T 4 ) and therefore the flow of the activation current through the loads or glow plugs (R 1 -R 4 ).
The set of relays ( 1 ) provides the diagnosis signal (status) which is a logic output signal triggered by a low level in this implementation of the invention, but which could be triggered by a high level in another embodiment of the same. This signal shows whether the glow plugs are working correctly or not or if there has been a breakdown in one of them, whether this be a short-circuit or an open circuit, in which case this diagnosis signal (status) will have a low level. This signal is sent to the calculator block ( 2 ) so that this block informs the driver of the vehicle of the breakdown status if this occurs.
In the preferred embodiment of the invention, a single control signal (in) and single diagnosis signal (status) are available, but as shown in FIG. 1, optionally a diagnosis signal (status) could be available for each of the electronic relays (T 1 -T 4 ) and even several diagnosis signal for each one, so that it may be known whether the breakdown in each of the glow plugs is caused by an open circuit or a short-circuit.
In FIG. 2 can be seen the internal circuit (T 1 ) of which each electronic relay consists (T 1 -T 4 ), where it is shown that the element which opens or closes each electronic relay (T 1 -T 4 ) is a transistor (Q), a MOSFET power transistor. Each of these transistors (Q) has its drain connected to the positive pole of the battery (Vbatt) and out of the source comes the output current (Iout i ) towards the corresponding load (R 1 -R 4 ) which is the rated working current for the glow plugs.
Two operational amplifiers are used as comparators, the short-circuit comparator (C 1 ) used to detect a short-circuit and the open circuit comparator (C 2 ) used to detect this breakdown.
For this reason the output current (Iout i ) is taken to the non inverting input of the comparator (C 1 ) where it is compared to a reference signal (U 1 ) connected to the inverting input. In a normal working status the reference signal (U 1 ) is greater than (Iout i ) so that at the comparator (C 1 ) output there is a low level, but when a short-circuit occurs (Iout i ) increases considerably, making the voltage at the non inverting input greater than that at the inverting one and therefore the short-circuit comparator (C 1 ) output produces a high level signal indicating the short-circuit status.
Similarly, to detect an open circuit failure current (Iout i ) is taken to the inverting input of the open circuit comparator (C 2 ) and the reference signal (U 2 ) is taken to the inverting input. In normal operation, the output of the comparator will be a low level, since the voltage produced by current (Iout i ) in this input is greater than the reference signal (U 2 ). In the event of a failure due to an open circuit, reference signal (U 2 ) will be greater than current (Iout i ) so that the output of the comparator will have a high level, indicating this failure.
The outputs of both comparators are taken to the inputs of a NOR logical gate, labeled (G) in FIG. 2; the output of this gate constitutes the diagnosis signal (status) of each electronic relay (T i ), or optionally the connection of all of these make up the general diagnosis (status) output for the set of relays ( 1 ).
In this way, the diagnosis signal (status) will be a high level in normal operation of the glow plugs, and shall become a low level whenever there is a failure in any of them due to an open circuit or a short-circuit, informing the calculator module ( 2 ) of this event.
The output of the short-circuit comparator (C 1 ) is also taken to the logic control block (L), which also receives the control input (in) common to all relays (T 1 -T 4 ). This logic control block (L) basically consists of a bi-stable, so that when this control input allows it, transistor (Q) is activated, making it conduct via the driver (D).
The output of the short-circuit comparator (C 1 ) interferes in the bi-stable, so that in the event of a short-circuit the control logic block (L) places transistor (Q) in the cut-off regime even if the control signal (in) is still active, and therefore stops current flow through the corresponding glow plug, to prevent damage to the electrical system and the semiconductor itself or any other component of the device.
The diagnosis signal (status) will thereby show a high level, i.e. will be inactive, while the glow plug corresponding to that signal has a current flow lower than an estimated upper current limit, so that a current greater than this limit shall be interpreted as a short-circuit, which will also transistor (Q) to be cut-off, and it will also be inactive while the current flow through the glow plug is above a certain estimated lower limit, so that a current below this limit is interpreted as an open circuit.
These upper and lower limits are set respectively by the reference signals (U 1 ) and (U 2 ), the value of which may vary for the different glow plug models depending on their manufacturing characteristics.
Driver (D) is needed to govern transistor (Q), since this is a power transistor requiring a high excitation voltage to be in the conducting regime. | The heating glow plug controller for diesel engines is capable of controlling the activation of the glow plugs and consists of a set of electronic relays which in addition can also detect failures due to open circuit or short-circuit, and then acting in under 1 millisecond since electronic relays are semiconductors and no electromechanical elements are involved. There is one electronic relay per glow plug and each one may consist of a separate semiconductor wafer or alternatively, several relays may be integrated in a single semiconductor wafer. The set of relays is in turn connected to controlling or calculating module, and may even be included in the same block as the calculator module or in a different one connected by connectors and leads to the calculator block. | 5 |
TECHNICAL FIELD
The present invention relates to a sheet of material such as paper (or the like) which is folded four times to create a thin pamphlet, or brochure, with front and back panels, and in particular with a spine in a T-shaped formation allowing the pamphlet or brochure to be easily visible when stored on a bookshelf.
BACKGROUND ART
Information such as advertising is frequently distributed in the form of a thin pamphlet or brochure. The disadvantage of disseminating information in this way is that when such a pamphlet is filed or stored on a bookshelf, it is difficult to notice or find the pamphlet amongst other books or files occupying the same shelf because the spine portion is thin and does not stand out for easy recognition.
Folders constructed from a single blank of material are already known in the art. Such a folder or binder is shown in U.S. Pat. No. 4,537,544, (Method of Forming A Folder For Reports or Statements of Account and Cover To Effect The Method). These folders are typically formed from a single sheet of material and adhesive is applied in the center spine portion so that papers may be fastened into place. Although such folders are useful for collectively and securely holding papers in place, they do not, however, provide an enhanced spine region specifically created to facilitate recognition of the folder amongst other materials on a book shelf.
Other folders and binders exist that are useful for holding papers in place according to various organizational needs. One such folder is shown in U.S. Pat. No. 4,284,227 (Expansion Folder With Accordian Pleat Backbone) where a file folder is constructed with a special type of spine that allows for expansion of the backbone in an accordion type fashion. The main purpose of this special feature is to allow for changes in the holding capacity of the folder so that varying quantities of papers can be efficiently stored.
Various other sorts of folders also exist: for example, those with specialized clasping mechanisms (U.S. Pat. No. 4,934,738: Combined Document Binder and Cover Holder), with special adhesive portions (U.S. Pat. No. 4,928,995: Bindable Cover Folders) and those specially constructed for particular contents (U.S. Pat. No. 5,407,230: Print Folder.) However, the spine has the same thickness as the contents in each of these devices.
Therefore, there has been a need for type of pamphlet or brochure with an enhanced spine region facilitating recognition of a thin pamphlet or brochure when it is filed or stored with other materials in a bookshelf.
SUMMARY OF THE INVENTION
The present invention provides a thin pamphlet or brochure with an enhanced spine region that allows it to be easily located on a bookshelf.
In a preferred embodiment of the invention, the special spine is essentially formed by four folds in the same single sheet of material that forms the brochure. First a central spine is formed by a central panel. On both sides of the central elongate panel, one more fold is created, creating a pair of connecting panels extending between the central panel and main front and back panels. The width of the connecting panels should not exceed one half of the width of the central panel. The connecting panels are folded inwardly toward the central panel in a position approximately parallel to the central panel. This results in the formation of a `T` shaped spine for the pamphlet. A pamphlet thus constructed could be preprinted and shipped flat.
In an alternative embodiment of the invention, additional pages are affixed into the pamphlet by adhering them to one of the edges of either the main front panel or the main back panel.
In an another alternative embodiment of the invention, additional pages are affixed into the pamphlet by adhering them into the spine of the pamphlet itself.
Thus, a brochure or pamphlet that is constructed according to the present invention supplies the brochure with an exaggerated spine region which can be labeled, thereby allowing the brochure to be easily recognized even when placed with other materials on a bookshelf.
Thus, it is an object of the present invention to provide a pamphlet or brochure, or cover, with an enhanced spine.
It is a further object of the present invention to provide a pamphlet or brochure, or cover, with an enhanced spine constructed from a single sheet of material.
It is a further object of the present invention to provide a pamphlet or brochure with an enhanced spine constructed from a single sheet of material, within which additional pages may be affixed.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a pictorial view of a pamphlet embodying the present invention, viewed from an angle so that the enhanced T-shaped spine is visible.
FIG. 2 is a plan view of the inside surface of a flat blank from which a pamphlet embodying the present invention is formed.
FIG. 3 is pictorial view of a pamphlet embodying the present invention, viewed with front and back panels open, showing relative sizes of spine in correlation to size of the panels.
FIG. 4 is a pictorial view of a pamphlet embodying the present invention with one additional page inserted by fixation onto the spine, and with both front and back panels closed.
FIG. 5 is a exaggerated top cross sectional view taken along line 4--4 of FIG. 1.
FIG. 6 is a exaggerated top cross sectional view showing an alternate embodiment including an internal page affixed along one of the main panels.
FIG. 7 is a exaggerated top cross sectional view taken along line 7--7 of FIG. 4, showing an alternate embodiment including an internal page affixed between one connecting panel and the spine.
FIG. 8 is a top view of the invention that shows the configuration of the pamphlet in a flat position suitable for shipment.
DETAILED DESCRIPTION
Referring now in more detail to the drawing, in which like numerals refer to like parts throughout the several views. FIG. 1 shows a pamphlet 10 embodying the present invention. A blank 26 for forming the pamphlet is shown in FIG. 2. An open view of the pamphlet 10 is shown in FIG. 3.
The pamphlet 10 preferably is constructed from a single sheet of paper, paperboard, plastic, or the like, forming the blank 26, the inside surface of which is viewed in FIG. 2. The blank 26 is rectangular, and defines a top edge 12 and a bottom edge 13. The pamphlet is formed by dividing the blank into various panels. An elongate central panel 11 is formed spanning the height of the blank from its top edge 12 to its bottom edge 13. A pair of fold lines or scores, 14 and 15, extend along the longitudinal edges of the central panel 11, and foldably connect the central panel to a front connecting panel 16 and a back connecting panel 17, respectively. The connecting panels 16 and 17 each have a width no more than half the width of the central panel 11, and preferably have a width approximately equal to half the width of the central panel.
A front main panel 21 and a back main panel 25 are foldably connected to the connecting panels 16 and 17 along fold lines or scores 18 and 19, respectively. The width of the main panels may be varied depending on the nature of the information to be presented.
Optionally, a strip of pressure-sensitive adhesive 30 may be provided along one or both of the main panels, for retaining additional sheets of paper or the like. In FIG. 2, a single strip of adhesive 30 is placed on the back main panel 25 immediately adjacent to the connecting panel 17. The adhesive may be the well-known releasable paper adhesive marketed by 3M Corporation.
In order to completely assemble the pamphlet 10 from the blank 26 four folds are required. For shipping purposes however, only three folds are necessary so that the pamphlet may be shipped flat. The front connecting panel 16 and front main panel 21 are folded about fold line 14 inwardly onto the central panel and lie approximately parallel thereto. The front main panel 21 is then folded about fold line 18 in a direction away from the central panel 11, until it rests on the outer surface of the front connecting panel 16. The back connecting panel 17 and back main panel 25 are then folded about fold line 15 inwardly onto the central panel and the front main panel 21. Following the three preceding folds, the pamphlet is flat as shown in FIG. 8, and is suitable for shipping. One more additional fold, of the back main panel 25 about the fold line or score 19 to a position approximately perpendicular to the central and connecting panels, results in the complete erection of the pamphlet. In the erected configuration, both connecting panels 16 and 17 are positioned approximately parallel to the central panel 11. It should be noted that the line 19 preferably is pre-folded or scored prior to shipment in the configuration of FIG. 8, to make the final fold easy for the user.
The configuration of the pamphlet following complete assembly and erection is such that the inside of both the front main panel 21 and the back main panel 25 are positioned face to face, with the connecting panels 16 and 17 folded almost flat against the inside surface of the central elongate panel 11 in a position approximately parallel to it. These panels form a T-shaped enhanced spine region 24, having the width of the central panel 11 even when the thickness of the main panels and any sheets placed therebetween is much smaller. For example, FIG. 5 shows a brochure 10 in which the main panels 21 and 25 are the only sheets of the brochure. Despite the lack of thickness of the main panels, when the brochure is inserted between other materials (shown in phantom in FIG. 5) on a bookshelf, the spine 24 will tend to remain perpendicular to the main panels. Thus, printed indicia on the central panel 11 will remain readable and the brochure will be easier to locate on the bookshelf.
In a modified embodiment shown in FIG. 6, an additional page 26 is added to the pamphlet by affixing it to the adhesive 30. It will be understood that the unitary piece 10 shown in FIGS. 1-3 may function as a cover to additional pages inserted within the main panels. A single additional sheet may be added, as shown in FIG. 6, or a bundle of sheets. When used as a cover, the unit 10 may advantageously be made of a thicker material, such as paperboard or plastic, to better protect the interior pages.
FIGS. 4 and 7 shows an alternate manner in which an additional page 27 may be added to the pamphlet by capturing it in the spine between the connecting panel 16 and the central panel 11. The additional page (or pages) may be secured by adhesive 31 either to the central panel 11 or one of the connecting panels, with an edge of the pages adjacent to the fold line between the central panel and a connecting panel. During assembly the additional pages 27 are folded with the panels as required, resulting in the configuration of FIG. 7 when the pages are attached adjacent to the fold line 14, to either the front connecting panel 16 or the central panel 11, or both.
Reference has been made to folding locations as fold lines or score lines. One skilled in the art would appreciate that score lines or pre-folding may provide ease of use, but are not always necessary to make a brochure or cover according to this invention. For example, when the invention is embodied in a paper brochure, conventional machinery may be able to fold the paper along the indicated fold lines without any pre-scoring or folding. Furthermore, the panels of an article embodying the invention may be foldably connected by hinges, and may themselves be made of rigid material.
It should also be noted that an enhanced spine can be provided, if desired, on only one side of the main panels. This would be accomplished by eliminating one of the connecting panels, such as the back connecting panel 17. The width of the remaining connecting panel could be adjusted depending on the thickness of any pages inserted between the main panels. The resulting configuration would be L-shaped rather than T-shaped as shown.
While this invention has been described in detail with particular reference to a preferred embodiment thereof, it will be understood that variations and modifications can be made without departing from the spirit and scope of the invention as described in the following claims: | A thin pamphlet or book cover, with a flat spine portion in a `T` configuration that is made from a single sheet of material folded four times. | 1 |
BACKGROUND
[0001] 1. Field
[0002] The invention relates to the field of electrical signals and more particularly, to the reflection of electrical signals along a circuit path.
[0003] 2. Background Information
[0004] Electrical circuits often have their operation driven by a signal which is known as a “clock” signal (which may also be called a “trigger” signal). The trigger signal typically takes the form of a pulse which rises from a first predetermined voltage level (typically called “low”) to a second predetermined voltage level (typically called “high”). Of course, the designation of which voltage level constitutes a “low” or “high” is merely a matter of convention. Circuits which receive a trigger signal typically have their operation triggered when the trigger signal crosses a “trigger” level. The trigger level is a voltage level between the first predetermined level and the second predetermined level. As the voltage of the trigger signal rises between these levels, it crosses the trigger level with the result that the circuit receiving the trigger signal may perform an operation. For example, the well known latching circuit may read in and store a signal on a data input terminal where the trigger signal crosses the trigger level. When this occurs, the latch circuit is said to have been “triggered” or “clocked”. Of course, a circuit's operation may also be triggered by the transition of the trigger signal from the higher predetermined voltage level to the lower predetermined voltage level. The transition of a trigger signal from low to high voltage levels may be referred to as a “rising” edge of a trigger signal. Likewise, the transition from high to low voltage levels of a trigger signal may be referred to as the “falling” edge.
[0005] Some circuits are capable of performing multiple operations, with some operations triggered on a rising edge and others triggered on the falling edge of a trigger signal. For example, a memory circuit may write (e.g. store) signals on its data input terminals and may read (e.g. output) signals stored in the memory to its data output terminals. The memory write operation may be triggered on the rising edge of a trigger signal and the memory read operation may be triggered on the falling edge of the trigger signal. Some memory circuits may be capable of performing a write operation and a read operation each triggered by the rising and falling edges of the same trigger signal.
[0006] In some situations it may be desirable to substantially delay the triggering of the operation on the rising edge, without causing substantial delay to the triggering of the operation on the falling edge, or vice versa. For example, it may be desirable to delay the triggering of a memory write operation on the rising edge of a clock pulse, without delaying the triggering of a memory read operation on the falling edge of the same trigger signal. This may be desirable when the signals on the data input terminals are not available at the point in time when the rising edge of the trigger signal triggers a memory write operation. The circuits which read data signals from the data output terminals of the memory may be configured to receive the data signals shortly after the same trigger signal triggers a memory read operation. Thus it may not be acceptable to simply delay the entire trigger signal to delay the rising edge, because by delaying the entire trigger signal, both the rising and falling edges are delayed, which interferes with the memory read operation. The circuit reading data signals from the memory would be forced to incur delays to accommodate the delays in the memory write operation.
[0007] One solution to this problem is to narrow the trigger signal so that the falling edge occurs sooner after the rising edge. By narrowing the trigger signal, the time at which the rising edge occurs may be delayed without altering the time in which the falling edge occurs. This approach may not be feasible in applications where the trigger signal is distributed to multiple circuits, some of which are adapted to expect the rising edge to occur at a predetermined point in time and at least one circuit adapted to expect the rising edge to be delayed. In this situation, simply adapting the trigger signal generator to produce a narrower trigger signal may be undesirable because the operation of some of the circuits receiving the trigger signal may be adversely affected. Those skilled in the art will recognize that the same situation could arise in situations where the timing of the rising edge is to be left unchanged, but where the falling edge needs to occur sooner in time.
[0008] Thus, there exists a continuing need for a mechanism by which the timing of one edge of a signal received by circuit may be adjusted without substantially changing the timing of the other edge of the signal, and without altering the timing of the signal edges to other circuits which receive the signal.
SUMMARY
[0009] An apparatus includes a circuit and a signal source to supply a trigger signal to the circuit. The signal source is adapted to supply the trigger signal such that a reflection of the trigger signal delays the time at which the circuit is triggered.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, may be further understood by reference to the following detailed description read with reference to the accompanying drawings.
[0011] [0011]FIG. 1 shows a system in accordance with one embodiment of the present invention.
[0012] [0012]FIG. 2 shows an embodiment of stud path in accordance with the present invention.
[0013] [0013]FIG. 3 illustrates an embodiment of an incident trigger signal in accordance with the present invention.
[0014] [0014]FIG. 4 is an illustration showing the trigger signal embodiment of FIG. 3 as it travels over a distance D.
[0015] [0015]FIG. 5 shows an embodiment of a composite signal produced in accordance with the present invention.
DETAILED DESCRIPTION
[0016] In one embodiment of the present invention an incident trigger signal and a reflected trigger signal are superimposed to form a composite trigger signal. Relative to the incident trigger signal, the rising edge of the composite trigger signal is delayed without creating substantial delay in the falling edge of the composite trigger signal. The following description and drawings describe the present invention in terms of specific embodiments and examples, however, the scope of the present invention is defined only by the amended claims.
[0017] [0017]FIG. 1 shows a system in accordance with one embodiment 100 of the present invention. The system comprises a processor 118 , a memory controller 102 , and a memory 104 . The processor 118 and memory controller 102 are coupled by way of processor bus 120 . Memory controller 102 and memory 104 are coupled by way of memory bus 1 10 . Processor 118 may write data to memory by placing data signals on processor bus 120 . Memory controller 102 may transfer these data signals to memory bus 110 , from which they may be received into memory 104 , e.g. written to memory 104 . Processor 118 may read data signals from memory 104 by indicating to memory controller 102 an address in the memory 104 from which to read data signals. Memory controller 102 may signal memory 104 to place data signals from this address on memory bus 110 . Memory controller 102 may transfer the data signals from memory bus 110 to processor bus 120 .
[0018] Embodiment 100 further comprises trigger signal generator 106 to generate synchronized trigger signals to memory controller 102 and memory 104 . Trigger signals serve to synchronize the operation of memory controller 102 and memory 104 . This is commonly referred to as a common clock circuit configuration. Trigger signals propagate from signal generator 106 to memory controller 102 over signal path 114 . Trigger signals propagate from signal generator 106 to memory 104 over signal path 116 . The trigger signal generated by signal generator 106 is referred to as the incident trigger signal. In accordance with one embodiment of the present invention, a junction 1 12 is formed on signal path 116 and signal path 108 is joined thereto. Signal path 108 will henceforth be referred to as stub path.
[0019] [0019]FIG. 2 shows an embodiment 200 of stud path 108 in accordance with the present invention. In this embodiment junction 112 is a simple “T” connection of stub path 108 and signal path 116 . Stud path is unterminated. That is, no resistive, capacitive, inductive, or other electrical load is coupled between stud path 108 and an electrical ground. Stud path 108 floats electrically and is may be a strip of conductive material of length D′ which is unterminated. Length D′ may be chosen to be approximately the same as the length D of signal path 116 as is present between junction 112 and memory 104 . Stud path length D′ may not be exactly equal to the length D, and may in fact fall within some percentage of length D. For example, length D′ may “of an order” of the length D. In some embodiments, stud path length D′ may vary between approximately 5% and 50% of the length of signal path 116 between junction 112 and memory 104 . Determination of stub length D is described further below.
[0020] [0020]FIG. 3 illustrates an embodiment 300 of an incident trigger signal in accordance with the present invention. Trigger signal 300 is illustrated in accordance with complimentary metal oxide semi-conductor technology (CMOS), which comprises a well known predetermined low voltage level of Vss and a predetermined high voltage level of Vdd (source and drain voltages respectively for CMOS transistors). Of course, other semiconductor technologies are equally applicable to the present invention. Trigger signal 300 is illustrated in terms of its voltage level over time. Trigger signal 300 comprises a rising edge 302 , a plateau 306 , and a falling edge 304 . Clock pulse 300 takes a certain period of time Tr to rise from low voltage level Vss to the high voltage level Vdd. This period of time may be referred to as the rise time of the leading edge 302 of trigger signal 300 .
[0021] [0021]FIG. 4 is an illustration showing the trigger signal embodiment of FIG. 3 as it travels over a distance D. Two distinct points in time are illustrated. At a first time t, the trigger signal 300 begins to rise from the low voltage Vss. At a later time t+Tr, the trigger signal 300 has reached plateau level 306 . During the time it took trigger signal 300 to rise from the low voltage level to the high voltage level, e.g. the rise time Tr, the trigger signal may propagate a distance D down signal path 116 . For example, a trigger signal with a ins (one nanosecond) rise time may propagate approximately five inches down the signal path 116 during the rise time. This distance may be calculated by multiplying ins by the speed of electrical signal propagation, which may vary according to the electrical properties of signal path 116 but which may, in some embodiments, approximate the well-known value of the speed of light. As previously described, the length D′ of stub path 108 need only be “of an order” or D and not precisely equal to D.
[0022] [0022]FIG. 5 shows an embodiment of a composite signal produced in accordance with the present invention. Stud path 108 may reflect an incident trigger signal 508 to produce a reflection signal 510 on signal path 116 . The length of stud path 108 is appropriately chosen is described previously. The rising and falling edges of reflection signal 510 may be offset from the rising and falling edges of the incident signal 508 .
[0023] Incident signal 508 and reflected signal 510 may superimpose over time to form a composite trigger signal 506 . Composite signal 506 may have several advantageous properties. A plateau 502 may be formed in rising edge of composite signal 510 . Plateau 502 serves to delay the attainment of voltage levels above the plateau level 502 . A plateau 504 may also be formed on falling edge of composite signal 506 , however, plateau 504 of falling edge may occur at a voltage level substantially below plateau 502 of rising edge. A circuit whose operation is driven by composite trigger signal 506 is adapted to be triggered at a voltage level above plateau level 502 . Triggering of the circuit's operation may thus be delayed, due to the rising edge delay in reaching voltage levels above the plateau level 502 . 042390 .P 7235
[0024] For example, consider a memory circuit with a memory write operation triggered by the rising edge of incident signal 508 at a trigger level of 0.5 volts. According to the signal timings illustrated in FIG. 5, said circuit may be triggered for write operation at approximately Ins and 1 Ins. Now consider a memory circuit with a write operation triggered at a 1 IV trigger level by composite signal 506 . The write operation of such a circuit will be triggered at approximately 2.5ns and 12.5ns.
[0025] Now consider a memory circuit with a memory read operation triggered by the falling edge of incident signal 508 at a trigger level of 0.5 volts. According to the signal timings illustrated in FIG. 5, said circuit may be triggered for read operation at approximately 6ns and 16ns. Now consider a memory circuit adapted to trigger a read operation at trigger level of 1 .IV by falling edge of composite signal 506 . The read operation of such a circuit will again be triggered at approximately 6ns and 16ns. In other words, the read operation of the two memory circuits is triggered at approximately the same time. In other words, by applying composite trigger signal 506 to a circuit with appropriately adapted trigger levels, the trigger time of an operation on the rising edge of composite trigger signal 506 may be substantially delayed without affecting the trigger time of an operation triggered on the falling edge of composite trigger signal 506 .
[0026] The invention is in no way limited to the use of stub paths to produce the composite signal 506 . Any mechanism for producing a trigger signal with the properties of composite signal 506 may also be employed. One embodiment employs a stub path 108 to produce a reflection signal 510 to combine with an incident signal 508 produced by a signal generator 106 . However, other embodiments could produce a signal with properties similar to those of composite signal 506 using an arrangement of transistors or other circuit components. Such embodiments could potentially employ reflection signals, but would not necessarily do so. From the perspective of the circuit being triggered by the composite signal 506 , the source (e.g. the specific circuit arrangements and adaptations) which produce composite signal 506 is less important than the properties of composite signal 506 itself. Thus, the invention is not limited to a particular circuit arrangement acting as the source of the composite signal 506 .
[0027] Returning to FIG. 1, a memory write operation triggered on the rising edge of a trigger signal could be substantially delayed by applying the present invention to signal path 116 and memory 104 . This may provide memory controller 102 with substantial additional time to establish data signals on memory bus 1 1 0 before the write operation is triggered. Trigger signals on other signal paths, for example path 114 , would not be affected. Furthermore, memory read operations triggered by the falling edge of the trigger signal would not be substantially delayed as a result of delaying the memory write operations. This may be advantageous in applications where more time is needed to set up the data on memory bus 110 for a write operation, without affecting the performance of a read operations, and without affecting the timing of trigger signals to other circuits supplied by signal generator 106 .
[0028] Those skilled in the art will of course recognize that the present invention may also be applied to delay circuit operations triggered on the falling edge of a signal. In such a case, the trigger level of the circuit for both rising and falling edge operations would be adjusted below the level of the plateau on the falling edge of composite signal 506 . Thus, operations triggered on the rising edge would not be substantially delayed, because they are triggered at levels less than the level of the rising edge plateau. Operations triggered on the falling edge might be substantially delayed because they are triggered at levels less than the level of the falling edge plateau.
[0029] While the invention has been described in terms of specific embodiments and examples, those skilled in the art will appreciate numerous modifications are possible which fall within the scope of the invention. The specific examples and embodiments described herein are presented for purposes of illustration only, and the scope of the present invention should be construed only in light of the claims which follow. | An apparatus includes a circuit and a signal source to supply a trigger signal to the circuit. The signal source is adapted to supply the trigger signal such that a reflection of the trigger signal delays the time at which the circuit is triggered. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a National Stage Application of International Application No. PCT/FR01/00265, filed Jan. 26, 2001. Further, the present application claims priority under 35 U.S.C. § 119 of French Patent Application No. 00 01094 filed on Jan. 28, 2000.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a protective helmet, and more specifically a device for adjusting the helmet adapted to promote its positioning and adjusting as well as its fitting to the size of the user's head.
2. Discussion of Background Information
Protective helmets have long been commonly used in various fields, whether for professional use as is the case for the military, plane or helicopter pilots, the police, or firefighters, or for civil or private use, as is the case for motorcycle riders, rally or race car drivers, or workers on a worksite.
These prior art helmets are generally formed of an external rigid shell and an inner liner adapted to allow the positioning of the helmet and to promote the comfort of the user. They can also comprise an inner envelope of a synthetic material adapted to dampen the impacts.
In these helmets, multiple types of adjustments are known to allow a precise positioning of the helmet and an adequate tightening of the tightening means in order to give optimum comfort to the one using the helmet. However, the prior art adjusting devices are not entirely satisfactory as they do not allow a sufficiently precise adjustment or require one to remove the helmet in order to carry out these adjustments. Additionally, they are generally complicated to implement and often require long and tedious handling.
Thus, the prior art adjusting devices present drawbacks related to their implementation, use and reliability. The object of the present invention is to overcome the aforementioned drawbacks through arrangements that are simple, reliable, easy to implement and inexpensive. The invention proposes a protective helmet whose adjustment device is easy to use, quick and precise so as to promote the fitting of the helmet to the size of the user's head.
SUMMARY OF THE INVENTION
According to its main characteristic, the protective helmet of the invention is of the type formed of a shell adapted to protect the user's head and comprising an inner lining that has a headband of adjustable size due to an adjusting device, and it is characterized in that the adjusting device has two gripping members adapted to be manually brought together or spread apart by the user in order to vary the size of the headband.
According to another characteristic of the protective helmet, the headband has a main band portion, two adjustment extensions that extend to the ends of the main band and bear the gripping arrangements, as well as a connecting element having locking arrangements adapted to cooperate with the adjustment extensions.
According to a complementary characteristic of the protective helmet, the cooperation between the adjustment extensions and the locking arrangements of the connecting element occurs by a rack system.
According to the preferred embodiment of the protective helmet of the invention, the headband is arranged on the inside of the helmet shell such that the connecting element is positioned at the rear of the helmet and that the gripping members are arranged substantially in the zone corresponding to the user's nape.
According to another characteristic of the protective helmet, it is characterized in that the gripping members are arranged at the end of the adjustment extensions and have a transverse support surface extending downwardly (BA) below the planes containing the main band and the adjustment extensions.
According to an additional characteristic of the protective helmet of the invention, it is characterized in that it comprises elastic biasing system arranged between the connecting element and the adjustment extensions or the band in order to bias the headband towards its loosened position against the locking arrangements.
According to the preferred embodiment of the protective helmet, the elastic biasing system is formed by two return arms connecting the adjustment extensions to the connecting element and which bias the extensions due to their specific elasticity.
According to another characteristic of the protective helmet of the invention, it is characterized in that the locking arrangement is constituted of two locking buckles that each comprise a locking lever bearing a locking projection adapted to cooperate with notches arranged on the external surface of the adjustment extensions and which each comprise an unlocking member.
According to a complementary characteristic of the protective helmet, it is characterized in that the adjustment extensions comprise at their end, at the level of their gripping members, a guiding pin adapted to guide the sliding of the adjustment extensions with respect to the locking arrangements of the connecting element by sliding each one in a guiding slot arranged in the connecting element.
Furthermore, it is noted that according to an alternative embodiment of the protective helmet, the gripping members are separated by a distance less than 15 centimeters.
The invention also provides for a protective helmet comprising a shell adapted to protect a user's head, an inner lining, a headband comprising an adjusting device. The adjusting device includes two gripping members adapted to be manually moved towards or away from one another by the user in order to vary a size of the headband.
The two gripping members may be adapted to be manually moved towards and away from one another by the user in order to vary a size of the headband. The headband may comprise a main band portion having two ends and an adjustment extension arranged at each end of the main band. Each adjustment extension may comprise one of the two gripping members. The headband may further comprise a connecting element. The connecting element may comprise a locking system adapted to cooperate with the adjustment extensions. The locking system may comprise two buckles each having a locking projection which engages notches of each adjustment extension. The locking system may comprise a rack system. The headband may be arranged on an inside of the shell. The headband may further comprise a connecting element positioned at a rear part of the helmet, and wherein the gripping members are arranged substantially in a zone corresponding to the user's nape. The headband may comprise a main band portion having two ends and an adjustment extension that is arranged at each end of the main band, whereby one gripping member is arranged on each adjustment extension. The headband may comprise a main band portion having two ends and an adjustment extension that is arranged at each end of the main band, whereby one gripping member is arranged on an end of each of the adjustment extensions.
Each gripping member may comprise a support surface that extends downwardly and transversely relative to a plane running through the headband. The headband may comprise a main band portion having two ends and an adjustment extension that is arranged at each end of the main band, whereby one gripping member is arranged on an end of each of the adjustment extensions. The main headband portion may be arranged on a first plane and the adjustment extensions may be arranged on a second plane, the first and second planes being parallel to one another and being spaced apart by a distance.
The protective helmet may further comprise an elastic biasing system acting to bias open the headband. The headband may comprise a main band portion having two ends, an adjustment extension that is arranged at each end of the main band, and a connecting element, whereby one gripping member is arranged on an end of each of the adjustment extensions. Each end of the main band portion may be connected to each adjustment extension and each adjustment extension may be connected to an end of the connecting element. The elastic biasing system may comprise arms which are connected to each adjustment extension in order to bias the headband towards a loosened position. The connecting element may comprise the elastic biasing system. The connecting element may comprise a system that locks each adjustment extension. The system that locks each adjustment extension may comprise two buckles each having a locking projection which engages notches in each adjustment extension. The system that locks each adjustment extension may comprise two buckles each having a locking lever and a projection which engages notches in each adjustment extension. The system that locks each adjustment extension may comprise two buckles each having an unlocking member, a locking lever, and a projection which engages notches in each adjustment extension. The elastic biasing system may comprise two return arms connecting the adjustment extensions to the connecting element, whereby the two return arms bias the adjustment extensions due to their specific elasticity.
The headband may comprise a main band portion having two ends, an adjustment extension that is arranged at each end of the main band, and a connecting element connected to each adjustment extension at two locations, whereby one gripping member is arranged on an end of each of the adjustment extensions. The headband may comprise a main band portion having two ends, an adjustment extension that is arranged at each end of the main band, and a connecting element connected to each adjustment extension. Each adjustment may comprise a guiding device adapted to slidingly engage the connecting element. Each guiding device may comprise a pin which engages a guiding slot in the connecting element. The connecting element may comprise a system that locks each adjustment extension, the system that locks each adjustment extension comprising two buckles each having a passage which allows the adjustment extension to slide within, an unlocking member, a locking lever, and a projection which engages notches in each adjustment extension.
The gripping members may be separated by a distance “d” of less than 15 centimeters when the headband is in a loosened position.
The invention also provides for a protective helmet having a shell that protects a user's head, an inner lining system, an adjustable headband system, wherein the adjusting headband system comprises a main headband portion having a first end and a second end. A first adjustment extension device is coupled to the first end. A second adjustment extension device is coupled to the second end. Each of the first and second adjustment extension devices comprises a gripping member. A connecting element is coupled to the each of the first and second adjustment extension devices. The connecting element comprises an elastic biasing system which causes the gripping members to be biased away from one another.
The invention also provides for a protective helmet having a shell that protects a user's head, an inner lining system, an adjustable headband system, wherein the adjusting headband system comprises a main headband portion having a first end and a second end. A first adjustment extension device is coupled to the first end. A second adjustment extension device is coupled to the second end. Each of the first and second adjustment extension devices comprises a gripping member. A connecting element has a portion that is non-movably coupled to each of the first and second adjustment extension devices. Each of the first and second adjustment extension devices is movably coupled to another portion of the connecting element. The connecting element comprises at least one of an elastic biasing system adapted to move the gripping members away from one another and a system that adjustably locks each adjustment extension at a number of positions.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics and advantages of the invention will become apparent from the following description, with reference to the attached drawings, which are given only as non-limiting examples.
FIGS. 1-11 show a preferred embodiment of the protective helmet of the invention and its adjusting device, wherein:
FIG. 1 is a perspective view of a protective helmet;
FIG. 2 is a perspective view of the inside of the protective helmet;
FIG. 3 is a perspective view of the headband and its adjusting device;
FIG. 4 is an exploded view of the headband and its adjusting device;
FIGS. 5 a - 5 c are rear views of the loosened position, the intermediary position and the tightened position of the headband;
FIGS. 6 a - 6 c are bottom views of the headband in the positions of FIGS. 5 a - 5 c , respectively;
FIG. 7 is a perspective view of the adjusting device;
FIGS. 8 a , 8 b , 8 c , 8 d show the housing of the adjusting device, in perspective and top views, and in cross-section along AA and CC, respectively;
FIG. 9 is a perspective view of the unlocking lever;
FIGS. 10 a and 10 b are a front view and a lateral view of the adjustment extensions and their gripping member;
FIG. 11 is a rear view of the middle connecting element on which the adjustment occurs; and
FIGS. 12 a and 12 b are views similar to FIG. 5 a , showing two alternative embodiments according to which the headband has arrangements that enable the symmetrical displacement of the ends of the headband.
DETAILED DESCRIPTION OF THE INVENTION
The protective helmet having the general reference numeral 1 is adapted to protect the user's head and can be of any type, i.e., a firefighter's helmet or a military helmet, for example, but also a helmet for a mountain climber, a bicyclist, or any other type of helmet, without leaving the scope of protection for the invention.
According to a preferred embodiment of the invention, it is a firefighter's helmet 1 as shown in FIGS. 1 and 2. It is constituted of an external shell 2 , advantageously made in one piece, that is adapted to surround the user's head, and of an inner lining 10 arranged on the inside of the shell to allow the positioning and the tightening thereof around the head. In particular, this lining 10 has a cap 4 formed of a flexible wall or a holding net 9 and a headband 5 whose size is adjustable due to an adjusting device 6 .
According to the preferred embodiment of the helmet 1 of the invention, the headband 5 is adapted to surround the user's head to promote the hold of the helmet once it is positioned. The adjusting device 6 thus allows varying the useful length of the headband 5 , i.e., its diameter. To this end, the adjusting device 6 of the invention comprises two gripping members 7 a and 7 b that are adapted to be manually actuated by the user in order to be spaced apart or brought together, their actuating allowing one to vary the diameter of the headband 5 . These gripping members 7 a , 7 b extend downwardly BA below the headband 5 , and more specifically, below the plane containing the lower edge of the headband so that they can be more easily gripped and actuated by the user when the helmet 1 is positioned on the head.
According to the preferred embodiment and as shown in FIGS. 3 and 4, the headband 5 is constituted by a main band portion 8 , two adjustment extensions 11 a and 11 b arranged at the free ends of the band 8 , a connecting element 12 and locking arrangements 13 born by the connecting element and adapted to cooperate with the adjustment extensions 11 a , 11 b . The cooperation between the locking arrangements 13 and the extensions 11 a , 11 b can be obtained by any system, such as a rack system as seen in the embodiment shown, for example, or by equivalent systems, such as wedging or the like. It is noted that the main band portion 8 forms at least half of the circumference of the headband 5 .
According to the preferred embodiment of the helmet 1 of the invention, the gripping members 7 a , 7 b are borne by or arranged on the adjustment extensions 11 a , 11 b so as to extend below the headband 5 . The adjustment extensions 11 a , 11 b bear, on their outer surface, a set of notches 14 (see e.g., FIG. 10 a ) adapted to cooperate with the locking member 13 a of a buckle 13 that forms the locking arrangement. These extensions 11 a , 11 b have arranged, at one of their ends, the gripping member 7 a , 7 b and, at the other end, is arranged an attaching or assembly arrangement, such as a slot 15 , in order to be each assembled to one end of the main band 8 so as to form the extension thereof.
It is noted, as shown in FIGS. 10 a and 10 b , that each adjustment extension 11 a , 11 b comprises a first longitudinal wall portion 16 a adapted to extend the main band, and a second longitudinal wall portion 16 b affixed to the first portion 16 a , and which bears the set of notches 14 . These two wall portions are arranged off-centered, one with respect to the other, in order to be placed in two distinct and parallel planes P 1 , P 2 . In this way, the second wall portion 16 b is located below the first 16 a . This second wall portion 16 b bears or includes, at its free end, the gripping member 7 a , 7 b that is formed at least partially of a transverse wall portion that is orthogonal to it. This member thus has a support surface 17 that is sufficient for allowing the user to bias it. This surface 17 extends transversely below the second wall portion 16 b of the adjustment extension 11 a , 11 b.
It is noted that the assembly of the extensions 11 a , 11 b on the main band portion 8 , due to attaching arrangement 15 , can occur in a plurality of positions. As seen in FIG. 4, the slot 15 of the extensions is capable of cooperating with a plurality of positioning pins 18 of the band 8 . Thus, this plurality of possible assemblies multiplies the possibilities for adjusting the size of the headband 5 by being advantageously combined with the adjusting device 6 of the invention. It is understood that one would not leave the scope of the invention by making the band and its adjustment extensions in one single piece.
According to the preferred embodiment of the helmet 1 of the invention, the locking buckles 13 adapted to cooperate with the extensions 11 a , 11 b are borne by or coupled to a rear connecting element 12 that partially forms the headband 5 . The headband 5 is arranged in the helmet so that the connecting element 12 is arranged centrally at the rear of the helmet 1 , substantially at the level of the user's nape.
This connecting element advantageously has two guiding slots 19 adapted to cooperate with a guiding pin 20 for each of the adjustment extensions 11 a , 11 b shown in FIG. 10 b . It bears, at its lateral ends, two buckles 13 shown in FIGS. 8 a - 8 d , each forming a passage 21 for the adjustment extensions 11 a , 11 b , and each bearing a locking member 13 a , such as a central lever provided with a locking projection 22 adapted to cooperate with the notches 14 in order to allow the sliding of the extension 11 a , 11 b in the passage 21 , solely in a direction corresponding to the tightening of the headband, and to prevent any sliding in the opposite direction. As known, the locking buckles 13 have an unlocking member 23 adapted to bias the lever 13 a and its projection 22 so that the latter is no longer engaged with the notches 14 , and so that the adjustment extensions 11 a , 11 b can slide in the opposite direction and thus allow loosening the headband 5 .
According to the preferred embodiment of the adjusting device 6 , the unlocking member 23 is a lever pivotally mounted on the body of the buckle 13 and adapted to cooperate with the locking lever 13 a by way of complementary ramps, as known.
According to the invention, the headband 5 has elastic biasing system 25 adapted to bias it towards its loosened position A shown in FIGS. 5 a and 6 a , i.e., a position where the gripping members 7 a and 7 b abut against the buckles 13 of the connecting element. Thus, when the user actuates the loosening levers 23 of the buckles 13 , the elastic biasing system or members 25 bias the adjustment extensions 11 a and 11 b to slide in their passage 21 toward their loosened position A.
According to the preferred embodiment, the elastic biasing system or members 25 are constituted of two return arms 25 formed by extensions of the rear connecting element 12 and which connect element 12 to the adjustment extensions 11 a , 11 b . Thus, when the user tightens the headband 5 , the return arms fold as seen in FIGS. 6 a - 6 c , thus biasing the adjustment extensions 11 a , 11 b against the locking arrangements 13 and 22 .
As shown in FIG. 7, it is noted that the guiding devices 20 are located at the end of the adjustment extensions, at the level of the gripping members 7 a , 7 b in order to slide in the slots 19 of the connecting element 12 located between the two locking buckles 13 . Furthermore, when the headband 5 is in the loosened position A, the gripping members 7 a , 7 b are separated by a distance “d” which is less than 15 centimeters and advantageously equal to approximately 8 centimeters so as to facilitate their actuating by the user. It is also noted that the cooperation between the connecting element 12 and its buckles 13 and the adjustment extensions 11 a , 11 b occurs in a plane P 2 located below that in which the main portion of the band 8 and the return arms 25 are located (i.e., P 1 ), whereas the gripping members 7 a , 7 b extend downwardly below plane P 2 .
According to the preferred embodiment, the constitutive members of the headband 5 , namely the main band portion 8 , the adjustment extensions 11 a , 11 b , the arrangements for locking and unlocking 13 , 22 and 23 , the connecting element 12 and its return arms 25 , are made of plastic and can be made by any method, such as by injection, for example. Nevertheless, the main portion of the band 8 and the connecting element 12 can comprise, on their inner surface, a padding adapted to provide comfort for the user. This padding can advantageously be glued or sewn on the band 8 , or it can be removably arranged, for example, by way of a quick fastener of the Velcro type (Registered Trademark).
It is noted that the helmet 1 of the invention has a vertical plane P of general symmetry, and that it has arrangements allowing the adjustment extensions 11 a , 11 b to be displaced symmetrically with respect to this plane P. In the previously described embodiment, these arrangements include the elastic arms 25 such that, when the user unlocks the band due to his acting on the unlocking members 23 , the elastic arms 25 act simultaneously and jointly to symmetrically drive back each of the adjustment extensions 11 a , 11 b . FIGS. 12 a , 12 b show an alternative according to which the displacement of one of the adjustment extensions 11 a or 11 b causes the displacement of the other adjustment extension 11 a or 11 b . According to this alternative, the two adjustment extensions 11 a , 11 b are connected mechanically and kinematically by a central transmission sprocket 30 , rotatably mounted on the connecting element 12 in the general plane P. It is noted that sprocket 30 cooperates through diametrical meshing with two additional extensions 31 a , 31 b of the main band, extending the adjustment extensions 11 a , 11 b.
According to the alternative embodiment shown in FIG. 12 a , the device also includes the elastic arrangements 25 of the first embodiment.
According to the alternative of FIG. 12 b , the elastic arrangements are constituted of an elastic system, not shown, such as a spring that acts on the transmission sprocket 30 .
Naturally, the invention is not limited to the embodiments described and shown by way of example, but it also encompasses all technical equivalents, as well as their combinations. | Protective helmet that includes a shell adapted to protect a user's head, an inner lining, and a headband having an adjusting device. The adjusting device includes two gripping members adapted to be manually moved towards or away from one another by the user in order to vary a size of the headband. This abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way. | 0 |
This application is a continuation-in-part of U.S. patent application Ser. No. 07/533,149, filed on Jun. 24, 1991, now abandoned.
FIELD OF THE INVENTION
This invention is directed to a method for the recovery of viscous hydrocarbonaceous fluids from a formation. More specifically, it is directed to the removal of said fluids from a formation containing heavy viscous hydrocarbons or tar sands by concentric horizontal wellbores in combination with solvent stimulation.
BACKGROUND OF THE INVENTION
Use of horizontal wells in oil reservoirs is currently of high interest within the oil industry. Horizontal wells allow more reservoir surface area to be contacted and thereby reduce inflow pressure gradients for reasonable oil production rates. Alternatively, for typical pressure gradients within the wellbore region, the productivity of a horizontal well is greater than that in a vertical well.
Possible benefits of horizontal wells are currently being exploited in the Canadian tar sands. Reservoirs in Canada that may be categorized as immobile under reservoir conditions include the Cold Lake and Athabasca deposits. Current practices for producing the above immobile tar sands include mining and solvent stimulation. Solvent stimulation is also used to remove very viscous oils from formations or reservoirs.
U.S. Pat. No. 4,373,585 issued to Fitch et al. discloses a method of recovering viscous oil from a viscous oil-containing formation wherein a selected solvent is injected into a fluid communication path in the lower portion of the formation intermediate between an injection well and a production well. A hydrocarbon solvent having a density less than oil contained in the formation and a viscosity not greater than 1/100 the viscosity of the oil contained in the formation under formation conditions is injected into the communication path. Fluids including oil are recovered from the production well until recovered fluid contains an unfavorable ratio of oil to solvent. The production well is shut-in and an additional quantity of the hydrocarbon solvent is injected into the fluid communication path.
Subsequently, the production well is also shut-in to permit the formation to undergo a soak period for a variable time. A driving fluid is then injected into the formation via the injection well and the oil is produced until there is an unfavorable ratio of oil to driving fluid. During the fluid drive recovery phase, the injection well and production well may be completed to be in fluid communication with the entire portion of the formation to obtain a more uniform displacement of the solvent and oil mixture in the formation by the driving fluid.
U.S. Pat. No. 4,293,035 issued to Fitch discloses a method of recovering viscous oil from a viscous oil bearing subsurface formation wherein a solvent is injected into a high mobility channel formed in the bottom of the formation intermediate an injection well and a production well. The solvent is injected until the ratio of produced oil to solvent becomes unfavorable. Thereafter, the injection of solvent is terminated and gas is injected into the high mobility channel to produce solvent and oil from the formation.
In U.S. Pat. No. 3,838,738 there is described a method for recovering viscous petroleum from petroleum-containing formations by first establishing a fluid communication path low in the formation. A heated fluid is then injected into the fluid communication path followed by injecting a volatile solvent such as carbon disulfide, benzene or toluene into the preheated flow path and continuing injecting the heated fluid and recovering fluids including petroleum from the production well.
In U.S. Pat. No. 3,500,917 there is disclosed a method for recovering crude oil from an oil-bearing formation having a water-saturated zone underlying the oil-saturated zone. A mixture of an aqueous fluid which has a density greater than the density of the crude oil and a solvent having a density less than the density of the crude oil are injected into the water-saturated zone and oil is produced from the formation.
U.S. Pat. No. 4,026,358 discloses a method for recovering heavy oil from a subterranean hydrocarbon-bearing formation traversed by at least one injection well and one production well wherein a slug of hydrocarbon solvent in amounts of 0.1 to about 20 percent of the formation pore volume and having a gas dissolved therein is injected into the formation via the injection well. Thereafter, a thermal sink is created in the formation by in-situ combustion or by injecting steam. The wells are then shut-in for a predetermined time to permit the formation to undergo a soak period, after which production is continued. Optionally, after the production period, the formation may be water flooded to recover additional oil from the formation.
Butler et al. in U.S. Patent No. 4,116,275 issued Sep. 26, 1978, teach a cyclic steam stimulation method for removing viscous fluids from a formation penetrated by a horizontal wellbore. Said wellbore contains a perforated casing and dual concentric tubing strings.
Solvents have a beneficial result since they dilute the crude, thereby making it mobile due to the reduction in viscosity. However, their use has not been practical commercially since this process evolves long periods of soak-time to allow the solvent to mix with the crude. Therefore, the critical factor is the soak time needed, and depending on the thickness of the oil zone, the soak time may vary from a year or two up to possibly eight or more years.
Therefore, what is needed is a solvent stimulation method for removing hydrocarbonaceous fluids from immobile tar sands or viscous fluids via a horizontal wellbore which will avoid long soak-times while providing for simultaneous solvent stimulation and continuous hydrocarbonaceous fluid production.
SUMMARY OF THE INVENTION
This invention is directed to a continuous single-well method for solvent stimulation in a horizontal wellbore containing concentric tubing strings therein which penetrate a reservoir. In the practice of this invention, a viscosity reducing agent is circulated into an inner tubing string of said wellbore so as to allow said agent to diffuse into a hydrocarbonaceous fluid producing zone of said reservoir. The viscosity reducing agent flows from the inner tubing string into the outer concentric tubing string and then diffuses out through perforations in said outer tubing string. Thereafter, it diffuses into the reservoir. Said agent is allowed to diffuse into the producing zone while the wellbore pressure is maintained at a pressure less than the reservoir pressure. Hence, a pressure difference exists thereby permitting oil flow from the reservoir to the wellbore. This difference in pressure causes hydrocarbonaceous fluid of reduced viscosity to continuously flow from the producing zone into the outer concentric tubing where it is produced to the surface.
Simultaneously, the viscosity reducing agent continues to diffuse into the productive zone of said reservoir. In this manner, a condition is created in the formation which causes the pressure gradient and a concentration gradient to be opposed so as to obtain simultaneous stimulation and continuous hydrocarbonaceous fluid production from the producing zone. Hydrocarbonaceous fluids mixed with the viscosity reducing agent are produced to the surface because of the pressure differential between the wellbore pressure and the reservoir pressure. Upon reaching the surface, hydrocarbonaceous fluids are separated from said reducing agent. Later, the solvent is recycled into the reservoir where it is used to remove additional hydrocarbonaceous fluids.
It is therefore an object of this invention to provide for the use of costlier solvents because of the invention's ability to reclaim and recycle solvents from produced hydrocarbonaceous fluids.
It is another object of this invention to provide for a solvent stimulation method which requires the drilling of only one well.
It is another further object of this invention to allow for the continuous production of oil at a higher rate than is presently obtained with solvent stimulation methods currently being used.
It is yet another object of this invention to provide for more efficient draining of a formation or reservoir when utilizing a horizontal wellbore.
It is an even yet further object of this invention to stimulate a large volume of oil through an extensive area penetrated by a horizontal wellbore via a diffusive flux.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a reservoir penetrated by a horizontal wellbore with a radially solvent stimulated area therearound.
FIG. 2 is a sectional view of a horizontal wellbore as described herein which depicts the well configuration and spatial profiles.
FIG. 3 is a graphical representation which depicts enhanced oil productivity through continuous solvent stimulation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the drawing illustrates a subterranean formation or reservoir 10 which contains heavy viscous hydrocarbonaceous fluids. These fluids are disposed below the earth's surface 8 and beneath overburden 30. A wellbore having a substantially vertical section 12 and a substantially horizontal section 14 is drilled to penetrate formation 10 and extend therethrough. A continuous casing element 16 which is shown in greater detail in FIG. 2, commonly called a liner, having perforations or slots 18 is shown extending through the entire length of the wellbore. Concentric inner tubing string 20 is disposed inside of casing 16. The inner tubing 20 is placed centrally within the surrounding larger diameter formed by casing 16. Inner tubing 20 cooperates with casing 16 to form an annular space 24. Inner concentric tubing string 20 distal end terminates flush with distal end of casing 16 Concentric inner tubing string 20 and annulus 24 formed by inner tubing 20 in conjunction with casing 16 passes through wellhead 28 and communicates with the usual production conduits. As is shown in FIG. 1, a separator unit 32 is in communication with annular space 24 formed by casing 16 and inner tubing 20.
The horizontal well is drilled to penetrate the subterranean reservoir formation 10 and to extend substantially horizontally a suitable distance through the formation so as to remove hydrocarbonaceous fluids therefrom. Techniques for drilling horizontally deviated wellbores are well known and, therefore, will not be discussed further herein. After drilling the horizontal wellbore, the drill bit is removed and a perforated outer casing 16 is positioned inside the drillstring. The drillstring is then removed and concentric tubing string 20 is run into the casing or liner 16. As is known to those skilled in the art, concentric inner tubing 20 and slotted liner 16 may be run into the wellbore in any convenient manner. Inner concentric tubing string 20 and annulus 24 formed by casing 16 with perforations 18 therein are in fluid communication with the formation.
U.S. Patent No. 4,116,275 issued to Butler et al. discloses a method for recovering hydrocarbons from a hydrocarbon-bearing formation via a horizontal well. A well is drilled to penetrate a formation and extend substantially horizontally into the formation for a suitable distance. Dual concentric drill tubing strings were used in conjunction with steam to remove hydrocarbons from the formation. This patent is hereby incorporated by reference herein in its entirety.
In the practice of this invention, a viscosity reducing agent or solvent is injected into formation 10 via inner tubing string 20. Once it reaches the end of tubing string 20, said viscosity reducing agent or solvent enters into an annulus 24 formed by continuous casing element 16 and inner tubing string 20. This viscosity reducing agent or solvent enters into annulus 24 and circulates around inner concentric tubing string 20. The pressure gradient in the tubing is sufficient to cause said reducing agent or solvent to circulate around inner concentric tubing string 20 but is insufficient to cause it to flow convectively into reservoir 10. Said solvent continues to circulate around inner concentric tubing string 20 until it has progressed along the entire length of horizontal wellbore 14. Once in the annulus along the entire length of horizontal well 14, said reducing agent or solvent diffuses into formation 10 through said perforations. It continues to diffuse into said formation 10 and proceeds radially and outwardly from the slotted outer liner 16 Thus, the solvent forms a radially stimulated zone 26 around outer liner 16. Because the concentration of said viscosity reducing agent or solvent is greater in annulus 24 than in the formation 10, said reducing agent continually diffuses into formation 10 so as to reduce the viscosity of a heavy viscous hydrocarbonaceous fluid or tar sands in formation 10.
As the viscosity reducing agent continues to diffuse into the formation from radially stimulated zone 26, oil of reduced viscosity flows into slotted outer liner 16. Of course, the viscosity of the oil further away from slotter liner is greater than that oil in radially stimulated zone 26. This is so because the solvent concentration is greater in radially stimulated zone 26. For this reason, oil of reduced viscosity flows into slotted lever 16. Reservoir or formation fluids are thus saturated with solvent at the wellbore and are undersaturated to some degree into the formation. After some initial transient period, a steady state is reached where a rate of solvent diffusion is exactly counterbalanced by convective transport of solubilized material or oil of reduced viscosity into the wellbore to the surface.
Circulation pressure of solvent into the wellbore is maintained so as to allow continuous diffusion of solvent into stimulated zone 26 while allowing the formation pressure to remain at a pressure sufficient to force oil to the surface. Because of this circulation pressure maintenance, oil of decreased viscosity containing solvent is removed to the surface. A dynamic condition exists in the wellbore and formation which causes solvent to continuously diffuse from an area of higher concentration to one of lower concentration in the formation. The rate of solvent diffusion into the formation is greater than the volume of solvent removed from the formation with the oil of reduced viscosity. Although oil of reduced viscosity containing solvent is continuously removed from the formation, solvent is continuously diffusing into the formation which creates a continuous dynamic state of solvent diffusion into the formation and continuous removal of reduced viscosity oil from the formation.
Oil of reduced viscosity flows to the surface because of existing pressure in the formation in conjunction with the oil having become reduced in viscosity thereby imparting mobility to the oil. In the absence of a reduction in the viscosity of the viscous oil so as to impart mobility thereto, existing pressure in the formation would not cause it to flow to surface because its viscosity would be too great.
A "heavy" crude oil or viscous hydrocarbonaceous fluid is defined to be one that is viscous and has poor flow characteristics in the reservoir. Generally, it is a crude oil that has an API gravity of about 20° or lower. Where the formation contains oils of a high initial mobility, the stimulated zone may not be large enough to give incremental benefits since convective and diffusional fluxes are counter-current.
As defined herein, diffusion is the spontaneous mixing of one substance with another when in contact with or when separated by a microporous barrier. Said mixing takes place at the molecular level. The rate of diffusion is proportional to the concentration gradient of substances involved and increases with temperature. Diffusion herein takes place counter to the gravity, and the rate at which the different molecules diffuse in inversely proportional to the square roots of the densities.
While the reducing agent or solvent is diffusing from outer liner 16, hydrocarbonaceous fluids which have intermixed diffusionally with said solvent obtain a reduced viscosity. This reduced viscosity causes the hydrocarbonaceous fluids, water and solvent intermixed therewith which have accumulated in stimulated zone 26 to flow into outer liner 16 via perforations 18 contained therein. This flow is caused because pressure within formation 10 is greater than the pressure which is in the horizontal wellbore 14. Thus, there is a continuous migration of oil of reduced viscosity from the stimulated zone 26 into the casing liner 16 while solvent continues to diffuse into formation 10. Formation pressure causes oil of reduced viscosity, water and solvent intermixed therewith to flow into the liner 16 and continue up vertical section of wellbore 12 where it is produced to the surface via wellhead 28. Once the mixture has reached the surface, it is directed into a separator unit 32. Once in the separator unit 32, hydrocarbonaceous fluids are separated from water and solvent. Reclaimed solvent is subsequently recycled back into the formation by inner concentric tubing string 20. Hydrocarbonaceous fluids are removed via perforated liner 16 and sent to storage. Solvent gases which can be used herein include carbon dioxide, C 1 -C 4 hydrocarbons, carbon monoxide, flu gases, helium, hydrogen, and almost any gas which would be soluble in oil.
Liquid solvents which can be used herein include methanol, ethanol, C 5 -C 10 hydrocarbons, toluene, or carbon disulfide and mixtures thereof. When gases are used herein an additional advantage is obtained because it serves as a gas lift and eases the separation of produced fluids at the surface.
This diffusional solvent/solute stimulation process works because it stimulates a large volume of oil through the extensive surface area of the perforated horizontal wellbore. This extensive stimulation area causes a mass transfer process to be viable. In addition to the mass transfer process which is performed with the solvents, solvent usage can be combined with thermal stimulation to obtain even greater benefits. The solvent stimulation process alone or in combination with thermal stimulation can be used in heavy, medium or light oils. Thermal heating can be obtained from electrical induction or electromagnetic heating processes which are known to those skilled in the art. A representative process is mentioned in U.S. Pat. No. 4,485,869 which issued to Sresty et al. and which is incorporated herein by reference. Another representative process is found in U.S. Pat. No. 3,547,193 which issued to Gill. This patent is hereby incorporated by reference.
As taught in Gill, an electrode is placed in the formation which extends into the formation from a borehole which is proximate to the area containing the horizontal well to allow heating by an electrical current. Thereafter, electrical current is caused to flow from the electrode through the formation to heat the area containing the horizontal wellbore. The electrode comprises conductive shot or pellets that extend into the formation and is electrically connected to a source of supply voltage.
The pseudo steady state solution for simultaneous solvent stimulation and production which relates the pressure drawdown and the associated fluid recovery is the result of a combination mass balance, mole balance, empirical viscosity correlation, and Darcy's law. The governing differential equations for this process are depicted in FIG. 3 where the graph shows enhanced oil productivity through continuous solvent stimulation.
In FIG. 3, r e /r w is the ratio of the drainage radius to the wellbore radius. As shown, q is the unstimulated oil rate, L is the length of the wellbore, D is the diffusion coefficient within the reservoir, and q* is the stimulated oil rate.
Referring to FIG. 3, the following example is an illustration of how this disclosed process can be utilized. Initially, assume that a 1,000 ft. horizontal wellbore is producing at an unstimulated primary production rate of 10 bbl/day. Using laboratory data, it has been determined that the diffusivity of our solvent (CO 2 ) in the crude oil was 4.0×10- 6 bbl/ft day. For this case the ratio of the stimulated to unstimulated oil viscosity is 1,000 and r e /r w is 100. From this information the absissca of FIG. (3) is computed to be 400. Reading upwards and over to the ordinate of the figure, a stimulated oil rate ratio of 1.5 to 2.0 is shown. Thus, circulation of CO2 within the wellbore using diffusion as the stimulating process results in an increase in the oil rate of 50 to 100%.
In another preferred embodiment, the horizontal well can be used in conjunction with an interwell which is at a distance remote from the horizontal wellbore but which is in fluid communication with said wellbore. In this embodiment, the interwell is pressurized either by steam stimulation or by the use of some other fluid so as to increase the formation pressure thereby obtaining a more rapid production of hydrocarbonaceous fluids from the reservoir. An interwell or intermediate well in conjunction with a solvent flooding method is disclosed by Anderson in U.S. Pat. No. 4,398,602 which issued on Aug. 16, 1983. This patent is hereby incorporated by reference herein.
Obviously, many other variations and modifications of this invention as previously set forth may be made without departing from the spirit and scope of this invention as those skilled in the art readily understand. Such variations and modifications are considered part of this invention and within the purview and scope of the appended claims. | A solvent stimulation process whereby a viscosity reducing agent is circulated through a horizontal well via a production string. Said agent exits the production string and enters an annulus formed by said string and a liner. Said agent diffuses into the reservoir at a pressure below the reservoir pressure. As said agent diffuses through the reservoir under the influence of a concentration gradient, it reduces the oil's viscosity and makes it mobile. Simultaneously, oil of reduced viscosity migrates into the well under a pressure drawdown influence. A pseudo steady state production rate is achieved when convective movement of the oil of reduced viscosity is exactly counterbalanced by the diffusional rate of the viscosity reducing agent in a stimulated radial zone along said well. This stimulates a large volume of oil through the extensive surface area of the wellbore thus producing increased volumes of hydrocarbonaceous fluids from the reservoir. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] N/A
BACKGROUND OF THE INVENTION
[0002] The present invention is related to the field of computer graphics, and in particular to volume graphics.
[0003] Volume graphics is the subfield of computer graphics that deals with the visualization of objects or phenomena represented as sampled data in three or more dimensions. These samples are called volume elements, or “voxels,” and contain digital information representing physical characteristics of the objects or phenomena being studied. For example, voxel values for a particular object or system may represent density, type of material, temperature, velocity, or some other property at discrete points in space throughout the interior and in the vicinity of that object or system.
[0004] Volume rendering is the part of volume graphics concerned with the projection of volume data as two-dimensional images for purposes of printing, display on computer terminals, and other forms of visualization. By assigning colors and transparency to particular voxel data values, different views of the exterior and interior of an object or system can be displayed. For example, a surgeon needing to examine the ligaments, tendons, and bones of a human knee in preparation for surgery can utilize a tomographic scan of the knee and cause voxel data values corresponding to blood, skin, and muscle to appear to be completely transparent. The resulting image then reveals the condition of the ligaments, tendons, bones, etc. which are hidden from view prior to surgery, thereby allowing for better surgical planning, shorter surgical operations, less surgical exploration and faster recoveries. In another example, a mechanic using a tomographic scan of a turbine blade or welded joint in a jet engine can cause voxel data values representing solid metal to appear to be transparent while causing those representing air to be opaque. This allows the viewing of internal flaws in the metal that would otherwise be hidden from the human eye.
[0005] Real-time volume rendering is the projection and display of volume data as a series of images in rapid succession, typically at 30 frames per second or faster. This makes it possible to create the appearance of moving pictures of the object, phenomenon, or system of interest. It also enables a human operator to interactively control the parameters of the projection and to manipulate the image, while providing to the user immediate visual feedback. It will be appreciated that projecting tens of millions or hundreds of millions of voxel values to an image requires enormous amounts of computing power. Doing so in real time requires substantially more computational power.
[0006] Further background on volume rendering is included in a Doctoral Dissertation entitled “Architectures for Real-Time Volume Rendering” submitted by Hanspeter Pfister to the Department of Computer Science at the State University of New York at Stony Brook in December 1996, and in U.S. Pat. No. 5,594,842, “Apparatus and Method for Real-time Volume Visualization.” Additional background on volume rendering is presented in a book entitled “Introduction to Volume Rendering” by Barthold Lichtenbelt, Randy Crane, and Shaz Naqvi, published in 1998 by Prentice Hall PTR of Upper Saddle River, N.J.
[0007] The reconstruction of images from sampled data is the domain of a branch of mathematics known as “sampling theory”. From the well-known Nyquist sampling theorem, the frequency at which data must be sampled must equal or exceed twice the spatial frequency of the data in order to obtain faithful reconstruction of the information in the data. This constraint is true in multiple dimensions as well as in one dimension.
[0008] Volume data sets are typically organized as samples along regular grids in three dimensions, which defines the spatial frequency inherent in the data. In order to project three-dimensional volume data onto a two-dimensional image plane by ray-casting, the data must be re-sampled at a sampling frequency equal to or greater than the Nyquist frequency. If the sampling frequency is not sufficiently high, undesirable visual artifacts caused by aliasing appear in the rendered image, especially moving images such as images being manipulated by a human viewer in real-time. Thus one of the challenges in real-time volume rendering is the efficient re-sampling of volume data in support of high-quality rendering from an arbitrary and changing view direction.
[0009] Another aspect of volume rendering is the application of artificial “illumination” or “lighting” to the rendered image, which is the creation of highlights and shadows that are essential to a realistic two-dimensional representation of a three-dimensional object. Lighting techniques are well-known in the computer graphics art and are described, for example, in the textbook “Computer Graphics: Principles and Practice,” 2nd edition, by J. Foley, A. vanDam, S. Feiner, and J. Hughes, published by Addison-Wesley of Reading, Mass., in 1990.
[0010] One illumination technique that generates very high quality images is known as “Phong illumination” or “Phong shading”. The Phong illumination algorithm requires knowledge of the orientation of surfaces appearing in the rendered image. Surface orientation is indicated by a vector referred to as a “normal”. In volume rendering, one way to obtain the normal is to estimate gradients for the samples of the volume data. Various techniques can be used to calculate gradients. According to one commonly-used technique, the gradients are estimated by calculating “central differences”. That is, the gradient in a given direction at a sample point is equal to the difference between the values of the two sample points surrounding the sample in the indicated direction.
[0011] The performance of illumination algorithms in general is very sensitive to the accuracy of the gradient calculation. To obtain the best-quality rendered image, it is important that gradients be calculated very accurately.
[0012] In a ray-casting system in which sample planes are normal to the rays, it is fairly straightforward to calculate gradients from samples of the volume data using central differences. There are, however, systems in which sample planes are parallel to the planes of voxels, so that the angle between sample planes and rays is dependent on view angle. One example of such a system is shown in the aforementioned Doctoral Dissertation. In these systems, the calculation of gradients is substantially more difficult, because the weight to be given neighboring samples is dependent on the viewing angle.
[0013] One prior technique for calculating gradient values has been to calculate an intermediate value using unity weights, and then to apply a correction factor that is a function of viewing angle. Unfortunately, this technique is both complicated and inaccurate. It would be desirable to improve the performance of illumination algorithms such as Phong illumination by enabling the calculation of accurate gradients in a manner that lends itself to efficient hardware implementation in a volume rendering processor.
BRIEF SUMMARY OF THE INVENTION
[0014] In accordance with the present invention, a ray-casting volume rendering processor is disclosed which in which volume data is efficiently re-sampled as an image is rendering from an arbitrary and changing view direction. Accurate gradients are calculated for use in a Phong illumination algorithm, and high rendering throughput is maintained while the appearance of sampling-induced artifacts in the rendered image is minimized.
[0015] The disclosed volume rendering processor includes voxel memory interface logic operative to continually retrieve the voxels from a voxel memory in which a volume data set is stored. The voxel memory is scanned in order with respect to a Cartesian coordinate system having mutually perpendicular X, Y and Z coordinate axes, the Z axis being the axis more nearly parallel to a predefined viewing direction than either the X or Y axes. Interpolation logic coupled to the voxel memory interface logic continually receives the retrieved voxels and calculates samples such that (i) each sample lies along a corresponding imaginary ray extending through the object parallel to the viewing direction, (ii) each sample is the result of interpolation among a surrounding set of voxels in the Cartesian coordinate system, and (iii) the spatial frequency of the samples in one or more or the X, Y and Z directions is greater than the spatial frequency of the voxels in the same direction. This “supersampling” greatly reduces the presence of visual artifacts in the rendered image.
[0016] In another disclosed technique, X and Y components of gradients are calculated from samples emitted by the interpolation logic, and Z gradients are calculated by (i) calculating Z gradients at the voxel positions from voxel values retrieved from memory, and (ii) interpolating the voxel Z gradients to arrive at the Z gradients at the sample positions. The calculation of Z-gradients from the voxels rather than from samples greatly simplifies the calculation of the Z gradients while attaining greater accuracy over prior approaches.
[0017] In yet another disclosed technique, the interpolation logic generates (i) a first set of intermediate interpolation values by interpolating between adjacent voxels in a first dimension, and (ii) a second set of intermediate interpolation values resulting by interpolating between the first intermediate interpolation values in a second dimension, and the samples representing the re-sampling of the retrieved voxels are calculated by interpolating between the second intermediate interpolation values in the third dimension. The intermediate interpolation values are used to calculate multiple adjacent samples, so that high throughput in the interpolation stages is maintained.
[0018] Other aspects, features, and advantages of the present invention are disclosed in the detailed description which follows.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0019] The foregoing features of this invention, as well as the invention itself, may be more fully understood from the following Detailed Description of the Invention, and Drawing, of which:
[0020] [0020]FIG. 1 is a diagrammatic illustration of a volume data set;
[0021] [0021]FIG. 2 is a diagrammatic illustration of a view of a volume data set being projected onto an image plane by means of ray-casting;
[0022] [0022]FIG. 3 is a cross-sectional view of the volume data set of FIG. 2;
[0023] [0023]FIG. 4 is a diagrammatic illustration of the processing of an individual ray by ray-casting;
[0024] [0024]FIG. 5 is a block diagram of a pipelined processing element for real-time volume rendering in accordance with the present invention;
[0025] [0025]FIG. 6 is a schematic representation of an organization of voxels useful for volume rendering according to the present invention;
[0026] [0026]FIG. 7 is a diagram showing the relationship between voxels and samples in the processing element of FIG. 5;
[0027] [0027]FIG. 8 is a diagram illustrating how gradients are calculated from sample points in the processing element of FIG. 5;
[0028] [0028]FIG. 9 is a block diagram of the portion of the processing element of FIG. 5 that calculates samples and gradients for use by subsequent processing stages;
[0029] [0029]FIGS. 10 and 11 are timing diagrams illustrating the operation of slice buffers in the processing element of FIG. 9; and
[0030] [0030]FIG. 12 is a block diagram of weight generator logic in the processing element of FIG. 9.
DETAILED DESCRIPTION OF THE INVENTION
[0031] Referring now to FIG. 1 and by way of further background, a view of a three-dimensional volume data set 10 is shown. FIG. 1 depicts an array of voxel positions 12 arranged in the form of a rectangular solid. More particularly, the voxel positions fill the solid in three dimensions and are uniformly spaced. The position of each voxel can be represented in a coordinate system defined by the three axes 11 labeled X, Y, and Z. Associated with each voxel position is one or more data values representing some characteristics of the object, system, or phenomenon under study, for example density, type of material, temperature, velocity, opacity or other properties at discrete points in space throughout the interior and in the vicinity of that object or system. It is convenient to represent a volume data set in a computer as a three-dimensional array of values, with the value at array index position (X, Y, Z) corresponding to the volume data values at coordinates (X, Y, Z) in three-dimensional space.
[0032] [0032]FIG. 2 illustrates an example of a volume data set 10 comprising an array of slices from a tomographic scan of the human head. A two-dimensional image plane 16 represents the surface on which a volume rendered projection of the human head is to be displayed. In a technique known as ray-casting, rays 18 are cast from pixel positions 22 on the image plane 16 through the volume data set 10 , with each ray accumulating color and opacity from the data at voxel positions as it passes through the volume. In this manner the color, transparency, and intensity as well as other parameters of a pixel are extracted from the volume data set as the accumulation of data at sample points 20 along the ray. In this example, voxel values associated with bony tissue are assigned an opaque color, and voxel values associated with all other tissue in the head are assigned a transparent color. Therefore, the result of accumulation of data along a ray and the attribution of this data to the corresponding pixel result in an image 19 in viewing plane 16 that appears to an observer to be an image of a three-dimensional skull, even though the actual skull is hidden from view by the skin and other tissue of the head.
[0033] In order to appreciate more fully the method of ray-casting, FIG. 3 depicts a two-dimensional cross-section of a three-dimensional volume data set 10 of FIG. 2. The first and second dimensions correspond to the dimensions illustrated on the plane of the page. The third dimension of volume data set 10 is perpendicular to the printed page so that only a cross section of the data set can be seen in the figure. Voxel positions are illustrated by dots 12 in the figure. The voxels associated with each position are data values that represent some characteristic or characteristics of a three-dimensional object 14 at fixed points of a rectangular grid in three-dimensional space. Also illustrated in FIG. 3 is a one-dimensional view of a two-dimensional image plane 16 onto which an image of object 14 is to be projected in terms of providing pixels 22 with the appropriate characteristics. In this illustration, the second dimension of image plane 16 is also perpendicular to the printed page.
[0034] In the technique of ray-casting, rays 18 are extended from pixels 22 of the image plane 16 through the volume data set 10 . Each ray accumulates color, brightness, and transparency or opacity at sample points 20 along that ray. This accumulation of light determines the brightness and color of the corresponding pixels 22 . Thus while the ray is depicted going outwardly from a pixel through the volume, the accumulated data can be thought of as being transmitted back down the ray where it is provided to the corresponding pixel to give the pixel color, intensity and opacity or transparency, amongst other parameters.
[0035] It will be appreciated that although FIG. 3 suggests that the third dimension of volume data set 10 and the second dimension of image plane 16 are both perpendicular to the printed page and therefore parallel to each other, in general this is not the case. The image plane may have any orientation with respect to the volume data set, so that rays 18 may pass through the volume data set 10 at any angle in all three dimensions.
[0036] It will also be appreciated that sample points 20 do not necessarily intersect the voxel 12 coordinates exactly. Therefore, the value of each sample point must be synthesized from the values of voxels nearby. That is, the intensity of light, color, and transparency or opacity at each sample point 20 must be calculated or interpolated as a mathematical function of the values of nearby voxels 12 . The re-sampling of voxel data values to values at sample points is an application of the branch of mathematics known as sampling theory. The sample points 20 of each ray 18 are then accumulated by another mathematical function to produce the brightness and color of the pixel 22 corresponding to that ray. The resulting set of pixels 22 forms a visual image of the object 14 in the image plane 16 .
[0037] [0037]FIG. 4 illustrates the processing of an individual ray. Ray 18 passes through the three-dimensional volume data set 10 at some angle, passing near or possibly through voxel positions 12 , and accumulates data at sample points 20 along each ray. The value at each sample point is synthesized as illustrated at 21 by an interpolation unit 103 (see FIG. 5), and its gradient is calculated as illustrated at 23 by a gradient estimation unit 111 (see FIG. 5). The sample point values from sample point 20 and the gradient 25 for each sample point are then processed in the pipeline to assign color, brightness or intensity, and transparency or opacity to each sample. As illustrated at 27 , this is done via pipeline processing in which red, green and blue hues as well as intensity and opacity or transparency are calculated. Finally, the colors, levels of brightness, and transparencies assigned to all of the samples along all of the rays are applied as illustrated at 29 to a compositing unit 124 that mathematically combines the sample values into pixels depicting the resulting image 32 for display on image plane 16 .
[0038] The calculation of the color, brightness or intensity, and transparency of sample points 20 is done in two parts. In one part, a mathematical function such as trilinear interpolation is utilized to take the weighted average of the values of the eight voxels in a cubic arrangement immediately surrounding the sample point 20 . The resulting average is then used to assign a color and opacity or transparency to the sample point by some transfer function. In the other part, the mathematical gradient of the sample values at each sample point 20 is estimated by a method such as taking the differences between nearby sample points. It will be appreciated that these two calculations can be implemented in either order or in parallel with each other to produce mathematically equivalent results. The gradient is then used in a lighting calculation to determine the brightness of the sample point. Examples of well-known lighting can be found in the aforementioned textbook by Foley, vanDam, Feiner and Hughes entitled “Computer Graphics: Principles and Practice”.
[0039] [0039]FIG. 5 depicts a block diagram of a pipelined processor appropriate for performing the calculations illustrated in FIG. 4. The pipelined processor comprises a plurality of pipeline stages, each stage of which holds one data element, so that a plurality of data elements are being processed at one time. Each data element is at a different degree of progress in its processing, and all data elements move from stage to stage of the pipeline in lock step. At the first stage of the pipeline, a series of voxel data values flow into the pipeline at a rate of one voxel per cycle from the voxel memory 100 , which operates under the control of an address generator 102 . The interpolation unit 104 receives voxel values located at coordinates X, Y and Z in three-dimensional space, where X, Y and Z are each integers. The interpolation unit 104 is a set of pipelined stages that synthesize data values at sample points between voxels corresponding to positions along rays that are cast through the volume. During each cycle, one voxel enters the interpolation unit and one interpolated sample value emerges. The latency between the time a voxel value enters the pipeline and the time that an interpolated sample value emerges depends upon the number of pipeline stages and the internal delay in each stage.
[0040] The interpolation stages of the pipeline comprise a set of interpolator stages 104 and three FIFO elements 106 , 108 , 110 for recirculating data through the stages. In the current embodiment, these are all linear interpolations, but other interpolation functions such as cubic and LaGrangian may also be employed. In the illustrated embodiment, interpolation is performed in each dimension as a separate stage, and the respective FIFO elements are included to recirculate data for purposes of interpolating between voxels that are adjacent in space but widely separated in the time of entry to the pipeline. The delay of each FIFO is selected to be exactly the amount of time elapsed between the reading of one voxel and the reading of an adjacent voxel in that particular dimension so that the two can be combined in an interpolation function. It will be appreciated that voxels can be streamed through the interpolation stage at a rate of one voxel per cycle with each voxel being combined with the nearest neighbor that had been previously recirculated through the FIFO associated with that dimension.
[0041] Three successive interpolation stages, one for each dimension, are concatenated and voxels can pass through the three stages at a rate of one voxel per cycle at both input and output. The throughput of the interpolation stages is one voxel per cycle independent of the number of stages within the interpolation unit and independent of the latency of the data within the interpolation unit and the latency of the recirculation stages within that unit. Thus, the interpolation unit converts voxel values located at integer positions in XYZ space into sample values located at non-integer positions at the rate of one voxel per cycle. In particular, the interpolation unit converts values at voxel positions to values at sample positions disposed along the rays.
[0042] Following the interpolation unit 104 is a gradient estimation unit 112 , which also comprises a plurality of pipelined stages and recirculation FIFOs. The function of the gradient unit 112 is to derive the rate of change of the sample values in each of the three dimensions. The gradient estimation unit operates in a similar manner to the interpolation unit 104 and computes the rate of change of the sample values in each of the three dimensions. Note, the gradient is used to determine a normal vector for illumination, and its magnitude may be used as a measure of the existence of a surface when the gradient magnitude is high. In the present embodiment the calculation is obtained by taking central differences, but other functions known in the art may be employed. Because the gradient estimation unit is pipelined, it receives one interpolated sample per cycle, and it outputs one gradient per cycle. As with the interpolation unit, each gradient is delayed from its corresponding sample by a number of cycles which is equal to the amount of latency in the gradient estimation unit 112 including respective recirculation FIFOs 114 , 116 , 118 . The delay for each of the recirculation FIFOs is determined by the length of time needed between the reading of one interpolated sample and nearby interpolated samples necessary for deriving the gradient in that dimension.
[0043] The interpolated sample and its corresponding gradient are concurrently applied to the classification and illumination units 120 and 122 respectively at a rate of one interpolated sample and one gradient per cycle. Classification unit 120 serves to convert interpolated sample values into colors in the graphics system; i.e., red, green, blue and alpha values, also known as RGBA values. The red, green, and blue values are typically fractions between zero and one inclusive and represent the intensity of the color component assigned to the respective interpolated sample value. The alpha value is also typically a fraction between zero and one inclusive and represents the opacity assigned to the respective interpolated sample value.
[0044] The gradient is applied to the illumination unit 122 to modulate the newly assigned RGBA values by adding highlights and shadows to provide a more realistic image. Methods and functions for performing illumination are well known in the art. The illumination and classification units accept one interpolated sample value and one gradient per cycle and output one illuminated color and opacity value per cycle.
[0045] Although in the current embodiment, the interpolation unit 104 precedes the gradient estimation unit 112 , which in turn precedes the classification unit 120 , it will be appreciated that in other embodiments these three units may be arranged in a different order. In particular, for some applications of volume rendering it is preferable that the classification unit precede the interpolation unit. In this case, data values at voxel positions are converted to RGBA values at the same positions, then these RGBA values are interpolated to obtain RGBA values at sample points along rays.
[0046] The compositing unit 124 combines the illuminated color and opacity values of all sample points along a ray to form a final pixel value corresponding to that ray for display on the computer terminal or two-dimensional image surface. RGBA values enter the compositing unit 124 at a rate of one RGBA value per cycle and are accumulated with the RGBA values at previous sample points along the same ray. When the accumulation is complete, the final accumulated value is output as a pixel to the display or stored as image data. The compositing unit 124 receives one RGBA sample per cycle and accumulates these ray by ray according to a compositing function until the ends of rays are reached, at which point the one pixel per ray is output to form the final image. A number of different functions well known in the art can be employed in the compositing unit, depending upon the application.
[0047] Between the illumination unit 122 and the compositing unit 124 , various modulation units 126 may be provided to permit modification of the illuminated RGBA values, thereby modifying the image that is ultimately viewed. One such modulation unit is used for cropping the sample values to permit viewing of a restricted subset of the data. Another modulation unit provides a function to show a slice of the volume data at an arbitrary angle and thickness. A third modulation unit provides a three-dimensional cursor to allow the user or operator to identify positions in XYZ space within the data. Each of the above identified functions is implemented as a plurality of pipelined stages accepting one RGBA value as input per cycle and emitting as an output one modulated RGBA value per cycle. Other modulation functions may also be provided which may likewise be implemented within the pipelined architecture herein described. The addition of the pipelined modulation functions does not diminish the throughput (rate) of the processing pipeline in any way but rather affects the latency of the data as it passes through the pipeline.
[0048] In order to achieve a real-time volume rendering rate of, for example, 30 frames per second for a volume data set with 256×256×256 voxels, voxel data must enter the pipelines at 256 3 ×30 frames per second or approximately 500 million voxels per second. It will be appreciated that although the calculations associated with any particular voxel involve many stages and therefore have a specified latency, calculations associated with a plurality of different voxels can be in progress at once, each one being at a different degree of progression and occupying a different stage of the pipeline. This makes it possible to sustain a high processing rate despite the complexity of the calculations.
[0049] It will be further appreciated that the above described pipelined processor can be replicated as a plurality of parallel pipelines to achieve higher throughput rates by processing adjacent voxels in parallel. The cycle time of each pipeline is determined by the number of voxels in a typical volume data set, multiplied by the desired frame rate, and divided by the number of pipelines. In a preferred embodiment, the cycle time is 7.5 nanoseconds and four pipelines are employed in parallel.
[0050] [0050]FIG. 6 illustrates an organization of the voxels 12 that is used during the rendering of a volume dataset 10 according to the illustrated embodiment. The Z axis of the organization of FIG. 6 is pre-selected to be the axis of the volume data set that is more nearly parallel to the view direction than either of the other two axes. Moreover, the direction of increasing coordinates along the Z axis is pre-selected to be the direction of rays 18 passing from the image plane 16 toward the volume data set 10 . The X and Y axes of this organization are pre-selected following the selection of the Z axis, so that rays from the image plane 16 proceeding parallel to the view direction always point in the direction of non-decreasing coordinates along both the X and Y axes. It will be appreciated that as the view direction changes from frame to frame in a real-time volume rendering system, the selection of the X, Y and Z axes and their directions must change accordingly.
[0051] As shown in FIG. 6, for a given selection of the X, Y and Z axes, the data set 10 is divided into parallel “slices” 230 in the Z direction. Each slice 30 is divided into “beams” 232 in the Y direction, and each beam 232 consists of a row of voxels 12 in the X direction. The voxels 12 within a beam 232 are divided into groups 234 of voxels 12 which as described above are processed in parallel by the four rendering pipelines 212 . The groups 234 are then processed in left-to-right order within a beam 232 ; beams 232 are processed in top-to-bottom order within a slice 230 ; and slices 230 are processed in order front-to-back. This order of processing corresponds to a three-dimensional scan of the data set 10 in the X, Y, and Z directions.
[0052] [0052]FIG. 7 illustrates how samples 20 of the voxel data are calculated. A sample 20 is indicated as S x′, y′, z′ , where x′, y′ and z′ indicate position along the respective axes. The position of a sample S x′, y′, z′ with respect to a corresponding voxel V x, y, z is expressed in terms of three fractional weights w x , w y and w z . Each weight represents the position of a sample as a fraction of the distance between neighboring voxels along the corresponding axis. The sample value is calculated by a well-known process called tri-linear interpolation. One way of performing tri-linear interpolation is via the following three steps:
[0053] 1. Four intermediate samples U x, y, z′ , U (x+1), y, z′ , U x, (y+1), z′ and U (z+1), (y+1), z′ are calculated as follows:
U x, y, z′ =V x, y, z +W z ( V x, y, (x+1) −V x, y, z )
U (x+1), y, z′ =V (x+1), y, z +W z (V (x+l), y, (z+1) −V (x+1), y, z )
U x, (y+1), z′ =V x, (y+1), z +W z (V x, (y+1), (z+1) −V x, (y+1), z )
U (x+1), (y+1),z′ =V (x+1), (y+1),z′ +W z ( V (x+1), (y+1), (z+1) −V (x+1), (y+1), z )
[0054] 2. Two intermediate samples T x, y′, z′ and T (x+1), y′, z′ are calculated as follows:
T x, y, z′ =U x, y, z′ +W y (U x, (y+1), z′ −U x, y, z′ )
T (x+1), y, z′ =U (x+1), y, z′ +W y ( U (x+1), (y+1),z′ −U (x+1), y, z′ )
[0055] 3. Finally the sample S x′, y′, z′ is calculated as:
S x′, y′, z′ =T x, y′, z′ +W x ( T (x+1), y′, z′ −T x, y′, z′ )
[0056] It will be noted that the samples S x′, y′, z′ are organized in planes parallel to one face of the volume data set 10 , and also that the samples are organized in rectangular arrays whose sides are parallel to the axes of the volume data set 10 . Accordingly, it will be appreciated that during the calculation of samples within neighboring groups of 8 voxels, some of the intermediate values U and T described above can be re-used. For example, the intermediate values T x, y′, z′ and T (x+1), y′,z′ can be used to calculate sample values S (x′−1), y′, z′ and S (x′+1), y′, z′ respectively. These intermediate results are thus passed among calculation elements using FIFO elements in order to maximize processing bandwidth.
[0057] The term “supersampling” refers to the calculation at sample points with a spacing less than the spacing between voxels in a given dimension. Equivalently, it refers to the re-sampling of volume data at spatial frequencies greater than the spatial frequency of the voxels themselves. Supersampling may be desirable to reduce visual artifacts that could be created by re-sampling at a lower spatial frequency. For example, it will be appreciated that when the view direction is not exactly parallel to the Z axis, the distance between voxel slices as measured along the lengths of the rays is greater than that prescribed by the Nyquist frequency and therefore visual artifacts are likely to appear. Supersampling in either the X or Y dimension can be accomplished by setting the spacing between the rays 18 to less than the spacing between voxels 12 in the X-Y plane. Supersampling in the Z dimension can be accomplished by creating “virtual slices” of sample points whose spacing in the Z dimension is specified to be less than the spacing between the slices 230 of voxels 12 . The spacing between virtual slices may be an integer sub-multiple of the spacing of voxel slices 230 , but in general the spacing can be specified as an arbitrary fraction of the spacing between voxel slices 230 . The spacing between virtual slices should be small to obtain desired fidelity, but this goal must be balanced with the need for more buffering and greater calculation precision as the spacing decreases.
[0058] In the illustrated embodiment, the spacing of the rays 18 in the X and Y dimensions is always the same as the spacing of the voxels 12 . Thus the illustrated processing element 210 does not perform supersampling in the X and Y dimensions. In the illustrated embodiment, the effect of X and Y supersampling can be achieved by performing multiple renderings of the dataset 10 each with slightly different X and Y offsets, and then interleaving the resulting renderings in software.
[0059] In the illustrated embodiment, the virtual slices are created by first obtaining a slice of Z-interpolated values U, as described above. From the U values, Y-Z interpolated values T are obtained, and then finally the X-Y-Z interpolated values (or samples) S are obtained from the T values. This is one form of tri-linear interpolation. As previously mentioned, other forms of interpolation such as LaGrangian can alternatively be used. The illustrated technique can be applied to supersampling in the X and Y dimensions also. Because of the order in which the interpolations are performed, the intermediate values U and T can advantageously be reused during the calculations for neighboring samples. Strictly speaking, one tri-linear interpolation requires 7 multiplies and 14 adds, but by this technique, each sample is obtained using only 3 multiplies and 6 adds.
[0060] [0060]FIG. 8 shows that the X and Y components of the gradient of a sample, G x x′, y′, z′ and G y x′, y′, z′ are each estimated as a “central difference”, i.e., the difference between two adjacent sample points in the corresponding dimension. Thus as shown
G
x
x′, y′, z′
=S
(x+1), y′, z′
−S
(x′−1), y′, z′
[0061] and
G
y
x′, y′, z′
=S
x′,(y′+1), z′
−S
x′, (y′−1), z′
[0062] It will be appreciated that the calculation of the Z component of the gradient (also referred to herein as the “Z-gradient”) G z x′, y′, z′ is not so straightforward, because in the Z direction samples are offset from each other by an arbitrary viewing angle. Another complicating factor, discussed below, is whether supersampling is used. It is possible, however, to greatly simplify the calculation of G z x′, y′, z′ when both the gradient calculation and the interpolation calculation are linear functions of the voxel data (as in the illustrated embodiment). When both functions are linear, it is possible to reverse the order in which the functions are performed without changing the result. The Z-gradient is calculated at each voxel position 12 in the same manner as described above for G x x′, y′, z′ and G y x′, y′, z′ , and then G z x′, y′, z′ is obtained at the sample point x′, y′, z′ by interpolating the voxel Z-gradients in the Z direction.
[0063] [0063]FIG. 9 shows the portion of the processor of FIG. 5 that performs the gradient and interpolation calculations. A set of slice buffers 240 is used to buffer adjacent slices of voxels from the voxel memory 100 , in order to time-align voxels adjacent in the Z direction for the gradient and interpolation calculations. The slice buffers 240 are also used to de-couple the timing of the voxel memory 100 from the timing of the remainder of the processing unit when Z-axis supersampling is employed, a function described in greater detail below. A first gradient estimation unit 242 calculates the Z-gradient for each voxel from the slice buffers 240 . A first interpolation unit 244 interpolates the Z-gradient in the Z direction, resulting in four intermediate values analogous to the U values described above. These values are interpolated in the Y and X directions by interpolation units 246 and 248 to yield the interpolated Z-gradient G z x′, y′, z′ . Storage elements not shown in FIG. 9 are used to temporarily store the intermediate values from units 244 and 246 for interpolating neighboring Z-gradients in a manner like that discussed above for samples.
[0064] The voxels from the slice buffers 240 are also supplied to cascaded interpolation units 250 , 252 and 254 in order to calculate the sample values S x′, y′, z′ . These values are used by the classification unit 120 of FIG. 5, and are also supplied to additional gradient estimation units 256 and 258 in which the Y and X gradients G y x′, y′, z′ and G x x′, y′, z′ respectively are calculated.
[0065] As shown in FIG. 9, the calculation of the Z-gradients G z x′, y′, z′ and the samples S x′, y′, z′ proceed in parallel, as opposed to the sequential order implied by FIG. 5. This structure has the benefit of significantly simplifying the Z-gradient calculation, as previously mentioned. As another benefit, calculating the gradient in this fashion can yield more accurate results, especially at higher spatial sampling frequencies. The calculation of central differences on more closely-spaced samples is more sensitive to the mathematical imprecision inherent in a real processor. However, the benefits of this approach are accompanied by a cost, namely the cost of three additional interpolation units 244 , 246 and 248 . In alternative embodiments, it may be desirable to forego the additional interpolation units and calculate all gradients from samples alone. Conversely, it may be desirable to perform either or both of the X-gradient and Y-gradient calculations in the same manner as shown for the Z-gradient. In this way the benefit of greater accuracy can be obtained in a system in which the cost of the additional interpolation units is not particularly burdensome.
[0066] [0066]FIG. 10 illustrates the writing and reading of the slice buffers 240 when super-sampling is not used. In this case, only one sample and gradient are calculated per voxel per slice 230 . FIG. 10 shows that two slice buffers are loaded simultaneously (i.e., (0, 1), (2, 3) etc.), and the pairs of slice buffers are loaded in a sequential, round-robin fashion. The line labelled EMPTY SB indicates which slice buffers are considered empty at a given time, meaning that they do not contain data that will be read out to the processing element imminently. The line labelled READ SB indicates which four slice buffers are being read at a given time. As shown, the slice buffer sets are read in a sequential, round-robin fashion.
[0067] [0067]FIG. 11 illustrates the writing and reading of the slice buffers 250 when super-sampling at a spatial frequency of about twice the voxel spatial frequency is used. In this case, two samples and gradients are calculated per voxel per slice 230 . Each set of four slice buffers is read out twice, once for each sample-gradient pair calculated by the processing element. Stepping in the Z direction is indicated by the toggling STEP Z signal. Initially, the six slice buffers 240 are filled for three successive slice fetches, and then subsequently emptied and re-filled at half the initial rate, as indicated by the signal fetchSlice. It will be appreciated that for different supersampling frequencies the write and read rates are changed accordingly. Because the flow rate of voxels from voxel memory 100 is diminished when super-sampling is used, the effective image rendering rate rendered is likewise reduced. Thus in the illustrated case of approximately 2 × supersampling, the rendering rate is reduced to approximately 15 frames per second.
[0068] It will be appreciated that in alternative embodiments in which supersampling in either or both the X and Y directions is employed, buffering must be used at intermediate points 260 , 262 , 264 and 266 in the processing element of FIG. 9. Such buffering performs a function analogous to that performed by the slice buffers 240 , namely decoupling the timing of successive stages in order to allow for multiple samples and gradients to be calculated per pair of adjacent beams or individual values. Beam buffers are required at points 260 and 264 to provide the necessary de-coupling for supersampling in Y, and sample buffers are required at points 262 and 266 to provide the necessary de-coupling for supersampling in X.
[0069] It should be noted that because supersampling reduces the distance between samples, it may decrease the accuracy of gradient calculations obtained by central differences. For this reason, it may be desirable to employ the described technique of calculating gradients on voxels and then interpolating the result in any dimension in which sufficiently high-frequency supersampling is used.
[0070] [0070]FIG. 12 shows the structure of the weight generator 90 of FIG. 9, which is used to provide the previously-described weights w z , w y , and w x used by the various calculation units. A differential data analyzer (DDA) algorithm is used to continually generate updated weights as the processor steps through the volume data. The weights w z , w y , and w x indicate the position of a sample S x′, y′, z′ relative to a voxel V x, y, z, where
x≦x′≦x+l, y≦y′≦y+l, and z≦z′≦z+l 1
[0071] and where
x′=x+w x , y′=y+w y , and z′=z+w z 2
[0072] Note that while voxels 12 have integer coordinates in XYZ space, sample points 20 in general have non-integer coordinates. The weight generator 90 is programmed with step sizes stepX for the X dimension, stepY for the Y dimension and stepZ for the Z dimension. These step sizes are derived by controlling software from the orientation of the view axis, and hence of the rays 18 , with respect to the X, Y and Z coordinate axes.
[0073] Three identical weight calculation units 280 are used, one per X, Y and Z dimension. Each unit 280 receives an initial value (e.g. initialZ) and a step size (e.g. StepZ). Each unit 280 includes a weight accumulator. The step sizes are repeatedly accumulated by the accumulators within the calculation units 280 as samples are calculated. During each step, a new weight is calculated and rounded to 8 bits of precision; it will be appreciated that additional bits of precision are carried to prevent accumulation errors from exceeding an acceptable level. The rounded weight outputs w x , w y and w z . are supplied to the interpolation units shown in FIG. 9.
[0074] The accumulator for the X dimension counts up to its maximum value as voxels 12 within a beam 232 are processed, and the accumulator for the Y dimension counts up as beams 232 within a slice 230 are processed. The accumulator for the Z dimension counts up as virtual slices within the data set 10 are processed. The precision of these step sizes is 19 bits to the right of the binary point.
[0075] The step outputs stepX, stepY, and stepZ from the weight generator 90 are used to count samples for control purposes, such as controlling the slice buffers 250 as described above. It will be appreciated that in the illustrated embodiment the signals stepX and stepY are incremented by one during each sampling step in the corresponding dimension, whereas the signal stepZ increments only when a sampling step crosses the boundary of the next slice 230 . This occurs every z-step if supersampling is not enabled, but when supersampling is used then it occurs at a rate inversely proportional to the supersampling factor.
[0076] A ray-casting volume rendering system employing supersampling of the volume dataset has been described. It will be apparent to those skilled in the art that modification to and variation of the above-described methods and apparatus are possible without departing from the inventive concepts disclosed herein. Accordingly, the invention should be viewed as limited solely by the scope and spirit of the appended claims. | A volume rendering processor renders a two-dimensional image from a volume data set of voxels constituting a three-dimensional representation of an object. Voxel memory interface logic retrieves the voxels from a voxel memory in a scanned order with respect to X, Y and Z coordinate axes, the Z axis being the axis most nearly parallel to a predefined viewing direction. The set of voxels having equal Z coordinate values are referred to as a “slice” of voxels. Interpolation logic calculates a sequence of samples from the retrieved voxels such that (i) each sample lies along a corresponding imaginary ray extending through the object parallel to the viewing direction, (ii) each sample results from interpolating the eight voxels surrounding the sample in the XYZ coordinate system. “Supersampling” in the Z dimension is performed such that the number of samples calculated for each ray is greater than the number of slices of voxels in the volume data set. Gradient calculation logic calculates for each sample respective gradients in the X, Y and Z directions for use by classification and illumination logic. The X and Y gradients are calculated from the samples emitted by the interpolation logic, and Z gradients are calculated by (i) calculating Z gradients at the voxel positions from voxel values retrieved from memory, and (ii) interpolating the voxel Z gradients to arrive at the Z gradients at the sample positions. | 6 |
FIELD OF THE INVENTION
The present invention relates to a gas bearing for a rapidly rotating tool, in particular an aerostatic bearing of a spinning rotor, which cannot be overloaded by the occurring forces, such as unbalancing forces, and which runs in the supercritical range.
BACKGROUND OF THE INVENTION
In the prior art, primarily a conventional and proven twin disk bearing (roller bearing) was used as the bearing of a spinning rotor. In this case, the spinning rotor is at the end of a shaft which runs between a drive belt and two rollers which have diameters at least 10 times greater than the diameter of the shaft and which are lined with rubber. In view of this translation ratio of 1:10, the life of the ball bearing could be extended considerably over that of a direct ball bearing of the spinning shaft, where a 10 times greater speed of the ball bearings is necessary. Nevertheless, the rollers and the ball bearings must be renewed approximately every 20,000 hours because of wear.
The twin disk bearing offers however clear advantages over earlier bearings. Specifically, since it is able to bear relatively great loads and because of the rubber lining on the rollers and the drive via a belt, the shaft with the spinning rotor runs in the supercritical range, so that the unbalance forces exerted upon the bearing are considerably lower. This bearing is described in detail in the document laid open to public inspection, German Patent Application No. DE 25 25 435 B1. In the apparatus described in this document, a support bearing (see column 4, uppermost paragraph) is also present, but in an entirely different context from that of the bearing designated at 4 and described in the claims.
Furthermore, in this connection the use of aerostatic bearings has often been tried, as no wear of the bearing occurs with them. As the document laid open to public inspection German Patent Application No. DE-AS 23 49 072 describes, the rotor is rigidly connected to the supported shaft in this case, and therefore this bearing is unable to support the high loads caused by unbalance in the spinning rotor when a yarn breakage occurs.
Where varnish atomization is used, for example, and in spite of the aerostatic bearing which is often used, rigid connection between the atomizer and the rotating shaft is still customary, so that low unbalance masses or a slightly eccentric seat of the atomizer on the shaft can already cause the aerostatic bearing to become overloaded. Since the ability of gas bearings to bear loads as compared to roller bearings of the same size is many times lower, their utilization was often not possible until now. Furthermore, even a slight overload of the gas bearing at high rotational speeds causes irreparable malfunction.
In addition to spinning rotors, a gas bearing is desirable also with other rapidly rotating tools. Such tools are for example the head of a varnish atomizers, the drum of a centrifuge and optical tools such as prisms, polygons etc. Instead of air, other gases can and should also be used for the bearing. The bearing should and can be static or dynamic.
OBJECTS AND SUMMARY OF THE INVENTION
A motivating object of the invention was thus to create a gas bearing for a rapidly rotating tool, in particular an aerostatic bearing of the spinning rotor, which cannot be overloaded by the occurring forces, such as unbalance forces, and which runs in the supercritical range. After many attempts, it was found that a wide bearing gap (in the range of 1/10 mm) is necessary for this; however this leads to high air consumption, so that the energy costs are unsustainable. Then a possibility was sought of ensuring supercritical bearing of the spinning rotor in spite of the narrow bearing gap (8-12 μm). Elastic suspension of the bearing rings (or bearing cups) in O-rings made it possible to obtain supercritical operation, but because the air bearing gap lies within the oscillation range and must therefore transmit the inertia compensation forces, the necessary absorption of unbalance forces could not be ensured in this case.
Supercritical suspension of the spinning rotor itself in the aerostatically supported shaft was considered then as a last possibility. For this, the spinning rotor was suspended on a freely oscillating extension (e.g., an extension rod) of such dimensions that it was possible already at low rotational speeds to pass through the first natural oscillation (oscillation resonance). The oscillation amplitudes when passing through the resonance were however so high that the aerostatic bearing was overloaded. A bearing at the end of the extension with sufficient clearance in order to make free oscillation of the extension in the supercritical range of rotational speed possible finally solved the problem. This bearing only becomes functional when the oscillation amplitudes at the end of the extension with the spinning rotor are greater than the clearance of the bearing. As soon as the spinning rotor runs in the supercritical range, contact between bearing and extension must be excluded, and for this, at least twice the bearing clearance of the aerostatic radial bearing is required for this bearing. With this suspension of the spinning rotor, it was possible to create an aerostatic bearing which cannot be overloaded by unbalance forces, in addition to the advantage of low wear.
In order to shorten the length of the spindle and bring the unbalance forces emanating from the spinning rotor closer to the aerostatic bearing, the oscillation-free extension is installed for the major part in a centered bore of the aerostatically supported shaft. To ensure that the extension passes through the first natural oscillations already at low rotational speeds, the length of the extension must be at least about four times the smallest diameter of the extension. Since the second natural oscillation of the extension must be far enough from the operating speed, the diameter of the extension must increase from the point of connection to the spinning rotor.
Attachment of the extension in the bore of the shaft represents another problem. At first threads were used, but this caused loosening due to settling phenomena in the threads after a certain time of operation because of the high dynamically alternating stress. A press fit was extremely costly because the pressing had to be produced with very narrow dimensional tolerances (about 5 to 10 μm) in order to prevent bending the extension because of excessive press forces. By providing threads on either the extension or the shaft, the insertion force could still be within acceptable ranges with wide dimensional tolerances of about 1/10 mm, without having to fear a bending of the extension.
Replacement of the spinning rotor must be possible also with aerostatic bearings. For this reason, a detachable connection between the shaft and spinning rotor was provided in the design up to now. However, this had as a consequence that the spindle had to be balanced again each time the spinning rotor was replaced, or a high-precision, expensive fit between shaft and spinning rotor had to be provided (tolerance field width of about 0.002 mm) because the unbalance exceeds the limit load of the aerostatic bearing even with slightly eccentric seating of the spinning rotor.
By providing the detachable connection at the end of the above-mentioned extension of the aerostatically supported shaft, the connection can be established with wider tolerance (about 0.05 mm), since it lies within the supercritical range of oscillation which is attained already at relatively low rotational speed.
In some applications, it was then necessary to provide a bore in the extension, through which something can be inserted (e.g., varnish, cotton fibers, etc.). For this, a certain minimum diameter is indicated here, and free oscillation is produced by ensuring that the wall of the extension is suitably thin between the press fit of the shaft and the bearing of the extension.
It was then found that an additional radial bearing at the free end of the drive element considerably increases the radial ability of the aerostatic bearing to bear loads. In order to continue providing a wear-free bearing unit, it is advisable to use an aerostatic bearing as the additional radial bearing. This centered arrangement of the drive element between the two aerostatic bearings leads to a load free of breakdown torque. For this reason, a uniform narrowing of the bearing gap is produced over the entire length of the bearing, and an advantageous distribution of pressure is created, enabling the aerostatic bearing to bear much greater loads.
For technical reasons in manufacture, it is advantageous to make the part of the shaft born or retained in the radial bearing at the free end of the drive element and the freely oscillating extension at the end of which the spinning rotor is attached, as a single integral part. In order to attach the portion of the shaft supported between the spinning rotor and the drive element to the rear portion of the shaft, an advantageous press-fit connection is provided near the drive element.
In one embodiment of the present invention, the two aerostatic axial bearing through which a flow goes from the larger bearing diameter to a smaller inside diameter are located at the end of the shaft. In order to reduce the friction of the radial bearing, the bearing diameter must be made smaller, and this created the problem that the axial bearing carried out auto-stimulated axial oscillations. For this reason, it is advantageous to provide a disk at one end of the shaft to serve as bilateral axial bearing of the shaft. Depending on the manufacturing or assembly process, it is advantageous for the shaft and the disk to be made in one piece, or to connect them to each other by means of a press-fit or welded connection.
By attaching a ring-shaped permanent magnet on one side, which is arranged to exert a force of attraction on the disk at the end of the shaft, one of the two aerostatic axial bearings can be omitted, and this may be an advantage in manufacture, depending on the configuration.
The pressure force of the belt against the drive element deforms the shaft. It was found that the aerostatic bearings offer the highest load capacity when the deformation of the connecting element of the bearing is adapted to the deformation of the shaft in the area of the drive element, since uniform narrowing of the bearing gap over the entire length of the bearing of the radial bearing in question is then ensured. To be able to achieve this, the two aerostatic bearings must be suspended individually in the spindle housing in such manner that they are able to assume an inclined position relative to the longitudinal axis of the spindle without meeting with resistance. Membrane-like elements or an elastic suspension by O-rings are suitable for this.
Since the diameter and the length of the drive element are prescribed in advance, the connecting element of the aerostatic radial bearing must be adapted in its geometric dimensions such as length, width and height so that the connecting element of the bearings and the drive element of the shaft have nearly the same deflection with a given load imposed by the pressure force of the belt.
In one embodiment of the invention, the detachable connection for the replacement of the spinning rotor is attached at the end of the freely oscillating extension. A special embodiment which makes it possible to replace the spinning rotor rapidly is now described here in greater detail.
A snap connection producing a connecting force through elastic deformation of the connecting element is especially well suited. A ring made of spring steel is a suitable elastic connecting element. In order to ensure clearance-free seating of the rotor, the connection point should be conical in form. A slit in the circumference of the ring provides for greater elasticity, so that more favorable manufacturing tolerances of the connection are possible. It is an additional advantage of this connection which uses a ring, that the centrifugal forces which occur cause the ring to widen, so that the connection is given additional holding strength in a dynamic state.
It was found to be useful to use the disk serving for an axial bearing in addition to brake the shaft. In such a case, by attaching a ring-shaped extension at the edge of the disk, a radial gap is formed together with the housing, whereby a liquid is pressed through a bore into the gap so that the liquid friction brakes the shaft hydrodynamically.
Another possibility consists in braking the disk by means of a ring-shaped brake lining which is attached in the housing and can be shifted. The pressure force for this brake lining may be produced mechanically, elector-magnetically or pneumatically. In a pneumatically actuated brake, the brake lining is suspended by O-rings in the housing so that a seal against the space in the housing which is supplied compressed air through a bore may be created. The resetting of the brake lining, achieved through the thrusting forces in the O-rings, is an advantage of this arrangement, so that the lining no longer rubs against the disk upon completion of the braking process.
In another embodiment, the shaft comprises a central bore in which the extension rod is situated and the extension rod is coupled to the shaft at an end opposite to the end at which the tool, e.g., spinning rotor, is attached. The extension rod is drilled at the shaft-coupling end and press-fit connection means are provided for attaching the drilled end of the extension rod to the shaft. A thickness of a wall of the extension rod increases in direction from the drilled end to the tool-attaching end.
BRIEF DESCRIPTION OF THE DRAWINGS
The following drawings are illustrative of embodiments of the invention and are not meant to limit the scope of the invention as encompassed by the claims.
FIG. 1 shows a first embodiment of a spindle for a gas bearing for a rapidly rotating tool in accordance with the invention.
FIG. 2 shows a second embodiment of a spindle for a gas bearing for a rapidly rotating tool, which is a varnish atomizer in this embodiment, in accordance with the invention.
FIG. 3 shows a third embodiment of a spindle for a gas bearing for a rapidly rotating tool in accordance with the invention.
FIG. 4A shows an embodiment of the snap according to the invention which is used to connect the spinning rotor to an end of an extension rod.
FIG. 4B is a cross-sectional side view of the ring shown in FIG. 4A.
FIG. 4C is a frontal view of the ring shown in FIGS. 4A and 4B showing the slit therein.
FIG. 5 shows an embodiment of a hydrodynamic braking device used in conjunction with the spindle in accordance with the invention.
FIG. 6 shows another embodiment of a braking device used in conjunction with the spindle in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the accompanying drawings, the spindle in accordance with the invention as shown in FIG. 1 comprises a housing 8, an elongate, substantially cylindrical shaft 5 aerostatically supported in the housing 8 in both an axial and radial direction. The designs of aerostatic bearings are known in the art. The aerostatic bearing used here stands out because of its low air consumption, since the exhaust air used in the radial bearings is also used in the axial bearings. Air or another gas is introduced into the housing in the direction of arrow A 1 and flows in a clearance 11 defined between the housing 8 and the outer peripheral surface of the shaft 5, to function as a radial aerostatic bearing, and then between end surfaces of the shaft 5 and the housing 8, to function as an axial aerostatic bearing.
The shaft 5 is driven at one end 7 via drive means such as a tangential belt. A central bore is located in the shaft 5 at a side opposite end 7. An extension 2, which is also referred to as an extension rod, is attached at one end in a bottom of the bore in the shaft 5 by connection means such as a press-fit connection 6. The extension 2 is in form of a rod which is connected at an end opposite to the end attached to the bottom of the bore in shaft 5 to a spinning rotor 1, e.g., by means of a screw connection. The press-fit connection 6 between rod 2 and the bottom of the bore in shaft 5 is established through the fact that at least one of the rod 2 and the bore in shaft 5 is provided with threads T1, T2 (the press measure is about 0.2 mm to about 0.3 mm). The diameter of rod 2 increases in steps in the direction of the spinning rotor 1, i.e., it is smaller at the end connected to the bottom of the bore in shaft 5 than at the end to which the rotor 1 is connected. The smallest diameter near the location of the connection 6 between shaft 5 and rod 2 must be of such size as to be able to transmit with sufficient reliability the drive and brake moments to the spinning rotor 1, and must be small enough so that the first natural vibration of the rod 2 can be run through even at a relatively low rotational speed (it measures about 3 mm in this embodiment). The overall length of the rod 2 is approximately 20 times the smallest diameter.
At the end of the rod at which the spinning rotor 1 is attached, there is an additional radial bearing 4 with a bearing clearance 10 which is about ten times the clearance 11 of the aerostatic radial bearing, i.e., the distance between the outer peripheral surface of the shaft 5 and the opposed inner surface of the housing 8. This clearance 10 should be at least two times clearance 11. This bearing 4 is a grease-lubricated sliding bearing in the illustrated embodiment. A roller bearing with sufficient bearing clearance could be used as well. In order to achieve good damping of the bearing as the first natural vibration is run through, the sliding bearing 4 is suspended on O-rings 3 in the housing.
Since the spinning rotor 1 must be replaced every 10,000 hours of operation for reason of wear, it is no great effort to replace the greased and partly worn sliding bearing 4 at the same time. At this point in time, information is not yet available on the actual life of the sliding bearing 4.
The spindle is designed for a rotational speed of about 120,000 RPM. The first natural vibration of the rod 2 is run through already at a rotational speed of about 12,000 RPM. Thereafter, the spinning rotor runs in the supercritical vibration range, i.e., the inertia forces are always compensated for, and the forces exerted on the aerostatic bearing are low, even in the presence of great unbalance. The spinning rotor operates in the subcritical zone up to about 11,000 RPM.
Referring now to the embodiment of the spindle in accordance with the invention as shown in FIG. 2, the spindle comprises a shaft 5 supported aerostatically in a radial direction in a housing 8 by the inflow of air or another gas in the direction of arrow A 1 into the housing and between an outer peripheral surface of the shaft 5 and the housing 8. Shaft 5 has an outwardly directed flange at one end thereof. The axial bearing comprises a combination of a permanent magnet 12 arranged in a position opposite the flange of the shaft 5 and the unilaterally effective aerostatic axial bearing which is provided with air coming from the radial bearing gap, i.e., the passage of air through a clearance between the flange of the shaft 5 and the housing 8. The configurations of aerostatic bearings are known in the state of the art. The aerostatic bearing used here stands out in particular because of low air consumption.
The shaft 5 is driven at its flanged end via drive means such as an air turbine 9 into which air is directed in the direction of arrow A 2 . Shaft 5 includes a central bore and an extension 2 is attached to the inner circumferential surface at one end of the bore in shaft 5 by connection means such as a press-fit connection 6. A block 7 is arranged at the flanged end of the shaft 5 to surround the flange of the shaft 5.
The extension 2 is made in form of a substantially cylindrical pipe rod at the end of which a varnish atomizer 1 is attached by connecting means such as a screw connection. The varnish is passed to the atomizer 1 through the hollow interior of the shaft 5 in the direction of arrow A 3 . The wall 13 of extension rod 2 is extremely thin between the location of the press-fit connection 6 and the location opposed to a bearing 4 of the extension rod 2 (about 0.08 mm) so that sufficient elasticity of the freely oscillating extension rod 2 may be ensured so that the natural vibration may be run through already in the speed range from about 6,000 to about 8,000 RPM. The thickness of the wall 13 of extension rod 2 increases again considerably in the direction of the end towards the varnish atomizer 1 in order to make support and detachable installation of the same possible. Thus, the extension rod 2 has a variable thickness.
The bearing 4 at the end of extension rod 2, where the varnish atomizer 1 is attached, has a clearance 10 which is ten times the bearing clearance 11 of the aerostatic bearing which in this case has a clearing of about 20 μm. This bearing 4 is in this case an oil-soaked sintered bronze sliding bearing. A roller bearing with sufficient bearing clearance could just as well be used. In order to achieve good damping of the bearing 4 as the first natural vibration is run through, the bearing 4 is suspended on O-rings 3 in the housing.
The spindle is designed for an operating speed of about 80,000 RPM. The first natural vibration of the extension rod 2 is run through already at about 7,000 RPM. Afterwards, the varnish atomizer 1 runs in the supercritical vibration zone, i.e., the inertia forces in the atomizer 1 are constantly compensated for and the forces exerted upon the aerostatic bearing are low, even when great unbalance masses are present.
FIG. 3 shows another embodiment of the spindle bearing in accordance with the invention when applied in connection with a spinning rotor 1. The spinning rotor 1 is attached at the end of a freely oscillating extension 2 by means of a detachable connection. A sliding bearing 7 surrounds a portion of the extension 2 proximate to the end attached to the rotor 1 and limits the vibration excursions as the first natural vibration of the extension 2 is run through.
The housing 15 of the spindle includes a shaft which is supported aerostatically in radial and axial directions in the housing which comprises two bearing elements 3,5 which are connected to each other by a drive element 4. A flat belt 16 exerting radial forces runs over the drive element 4. The two bearing elements 3,5 of the shaft are coupled to each other by connecting means such as a press-fit connection 13 in the area of the drive element 4. The rear bearing portion of element 5 and the freely oscillating extension 2 are made in one part, i.e., integral with one another. On the rotor side of the shaft adjacent element 3, a disk 10 is attached by press-fit and is used for axial support in both directions. Each of two bearing housing elements 6,11 which house elements 5,3, respectively, comprises a bushing 8 into which two rings are pressed and between which a gap exists which is needed for the air supply of the aerostatic radial bearing. Each bearing element 6,11 has an air connection (represented by arrows A 1 ). The connecting element 12 of the two bearing elements 6,11 is configured in its geometry so that it is closely adapted to the load-dependent deformation of the drive element 4. The bearing elements 6,11 and the connecting element 12 are made in one piece, i.e., integral with one another, in the illustrated embodiment. Each bearing element 6,11 is attached on an O-ring 14 in the spindle housing 15. A bushing 9 is press-fitted into the forward bearing element 11 and is provided to support the axial bearing. The above-described sliding bearing 7 is suspended in this bushing by means of O-rings.
FIG. 4A shows an embodiment of the snap according to the invention which is used to connect the spinning rotor 1 to the end of the freely oscillating extension 2. A groove 25 is located on the conical end of the extension 2 and an elastically deformable ring 23 is inserted into the groove 25 (the ring being shown more clearly in FIG. 4B). The seat at the spinning rotor 1 is formed by two opposing cones which meet at the snap edge 26. In order to achieve greater elasticity of the ring 23, the ring circumference 24 is slit at one location (FIG. 4C).
FIG. 5 shows an embodiment of a hydrodynamic braking device used in conjunction with the spindle in accordance with the invention whereby an axially supported disk at the end of the shaft is used. A ring-shaped extension 34 is attached to the edge of a disk 35 which is flanged from a shaft 36 and provides axial support for the shaft 36. This extension 34, together with a portion of the brake housing 31, define a radial gap 33. Oil is pressed into this gap 33 through a bore 32. Liquid friction brakes the shaft 36 and the spinning rotor 1 until they stop. The ring-shaped extension 34 has a ratio wall thickness to width of at least 1:2.
FIG. 6 shows another embodiment of a braking device used in conjunction with the spindle in accordance with the invention whereby an axially supported disk at the end of the shaft is used. The embodiment in FIG. 6 includes a pneumatically operated friction lining brake. In this brake, a disk 45 flanged from the shaft 46 and used for axial support of the shaft 46 is also used. A brake lining 44 is pressed on an axial surface on one side of the disk 45. The brake lining 44 is attached in the brake housing 41 by means of O-rings 43 so as to be capable of shifting. The brake lining 44 with the O-rings 43 and the brake housing 41 define a space which is supplied with compressed air via a bore 42 during braking. The axial force opposing the brake pressure is produced by the aerostatic axial bearing.
The examples provided above are not meant to be exclusive. Many other variations of the present invention would be obvious to those skilled in the art, and are contemplated to be within the scope of the appended claims. | A spindle for gas bearing of a rapidly rotating tool, in particular for aerostatic bearing arrangement of an open-end spinning rotor, including a spindle housing, a rotatable elongate shaft supported in the spindle housing in a radial direction of the shaft by a radial gas bearing element and an elongate extension rod. The rotor is coupled to the extension rod at a first end thereof. An extension rod bearing element is arranged at a region proximate the first end of the extension rod at which the rotor is attached. A first bearing clearance is defined between the radial bearing element and the shaft and a second bearing clearance is defined between the extension rod and the extension rod bearing element which is at least twice the first bearing clearance. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a 371 National Stage Application claiming priority to PCT Application No. PCT/EP2011/067432 filed Oct. 6, 2011, which claims priority to Great Britain Application No. 1016822.7 filed Oct. 6, 2010, now GB Patent 2484317 issued Mar. 20, 2013, and Great Britain Application No. 1019000.7 filed Nov. 10, 2010, now GB Patent 2484354 issued Feb. 6, 2013, the technical disclosures of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to an apparatus for and method of heating an operating fluid, and has particular application in a frying method and a frying apparatus which have high energy efficiency, and low waste heat.
2. Description of Related Art
The present invention has particular application in the manufacture of snack foods, more particularly potato chips.
In many industrial processes there is a need to heat an operating fluid, and there is a general desire to provide energy efficient processes, having minimum carbon footprint, to achieve that heating. For example, frying processes are commonly used to produce a variety of different fried foodstuffs. Frying is particularly used to cook snack food products such as potato chips. In potato chip manufacture, cut slices of raw potato are cooked in a fryer containing cooking oil at an elevated temperature. Energy is required to heat the oil and maintain it at the desired cooking temperature. In addition, the frying process dehydrates the potato slices and a large volume of steam is generated which is typically captured by a hood disposed over the fryer and exhausted to the atmosphere, or the steam is passed into a thermal oxidiser for volatile destruction.
There is a generally recognised desire in the snack food manufacturing art to reduce the energy costs and waste heat generation of the frying apparatus. However, it is also necessary to ensure that the frying process and apparatus still produce a high quality product to the consumer which meets customer acceptance and is reliably and consistently achievable despite high production volumes. In particular, potato chips are normally required to meet very strict customer acceptance criteria for the respective product, for example having specific moisture and oil-in-chip contents, and the desired taste, organoleptic and other sensory attributes.
SUMMARY OF THE INVENTION
The present invention aims to provide an apparatus for and method of heating an operating fluid, which may have particular application in a frying method and a frying apparatus, which have high energy efficiency and low generation of waste heat. Such an apparatus and method have particular application for frying foodstuffs, such as snack foods and most particularly potato chips, to provide enhanced energy efficiency and reduced waste heat, in particular reduced waste steam production.
The present invention accordingly provides an apparatus for heating an operating fluid, the apparatus comprising a closed circuit for a working fluid, the closed circuit having first and second heat exchangers and a compressor therebetween, the first heat exchanger having a heat input side for connection to an external fluid heat source and a heat output side for vaporising working fluid within the closed circuit, the compressor being a vapour compressor adapted to compress the vaporised gaseous working fluid from the first heat exchanger to form a higher pressure gaseous working fluid, and the second heat exchanger having a heat input side for receiving and condensing the higher pressure gaseous working fluid from the compressor and a heat output side for heating an external operating fluid.
Preferably, the apparatus further comprises an oil recirculating system coupled to a fryer for frying foodstuffs, wherein the heat output side of the second heat exchanger is connected to the oil recirculating system, the fryer oil comprising the external operating fluid.
Optionally, the apparatus yet further comprises a hood above the fryer, the heat input side of the first heat exchanger being connected to the hood, the hood being adapted for collecting steam generated during the frying process, the steam comprising the external fluid heat source.
Typically, the fryer has inlet and outlet ends connected to the oil recirculating system.
The apparatus may further comprise a gas-powered engine for driving the compressor.
The apparatus may yet further comprise a third heat exchanger for heating the external operating fluid, the gas-powered engine having an exhaust for combustion gases connected to the third heat exchanger.
Optionally, the apparatus further comprises an electrical generator connected to the gas-powered engine to generate electrical power to drive the compressor.
Typically, the gas-powered engine is a gas turbine.
The apparatus may further comprise a tank for collecting from the first heat exchanger condensed fluid of the external fluid heat source.
The present invention also provides a method of heating an operating fluid, the method comprising the steps of:
i. vaporising a working fluid in one side of a first heat exchanger of a closed circuit by heat input from an external fluid heat source in an opposite side of the first heat exchanger; ii. conveying the vaporised gaseous working fluid around the closed circuit to a vapour compressor; iii. compressing the vaporised gaseous working fluid in the vapour compressor to form a higher pressure gaseous working fluid; iv. conveying the higher pressure gaseous working fluid around the closed circuit to a second heat exchanger of the closed circuit; v. condensing the higher pressure gaseous working fluid in one side of the second heat exchanger, thereby heating an external operating fluid on an opposite side of the second heat exchanger; and vi. conveying the condensed working fluid around the closed circuit to the first heat exchanger.
The method is preferably used in a method of frying foodstuffs in a fryer which employs recirculated fryer oil from the fryer as the external operating fluid. The external fluid heat source may comprise steam generated during the frying process. Typically, the fryer has inlet and outlet ends coupled to an oil recirculating system. The foodstuffs may comprise snack foods, optionally potato chips.
Preferably, the vapour compressor is driven by a gas-powered engine.
Optionally, the gas-powered engine has an exhaust for combustion gases and the exhaust is connected to a third heat exchanger for heating the external operating fluid.
The gas-powered engine may be connected to an electrical generator for generating electrical power to drive the compressor. The gas-powered engine may be a gas turbine.
The method may further include the step of collecting condensed fluid of the external fluid heat source from the first heat exchanger.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic illustration of a frying apparatus incorporating an apparatus for heating an operating fluid in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 , there is shown a frying apparatus incorporating an apparatus for heating an operating fluid in accordance with a first embodiment of the present invention. A fryer 2 is a continuous fryer in which foodstuffs, typically snack foods such as potato chips, to be fried are fed in at one upstream longitudinal end 4 of the fryer 2 and the cooked foodstuff is removed at the opposite downstream longitudinal end 6 of the fryer 2 . Correspondingly, the cooking oil flows continuously along the fryer 2 from the upstream or inlet end 4 to the downstream or outlet end 6 . A conveyor 7 for removing fried foodstuffs from the oil in the fryer 2 is disposed at the outlet end 6 .
Oil at a relatively high input temperature, typically from 175 to 182° C. is fed in at or adjacent to the upstream end 4 and oil at a relatively low temperature of from 150 to 155° C. is continuously removed from the fryer 2 at the downstream end 6 . An outlet 8 at the downstream end 6 connects to a first side 9 of a first heat exchanger 10 which heats the oil. An output line 12 from the first side 9 of the first heat exchanger 10 connects to an inlet 14 at the upstream end 4 of the fryer 2 . This provides a first closed circuit 16 for recirculating the oil for the fryer 2 , the recirculated oil being heated by the first heat exchanger 10 .
On a second side 11 of the first heat exchanger 10 is a second closed circuit 18 for a working fluid. The working fluid undergoes phase changes between a liquid and a gas, and vice versa, within the second closed circuit 18 . Typically, the working fluid may comprise water, a refrigerant, such as an organic refrigerant, or any other suitable working fluid having a boiling point in the desired temperature range as described hereinafter. For example, the working fluid may be carbon dioxide. Typically, the boiling point is less than 125° C., which is a typical input temperature for the steam entering the first heat exchanger 10 for vaporising the working fluid.
In the second closed circuit 18 , there is provided a second heat exchanger 20 and a compressor 22 , typically a mechanical vapour compressor 22 . At an output 24 of the second side 11 of the first heat exchanger 10 , liquid working fluid exits and is fed along a conduit 25 to an input 26 of a first side 28 of the second heat exchanger 20 . The working fluid in liquid form passes through the first side 28 of the second heat exchanger 20 where it is vaporised and an output 30 feeds the vaporised working fluid to the compressor 22 . The compressor 22 compresses the vapour to an elevated temperature and pressure. The working fluid in vapour form at elevated pressure and temperature is then fed along an output conduit 32 from the compressor 22 to an input 34 of the second side 11 of the first heat exchanger 10 .
On a second side 35 of the second heat exchanger 20 is at least one input 36 for a fluid heat source, in the form of steam, and an output 38 for condensate, in the form of water. The fluid heat source undergoes a phase change, from a gas to a liquid, within the second side 35 of the second heat exchanger 20 and the resultant latent heat given up is employed, together with the heat transfer resulting from the elevated input temperature of the fluid heat source, to vaporise the working fluid which passes through the first side 28 of the second heat exchanger 20 . The condensed working fluid on output 38 is received in a condensate collection tank 40 .
As described hereinafter, the steam comes from the fryer vapours and the recovered water condensate from the fryer vapours is collected in the collection tank 40 which can then form a supply of water to be used elsewhere within the manufacturing plant or in the production process, for example for washing potatoes used to form the potato chips to offset or reduce fresh water consumption at the factory. The recovered water may be further cooled to ambient temperature using commercially available cooling equipment.
A hood 44 is disposed above the fryer 4 to capture steam which is generated by the dehydration of the foodstuff, typically potato slices, during the frying process. The lower periphery 46 of the fryer hood 44 covers substantially all of the upper periphery 48 of the fryer 4 so that substantially all of the steam is captured within the fryer hood 44 as it rises from the fryer oil during the frying process. The hood 44 extends at least partially over the conveyor 7 , so that the fried foodstuff product on the conveyor 7 is exposed to the atmosphere within the hood 44 after removal from the oil.
The fryer hood 44 has an exit 50 connected to a conduit 52 . The conduit 52 in turn is connected to the input 36 on the second side 35 of the second heat exchanger 20 . The conduit 52 is substantially vertically oriented to form a vertically oriented fryer hood exhaust stack 54 . A fan 56 , driven for example by an electric motor (not shown), may be disposed within the conduit 52 to exhaust steam upwardly from the hood 44 . A sensor 79 , which may be a pressure sensor or an oxygen sensor, may be provided in the fryer hood 44 or the stack 54 to provide feed forward control of the fan 56 . A particulate filter 57 is located within the conduit 52 above the hood 44 .
At the top of the exhaust stack 54 a first conduit branch 58 connects to a chimney 60 for exhausting a portion of the steam to atmosphere. Alternatively, the steam may be condensed and cooled to ambient temperature using commercially available cooling equipment. The water collected may be directed to the collection tank 40 . A second conduit branch 62 connects to the input 36 . Valves (not shown) may be provided within the first conduit branch 58 and second conduit branch 62 for selectively opening or closing the respective branch 58 , 62 .
Accordingly, steam from the frying process is fed, as a gaseous heat source, to the second heat exchanger 20 . The steam condenses within the second heat exchanger 20 to form a liquid condensate on output 38 which is collected in the tank 40 . Steam accordingly gives up thermal energy which vaporises the working fluid on the other side of the second heat exchanger 20 . The vaporised working fluid is delivered to the compressor 22 which compresses the gaseous working fluid to an even higher temperature and pressure. Such high temperature and pressure working fluid is then fed to the input 34 of the second side 11 of the first heat exchanger 10 which then transfers a large amount of energy to the fryer oil passing through the first side 9 of the first heat exchanger 10 . Typically, the fryer oil is fed from the fryer 2 to the first heat exchanger 10 at an input temperature of about 150 to 155° C. and exits the first heat exchanger 10 at a temperature of about 165 to 180° C. In the second side 11 of the first heat exchanger 10 the working fluid condenses, and the liquid is then conveyed to the second heat exchanger 20 where it is vaporised and the cycle is repeated.
An engine 66 is powered by burning a combustible gas, such as natural gas. Typically, the engine 66 is a gas turbine engine. An electrical generator 72 , for generating an alternating current electrical power output, is connected to the output shaft 68 of the gas engine 66 to generate electricity. The electricity is used to drive the compressor 22 . The compressor 22 carries one or more rotatable compressor discs 70 for compressing the steam flow within the compressor 22 .
In the embodiment, the output electrical power of the electrical generator 72 driven by the gas engine 66 is greater than the electrical power required to drive the compressor 22 . The surplus electrical power output is for use on site or in the factory.
The gas engine 66 has an exhaust 74 for combustion products which is connected as an input 76 to a second side 78 of a third heat exchanger 80 , oil within the first closed circuit 16 for recirculating the oil for the fryer 2 being passed through a first side 82 of the third heat exchanger 80 . An output 84 of the second side 78 of the third heat exchanger 80 connects to the chimney 60 for exhausting the combustion products from the gas engine to atmosphere. The exhaust provides additional heat for heating the fryer oil in the first closed circuit 16 .
Therefore the gas engine 66 is employed not only to provide electrical power to drive the vapour compressor 22 , and optionally to generate surplus electrical power for use on site, but also to provide a high grade energy source to supplement the final proportion of energy required for oil heating, by using the exhaust gas to give up waste heat from the gas engine 66 to the oil.
The exhaust 54 feeds exhaust gas from the gas engine 66 at a typical temperature of about 300 to 500° C. and the output 78 conveys gas at a typical temperature of about 230° C. to the chimney 40 .
This provide a highly energy efficient heating system for the fryer oil which also recovers waste steam to produce useful condensate, and optionally generates electricity.
Typically, the steam exiting the fryer hood 44 upwardly along the conduit 52 and entering the input 56 of the second heat exchanger 20 is at a temperature of from 100 to 150° C., typically about 125° C., and at a pressure at or less than atmospheric pressure.
In the compressor 22 the gaseous working fluid is compressed to an elevated pressure to form a high pressure gas at an elevated temperature. For example, the compressed liquid working fluid exiting the compressor 22 , and therefore fed as a working fluid to the first heat exchanger 10 , is at a temperature of from 190 to 220° C., typically about 190° C., and at a pressure of from 10×10 5 Pa absolute to 15×10 5 Pa absolute.
In the second side 11 of the first heat exchanger 10 , the high pressure gaseous working fluid is condensed to form a liquid, thereby releasing latent heat which is transferred to the oil on the opposite side of the first heat exchanger 10 , thereby heating the oil. Such high temperature and high pressure gaseous working fluid therefore transfers a large amount of thermal energy in the first heat exchanger 10 from the working fluid to the oil on the first side 9 of the first heat exchanger 10 . The cooled liquid working fluid is output from the first heat exchanger 10 and conveyed to the second heat exchanger 20 where the working fluid is vaporised by the input heat from the steam. The cycle is completed by feeding the vaporised fluid to the compressor 22 which forms the high pressure gas which is then conveyed for liquefaction in the first heat exchanger 10 .
Compared to a conventional industrial scale commercial potato chip fryer, the frying method and apparatus of the present invention can yield significant energy and cost savings.
For example, a conventional fryer uses a gas-powered heater to heat the oil exiting the outlet end of the fryer tank and the heated oil is recycled back to the inlet end of the fryer tank. The oil is typically heated from a temperature of about 155° C. to a temperature of 185-190° C. The steam is typically either exhausted to the atmosphere or fed into a thermal oxidiser for destruction of volatile material within the fryer vapours and then exhausted to the atmosphere.
The recovery of steam in accordance with the preferred embodiment not only provides a water source but recovers significant amounts of energy from the steam, both the thermal energy and the latent heat, which are used to heat a working fluid in a second heat exchanger of a closed circuit for the working fluid, which working fluid in turn is used to heat the oil in the first heat exchanger after conversion of the working fluid into a high pressure/high temperature working fluid by the compressor. The compressor is driven by an engine driven by a combustible gas and the exhaust energy is at least partly employed to heat the oil in the third heat exchanger.
The use of the frying method and apparatus of the present invention can achieve fuel savings of approximately 50% or greater as compared to the conventional fryer. In addition, water is recovered which reduces water costs elsewhere in the facility.
Although the present invention has been described with reference to a fryer apparatus, it would be apparent to the skilled person that the apparatus for heating an operating fluid, using a closed circuit, may be employed in a variety of other industrial apparatus and processes where waste heat is employed to provide energy to a fluid using a closed circuit incorporating the phase change of a working fluid, with a vapour compressor being employed to compress a vapour to provide a high grade heat source for heating the operating fluid.
Other modifications to the present invention will be apparent to those skilled in the art and are encompassed within the scope of the present invention. | An apparatus for heating an operating fluid, the apparatus comprising a closed circuit for a working fluid, the closed circuit having first and second heat exchangers and a compressor therebetween, the first heat exchanger having a heat input side for connection to an external fluid heat source and a heat output side for vaporizing working fluid within the closed circuit, the compressor being a vapor compressor adapted to compress the vaporized gaseous working fluid from the first heat exchanger to form a higher pressure gaseous working fluid, and the second heat exchanger having a heat input side for receiving and condensing the higher pressure gaseous working fluid from the compressor and a heat output side for heating an external operating fluid. A corresponding method is also disclosed. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to domestic refrigerators and more particularly to an air circulation system for a refrigerator cabinet.
Conventional frostless-type refrigerators utilize forced refrigerated air flow to cool fresh food and freezer compartments. An electric fan draws refrigerated air across an evaporator coil with most of the air being forced into the freezer compartment and then returned to the evaporator. Some of the refrigerated air is delivered to the fresh food compartment through an air inlet opening therein. An adjustable damper is sometimes provided in the air inlet opening to adjust the amount of air directed into the refrigeration compartment to effect a greater or lesser amount of cooling.
Traditionally the control system for a top mount freezer/refrigerator consists of a separate control for each of the freezer and fresh food compartments. The control for the fresh food compartment is a sensing device (thermostat) located in the fresh food compartment which reacts to the supply air directed across it. The freezer section is governed by the relationship between the thermostat and the ratio of air directed into the freezer compartment. The ratio can be varied by an adjustable baffle which is located in the communicating duct between the freezer and fresh food compartments. By changing the baffle position, the air ratio between the two compartments is varied with a net result being that the freezer temperature is modified. However, the freezer temperature is also modified if the set point of the thermostat governing the fresh food compartment is changed. When the thermostat position is changed, the times required to fulfill the cooling needs of the fresh food compartment are modified, resulting in either a reduction or increase in the cooling system on/off time. Since the thermostat is the control for the cooling system, the fresh food compartment will be satisfied and the freezer section will only cool to a temperature governed by the air ratio and the cooling system run time.
U.S. Pat. No. 4,614,092 discloses an air baffle located in the refrigerator compartment which can be adjusted for varying the air flow into the refrigerator compartment.
U.S. Pat. No. 4,920,765 discloses a rotatable valve for controlling the amount of cooled air flowing from the freezer to the refrigerator compartment.
SUMMARY OF THE INVENTION
The present invention is directed to an air flow and control system for a refrigerator which is built with a "double-tub" plastic liner. The "double-tub" design means that two separate liners for the refrigerator compartment and freezer compartment are formed separately and are inserted into a metal outer wrapper prior to the introduction of an insulating foam between the compartments and the metal wrapper. The two compartments are also separated by a layer of insulating foam.
The present invention utilizes a single control which is similar to a dual control in that it uses a thermostat to control the fresh food compartment and the freezer section is controlled by an air flow ratio between the two compartments. The difference is that on a single control the air ratio is preset before the product leaves the factory and is non-consumer adjustable. In order to modify the freezer compartment temperature, a change to the thermostat position is required. However, when the thermostat position is changed it will also effect a temperature change in the fresh food compartment. Since the freezer cannot be independently controlled, the temperature profile, if graphed, follows a straight angled line.
Because the product only has one consumer accessible control, involvement required from the consumer is limited. This is a benefit in that the consumer has a readily accessible control in the thermostat which will control both compartments. The single control eliminates the need for the consumer to try and decipher how the unit is to be set up for proper operation.
In the event that a consumer requires a freezer temperature which is not obtainable with the preset ratio and thermostat control, it will be possible to modify the temperature line in the field. The duct which will communicate between the fresh food and freezer compartments will have a non-consumer adjustable baffle in it. If a change is required, a service technician can modify the air flow ratio by linearly moving the baffle into one a plurality of different positions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of a top mount refrigerator/freezer embodying the principles of the present invention with the doors open.
FIG. 2 is a side sectional view of the refrigerator/freezer of FIG. 1 with the doors removed.
FIG. 3 is an exploded view of portions of the freezer compartment and air flow system.
FIG. 4 is a side sectional view through the air tower.
FIG. 5 is a partial side sectional view of the air tower rear wall.
FIG. 6 is a partial front sectional view of the air tower with a baffle in the factory preset position.
FIG. 7 is a partial front sectional view of the air tower with the air baffle moved to a more restricting position.
FIG. 8 is a perspective view of an alternate embodiment of an adjustable baffle.
FIG. 9 is a partial elevational view of the baffle of FIG. 8.
FIG. 10 is a graphic representation of energy intercepts comparing single control versus dual control air flow systems.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIGS. 1 and 2 there is illustrated a top mount refrigerator/freezer appliance generally at 20 which includes a freezer compartment 22 on or above a refrigerator or fresh food compartment 24. The freezer compartment is defined by a liner 26 and the fresh food compartment is defined by a liner 28. These liners are placed within an outer metal shell 30 and the intervening space between the shell 30 and the liners 26, 28 is filled with an insulating foam 32. The insulating foam also extends in a space 34 between the freezer liner 26 and the fresh food liner 28.
Cooling within the compartments 22, 24 occurs through the provision of a refrigerant supplied to an evaporator 36 from a compressor 38. Air is directed by a fan (not shown) to flow over the evaporator 36 to cool the air which is then directed into the freezer compartment 22 and refrigerator compartment 24. The air from the evaporator 36 is discharged into an air tower 40 where the air flow is split into two streams, one stream flowing into the freezer compartment through apertures 42 in the air tower and the other stream being directed down to the fresh food compartment through a duct 44 in the air tower. Temperature within the refrigerator compartment is controlled by an adjustable thermostat (not shown) which can be user adjustable through use of a control knob 46.
One or more return air ducts 52 pass through the insulated space 34 between the freezer liner 26 and fresh food compartment liner 28 and exit through openings 54 in the freezer compartment liner 26. These openings 54 are positioned in a channel 56 positioned below a bottom plate 58 in the freezer compartment 22 and the channels communicate with a space behind the evaporator cover 48 to allow for a commingling of the return air from the freezer compartment 22 and fresh food compartment 24 in the cooling space occupied by the evaporator 36 located behind evaporator cover 48. All of the chilled air which has flown across the evaporator 36 exits from the space through an opening 58 in the evaporator cover 48 to flow into the air tower 40.
The air tower 40 is comprised of a front member 60 and a rear member 62. The front member 60 comprises a substantially solid front wall 64, a solid top wall 66 and side walls 68. Near a top of the side wall 68 are the openings 42 through which chilled air is directed into the freezer compartment 22. The rear member 62 comprises a solid wall which encloses the back side of the front member 60 and which forms the air conduit 44 in the lower portion of the tower 40.
In the preferred embodiment illustrated in FIGS. 4-7, the front member has a pair of fixed internal baffles 70, 72 (FIGS. 6, 7) which direct air to flow through a gap 74 between the two baffles into the conduit 44 leading toward the fresh food compartment 24. A third baffle 76 is carried on the rear member 62 and it defines a second gap 78 through which the air must flow to the conduit 44. The position of the third baffle 76 relative to the first and second baffles 70, 72 is determined by means of a detent means in the form of a key 80 which is formed on the front member 60 and which extends into a slot 82 formed in the rear member 62.
As seen best in FIG. 5, a single slot 82 is formed in the rear member 62 so that the third baffle 76 will be factory preset in a specific spacing relative to the first and second baffles 70, 72. Two additional partial slots 84, 86 are provided above and below the through slot 82. A service technician can remove the thin web 88, 90 covering one of the partial slots 84, 86 so that the position of the rear member 62 can be vertically shifted relative to the front member in a linear manner, thereby changing the size of the gap 78 between the second baffle 72 and the third baffle 76. By shifting the rear member 62 down, the gap 78 will be made larger thus resulting in a higher ratio of air flow being directed into the refrigerator compartment 24 and thus a smaller temperature differential between the refrigerator compartment and the freezer compartment. By shifting the rear member 62 upwardly, the gap will be made smaller, thereby reducing the ratio of air flow to the refrigerator compartment and increasing the temperature differential between the refrigerator compartment and the freezer compartment.
The air which has passed through the second gap 78 continues through the conduit 44 and into an air diffuser 92 which is held in place by a snap cap 94. The air diffuser 92 and cap 94 have a front opening 96 and a rear opening 98 to allow air to be diffused into the fresh food compartment 24.
An alternate embodiment of an air tower is shown at 40a in FIGS. 8 and 9. In most respects, the construction of a front member 60a is the same as that described above, with the exception being the area of the internal baffles. In the alternate embodiment, a single baffle 100 is provided which has a fixed portion 102 and a linearly slidingly movable portion 104. A detent arrangement 106 is provided between the fixed baffle 102 and the movable baffle 104 to permit the movable baffle to be selectively placed in one of a plurality of specific positions. The movable baffle 104 will define a gap 106 between the end of the movable baffle and a side wall 68a of the front member 60a. In this embodiment, the rear member would merely be the evaporator cover 48.
As above, as the movable baffle 104 has its position changed, the temperature differential between the freezer compartment and the fresh food compartment will be changed.
FIG. 10 is a graphic representation of the comparison of the freezer compartment temperature noted along the vertical axis with the fresh food compartment temperature noted along the horizontal axis. Dashed line 120 represents the temperatures achieved by using the single control arrangement of the present invention wherein the adjustable thermostat is used to select the temperature for the fresh food compartment. Since the air ratio is preset, the temperature profile is represented by a straight angled line. Thus, if the user operated the thermostat to achieve a temperature of 40° F. within the fresh food compartment, a temperature of approximately -2° F. would be achieved in the freezer compartment. Similarly, a selection of 45° F. in the fresh food compartment would result in a temperature of 5° F. in the freezer compartment. If the user determined that this temperature differential was too small and therefore the freezer temperature too warm, the service technician could adjust the baffle within the air tower to achieve a greater differential resulting in a colder freezer temperature as represented by the dash and dot line 122. Thus, when the fresh food compartment is set at 45° F. the temperature in the freezer compartment would be approximately 4° F. and when the temperature in the fresh food compartment is lowered to 40° F., the increased ratio would cause an even greater differential and the freezer compartment temperature would be lowered to less than -5° F.
Conversely, if the temperature differential were desired to be lowered (warmer freezer) the service technician could make the appropriate adjustment to the baffles to achieve the dashed and dot line profile represented by line 124.
Solid line 126 represents a temperature profile which could be achieved with a dual control refrigerator freezer. Typically mandated energy reporting procedures relating to energy consumption require that these refrigeration units be tested with controls set at their midpoints and then, depending on the resulting operating conditions, the controls are set to either the warm/warm or cold/cold settings. Energy is then reported at the intersection of either 5° F. freezer or 45° F. fresh food compartment temperatures, after interpolating between the two points. The advantage of a single control is that it is possible to report minimum energy consumption without comprising temperature performance at other control settings.
Ideally minimum energy consumption would occur at the point 5° F. and 45° F. However, if the air ratio is modified to allow a dual control to intersect at this point, the performance at the midpoint would be poor. Since the single control varies the freezer temperature and fresh food temperature at the same time, it is possible to intersect at this point without affecting the performance of the unit at its thermostat mid position.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of our contribution to the art. | An air circulation system in a two compartment refrigeration device is provided wherein a restriction device in the form of movable baffles is located in an air conduit connecting the two compartments. The baffles are held in a factory pre-set position by a detent arrangement and the baffles can be selectively moved relative to one another in a non rotatable fashion, such as linearly by service personnel in order to change the ratio of air flowing into the two compartments. | 5 |
RELATED APPLICATIONS
This application claims priority, under 35 U.S.C. § 120 as a continuation-in-part, to P.C.T. international application Serial No. PCT/US03/23633 filed Jul. 29, 2003 and designating the United States, which is a continuation of U.S. patent application Ser. No. 10/306,263 filed Nov. 27, 2002 now abandoned. By this reference the full disclosures, including the drawings, of P.C.T international application Serial No. PCT/US03/23633 and U.S. patent application Ser. No. 10/306,263 are incorporated herein as though now set forth in their respective entireties. Additionally, the full disclosure, including the drawings, of Applicant's co-pending U.S. patent application entitled VIBRATING TRANSDUCER WITH PROVISION FOR EASILY DIFFERNTIATED MULTIPLE TACTILE STIMULATIONS filed May 26, 2005 in the name of David M. Tumey is incorporated herein as though now set forth in its entirety.
FIELD OF THE INVENTION
The present invention relates to music technology. More particularly, the invention relates to a metronome with provision for communication with a musician through tactile stimulation and being particularly adapted for the generation and communication of complex rhythmic patterns and measure timing, e.g., the timing of downbeats, in addition to being adapted to the communication of variable tempos.
BACKGROUND OF THE INVENTION
The metronome is well established as a fundamental tool of musical education. Having been developed before the advent of the electrical apparatus, the traditional metronome comprises a mechanical assembly adapted to generate a clicking sound at a desired beat frequency. With the advent of modern electronics a very precise audio output may now be produced or, as is particularly useful for the musical education of deaf persons, the output signal from the metronome may be communicated with a visual indicator such as a flashing light.
While the improvements made possible through technology are meritorious, Applicant has discovered that the improvements generally serve only to better implement a fundamentally flawed method. In particular, Applicant has noted that the audio nature of the metronome, which is apparently a holdover from the days of primitive technology, is distracting to the musician and, in at least some musical environments, ineffective due to the inability of the musician to clearly hear the audio signal. Additionally, the audio signal is wholly inappropriate for use by the hearing impaired. While this latter issue has been at least addressed through metronomes with visual outputs, it is noted that the use of the visual indicator mandates that the musician completely memorizes his or her music.
It is therefore an overriding object of the present invention to improve over the prior art by providing a metronome that is free of the foregoing flaws. In particular, it is an object of the present invention to provide a metronome having a tactile output such that the musician may feel the desired beat regardless of the volume of the performance or a particular user's physical limitations. Additionally, it is an object of the present invention to provide such a metronome that also may be programmed to provide enhanced capabilities such as, for example, complex output rhythms and/or tactile stimulation designed for the development of articulation. Finally, it is an object of the present invention to provide such a metronome that is also economical to produce and easy to use.
SUMMARY OF THE INVENTION
In accordance with the foregoing objects, the present invention—a tactile metronome for use by a musician—generally comprises a signal generator for producing an electrical signal according to a desired timing scheme and a tactile transducer in electrical communication with the signal generator. The tactile transducer, which may comprise a piezoelectric device, a buzzer, electrodes, a bone density resonator, an electrical stimulation device, a mechanical transducer, an eccentric motion generator or any substantial equivalent, is adapted to impart a tactile sensation to the musician in response to the generated electrical signal. A strap, which may comprise an elastic material or a soft cloth material with hook and loop fasteners, is preferably provided to secure the tactile transducer in place on the musician's body.
In at least one embodiment, the signal generator is adapted to produce complex rhythms and may be programmable such that the musician may define the complex rhythm. In this embodiment, the signal generator preferably further comprises a micro-controller.
In at least one embodiment of the present invention, a vibrating transducer for producing multiple, readily differentiable tactile stimulations is provided. In the preferred embodiment of the present invention, the vibrating transducer generally comprises a rigid housing; an electric motor enclosed within the rigid housing and having attached thereto an eccentric weight; and wherein the electric motor is supported within the rigid housing by a flexible motor mount. The rigid housing comprises a generally cylindrically shaped tube.
The flexible motor mount may be formed of a cushion, which may be made from foam material or the like. In at least one embodiment of the present invention, the cushion is wrapped substantially about the electric motor, centering the electric motor within the cylindrically shaped tube forming the rigid housing. In order to facilitate manufacture of the vibrating transducer of the present invention, the cushion may be wrapped by a securing sheet such as, for example, a thin paper wrapping, a length of adhesive tape or the like.
In a further embodiment of the vibrating transducer of the present invention, a driver circuit may be provided for facilitating operation of the electric motor. The driver circuit may include a current amplifier.
A display, such as a liquid crystal display or a light emitting diode display, is provided to facilitate selection of the desired output frequency or rhythmic pattern. Likewise, a user interface is provided for input of rhythmic patterns, operational control and the like.
Finally, many other features, objects and advantages of the present invention will be apparent to those of ordinary skill in the relevant arts, especially in light of the foregoing discussions and the following drawings, exemplary detailed description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Although the scope of the present invention is much broader than any particular embodiment, a detailed description of the preferred embodiment follows together with illustrative figures, wherein like reference numerals refer to like components, and wherein:
FIG. 1 shows, in a perspective view, one embodiment of the tactile metronome of the present invention as operably employed by a musician;
FIG. 2 shows, in a functional block diagram, the preferred embodiment of the tactile metronome of the present invention;
FIG. 3 shows, in an exploded perspective view, the preferred embodiment of a vibrating transducer as has been found to be optimum for use with the tactile metronome of FIG. 2 ;
FIG. 4 shows, in a cross sectional side view, details of the arrangement of the internal components of the vibrating transducer of FIG. 3 ;
FIG. 5 shows, in a cross sectional end view taken through cut line 5 - 5 of FIG. 4 , additional details of the arrangement of the internal components of the vibrating transducer of FIG. 3 ;
FIG. 6 shows, in a partially cut away perspective view, a representation of the forces produced in the operation of the vibrating transducer of FIG. 3 ;
FIGS. 7A through 7F show, in schematic representations generally corresponding to the view of FIG. 5 , changes in the relative positions of various internal components of the vibrating transducer of FIG. 3 , which changes occur as a result of the operational forces represented in FIG. 6 ;
FIG. 8 shows, in a schematic diagram, details of one embodiment of a driver circuit, as depicted in FIG. 2 , appropriate for operation of the vibrating transducer of FIG. 3 ;
FIG. 9 shows, in a voltage waveform aligned with a musical score, a representative signal as may be generated by the signal generator of FIG. 2 for operation through the driver circuit of FIG. 2 of the vibrating transducer of FIG. 3 , the waveform having characteristics such that the tempo and timing of measures of the score of FIG. 9 may be readily perceived by a musician employing the tactile metronome of the present invention in a manner such as depicted in FIG. 1 ; and
FIG. 10 shows, in a voltage waveform aligned with a musical score, a representative signal as may be generated by the signal generator of FIG. 2 for operation through the driver circuit of FIG. 2 of the vibrating transducer of FIG. 3 , the waveform having characteristics such that the tempo and timing of measures, as well as the rhythm, of the score of FIG. 10 may be readily perceived by a musician employing the tactile metronome of the present invention in a manner such as depicted in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Although those of ordinary skill in the art will readily recognize many alternative embodiments, especially in light of the illustrations provided herein, this detailed description is exemplary of the preferred embodiment of the present invention, the scope of which is limited only by the claims appended hereto.
Referring now to the FIGS. 1 and 2 , the tactile metronome 20 of the present invention is shown to generally comprise a signal source 41 in electrical communication with a contact device 21 comprising, at minimum, a tactile transducer 23 and which, as will be better understood further herein, is adapted to impart to a user 48 a tactile stimulation. As particularly shown in FIG. 2 , the signal source 41 preferably comprises a signal generator 42 , for generating an electrical signal for delivery to the tactile transducer 23 , the generated electrical signal having electrical characteristics indicative of user selected measure (or downbeat) timing, tempo and rhythmic pattern, and a controller 47 for facilitating user selection of the characteristics of the signal generated by the signal generator 42 . A display, which may comprise a liquid crystal display, light emitting diode display or any other substantially equivalent structure, and a user input system, which may comprise a touch screen control, computer interface such as a USB port, wireless interface or the like, or buttons or dials, are also preferably provided in connection with the controller 47 for use inputting and monitoring user selections.
As particularly shown in FIG. 1 , the contact device 21 , which is preferably adapted for wear on the user's ankle, wrist, chest, spinal region or other appropriate location, generally comprises a strap 22 of soft cloth and/or elastic material having a tactile transducer 23 affixed to an interior side thereof. The strap 22 may comprise releasably engageable hook and loop type fasteners, such as are commercially available under the well-known trademark “VELCRO,” or any other substantially equivalent fastener system, for snuggly securing the strap 22 about the user's ankle, wrist, chest, spinal region or other location. In this manner, those of ordinary skill in the art will appreciate that the strap 22 is adapted to facilitate intimate contact between the tactile transducer 23 , which may comprise a piezoelectric device, buzzer, pair of electrodes, a bone density resonator, an electrical stimulation device, a mechanical transducer, an eccentric motion generator or any other substantially equivalent structure capable of imparting the desired tactile stimulation, and the user's body. Additionally, an electrical cable or power cord 30 , which preferably terminates in a standard plug 31 , enabling the signal source 41 of the present invention to be utilized with any of a variety of tactile transducers 23 , provides electrical communication between the contact device 21 and an output jack from the signal source 41 .
In use, as particularly shown in FIG. 1 , a musician 48 affixes the tactile transducer 23 in a minimally obtrusive location utilizing the strap 22 . The musician 48 then connects the electrical cable 30 between the contact device 21 and the signal source 41 by inserting the standard plug 31 into the output jack of the signal source 41 . An output power level selector 45 is preferably provided, as described in more detail further herein, to adjust the “feel” of the tactile metronome 20 of the present invention.
With the tactile transducer 23 positioned as desired, the musician 48 utilizes the provided control input and display to set the beats per minute and, if desired, rhythmic pattern, to be generated by the signal generator 42 . To this end, those of ordinary skill in the art will recognize that the display should be adapted to provide a digital readout of the current setting. Additionally, however, it is contemplated by the present invention that the display may also be adapted to provide a graphical readout comprising a musical score, such as those shown in the upper portions of FIGS. 9 and 10 , especially when the controller 47 is programmed to produce more complicated rhythms such as that depicted in FIG. 10 . In any case, with the tactile metronome 20 of the present invention in proper position and set up as desired, the musician 48 may perform his or her musical instrument of choice while literally feeling the desired beat and without having to divert attention to listen to a traditional metronome or watch for flashing lights or the like.
As will be appreciated by those of ordinary skill in the art, especially in light of this exemplary description, the controller 47 may be readily provided with a timing circuit or programmed to provide complex beat patterns. In such an embodiment, a communication interface or other programming input as well as read only or non-volatile random access memory are preferably provided for the signal source 41 such that the musician 48 may input and/or select a desired beat pattern. In one such embodiment, as will be discussed in further detail herein, an electronic score may be programmed into the controller, either directly or through a computer or PDA interface, whereafter the user need only select desired tempo and starting point to have the tactile metronome 20 of the present invention produce rhythmic stimulation for literally a complete musical selection.
Referring now to the FIGS. 3 through 7 in particular, a preferred embodiment of the tactile transducer 23 is shown to comprise a vibrating transducer 24 having the unique ability to produce multiple easily differentiated tactile stimulations. As shown in the figures, such a vibrating transducer 24 generally comprises an electric motor 28 having attached thereto an eccentric weight 33 and encased within a rigid housing 25 . As is typical with pager transducers and the like, operation of the electric motor 28 turns a shaft 34 upon which the eccentric weight 33 is mounted with, for example, a pin 35 . As will be appreciated by those of ordinary skill in the art, rotation upon the shaft 34 of the eccentric weight 33 produces a vibratory effect upon the motor 28 resulting from the forward portion 32 of the motor 28 attempting to shift laterally outward from the nominal axis 36 of rotation of the shaft 34 , as depicted by the centrifugal force lines F in FIG. 6 .
In typical implementations of this principle, the electric motor is rigidly fixed to some body such as, for example, a pager or cellular telephone housing with mounting clamps, brackets or the like. In the present implementation, however, unlike the vibrating transducers of the prior art, the electric motor 28 is encased within a rigid housing 25 by the provision of a flexible motor mount 37 , which allows the forward portion 32 of the electric motor 28 to generally wobble within the rigid housing 25 as the eccentric weight 33 is rotated upon the motor shaft 34 . In this manner, the resultant forces F are the product of much greater momentum in the eccentric weight 33 than that obtained in the fixed configuration of the prior art.
In the preferred implementation, as particularly detailed in FIGS. 3 through 6 , the flexible motor mount 37 generally comprises a wrapping of preferably foam cushion material 38 , which is sized and shaped to snuggly fill the space provided between the electric motor 28 and the interior of the rigid housing 25 . To facilitate manufacture of the vibrating transducer 24 , as generally depicted in FIG. 3 , the foam cushion 38 may be held in place about the body of the electric motor 28 with a cushion securing sheet 40 , which may comprise a thin paper glued in place about the cushion 38 , thin adhesive tape or any substantially equivalent means. To complete the manufacture of the vibrating transducer 24 , the cushioned electric motor 28 , with eccentric weight 33 attached to its shaft 34 , is inserted into the rigid housing 25 and secured in place by the application of epoxy 27 into the open, rear portion 26 of the housing 25 . As will be understood by those of ordinary skill in the art, the epoxy 27 also serves to stabilize the power cord 30 to the electric motor 28 , thereby preventing accidental disengagement of the power cord 30 from the electric motor 28 .
Referring now to FIGS. 5 through 7 in particular, the enhanced operation of the vibrating transducer 24 is detailed. At the outset, however, it is noted that in order to obtain maximum vibratory effect, the rigid housing 25 is provided in a generally cylindrical shape, as will be better understood further herein. In any case, as shown in the cross sectional view of FIG. 5 , and corresponding views of FIGS. 7A through 7F , the forward portion 32 of the electric motor 28 is encompassed by the forward portion 39 of the foam cushion 38 . At rest, i.e. without the electric motor 28 in operation, the electric motor 28 is substantially uniformly surrounded by the foam cushion 38 , as shown in FIG. 7A .
Upon actuation of the electric motor 28 , however, the centrifugal forces F generated by the outward throw of the eccentric weight 33 causes the axis of rotation 36 of the motor's shaft 34 to follow a conical pattern, as depicted in FIG. 6 . As a result, the forward portion 32 of the electric motor 28 is thrown into the forward portion 39 of the foam cushion 38 , depressing the area of cushion adjacent the eccentric weight 33 and allowing expansion of the portion of the cushion generally opposite, as depicted in FIGS. 7B through 7F corresponding to various rotational positions of the eccentric weight 33 .
As is evident through reference to FIGS. 7B through 7F , the cooperative arrangement of the cushion 38 about the electric motor 28 , as also enhanced by the cylindrical shape of the rigid housing 25 , allows the eccentric weight 33 to build greater momentum than possible in embodiments where the motor is rigidly affixed to a body. As the forward portion 39 of the foam cushion 38 compresses under the centrifugal forces F of the eccentric weight 33 , however, a point is reached where the foam cushion 38 is no longer compressible against the interior wall of the rigid housing 25 and the forward portion 32 of the electric motor 28 is repelled away from the interior wall toward the opposite portion of interior wall.
The result is a vibratory effect much more pronounced than that obtained in prior art configurations calling for the rigid affixation of an electric motor to a housing. Additionally, Applicant has found that the resulting pronounced vibratory effect is generally more perceptible to the human sense of touch than is that produced by prior art configurations. In particular, small differences on the order of tens of milliseconds or less in duration of operation of the vibrating transducer 20 , i.e. duration of powering of the electric motor 28 , are easily perceived and differentiated. As a result, this implementation of the vibrating transducer 24 is particularly adapted for implementation of the tactile metronome 20 of the present invention, which preferably comprises provision for distinct tactile stimuli representing downbeats versus divisional beats as well as the generation and communication of complex rhythms, which may require very quickly perceived stimulations with very little pause therebetween.
As previously discussed, the signal source 41 of the tactile metronome 20 of present invention preferably comprises a driver circuit 43 for interfacing with the tactile transducer 23 . In particular, as shown in FIG. 8 , such a driver circuit 43 preferably comprises an output amplifier 44 , which will generally be required for any implementation in which logical level signals will be expected to drive an electric motor such as is utilized in the preferred implementation of vibrating transducer 24 . As will be appreciated by those of ordinary skill in the art, this requirement stems from the fact that such an electric motor 28 will generally have a current requirement beyond the capabilities of most solid state components. Additionally, in such implementations, the driver circuit 43 will also require implementation of a power conditioning circuit 46 , as also shown in FIG. 8 , having the capability to prevent and/or suppress voltage spiking, such as may be expected in response to the highly inductive load typical of the type of electric motor 28 utilized in the implementation of the vibrating transducer 24 .
As shown in FIG. 8 , an exemplary output amplifier 44 , as is appropriate for use with the foregoing described vibrating transducer 24 , comprises a 2N3904 NPN BJT transistor Q 1 , configured as an emitter follower, coupled with a TIP 42 high current PNP transistor Q 2 in a TO- 220 heat dissipating package, for providing the necessary current for operation of the electric motor 28 of the vibrating transducer 24 . As will be recognized by those of ordinary skill in the art, the output amplifier 44 as shown may be considered a two stage, high current emitter follower. The power conditioning circuit 46 , which is preferably provided to prevent and/or suppress voltage spiking, such as may be expected in response to the highly inductive load typical of the type of electric motor 28 utilized in the implementation of the vibrating transducer 24 may be implemented by tying a 10 μF electrolytic capacitor C 1 ground from the 9-V power bus from, for example, a 9-V battery BAT. As will be recognized by those of ordinary skill in the art, the electrolytic capacitor C 1 will temporarily supply additional current to the 9-V bus as may be required to compensate for transients resulting from the draw upon the output amplifier 44 caused during startup of the electric motor 28 of the vibrating transducer 24 . Additionally, the power conditioning circuit 46 preferably comprises an ON-OFF switch SW 1 and may also include a power on indicator, if desired.
In order to adjust the “feel” of the tactile metronome 20 of the present invention, as previously discussed, the output from the output amplifier 44 is preferably fed through an output power level selector 45 to an output jack J 2 , into which the power cord plug 31 of the power cord 30 to the electric motor 28 of the vibrating transducer 24 may be operably inserted. As shown in FIG. 8 , the output power level selector 45 preferably comprises a 22 Ω resistor R 2 , which is selectively placed in series with the output circuit by selecting the appropriate position of a single pole, single throw switch SW 2 . Although Applicant has found that 22 Ω is an appropriate value for the resistor R 2 , it is noted that the value is selected empirically in order to obtain the user desired tactile feel for the “low” output selection. Additionally, those of ordinary skill in the art will recognize that the resistor R 2 may be replaced with a potentiometer, thereby providing a fully adjustable output power level.
Although the driver circuit 43 has been described as being integral with the signal source 41 , it should be appreciated that the present invention contemplates that any necessary driver circuit 43 may be provided as part of the tactile transducer 23 . In this manner, the signal source 41 may be utilized with virtually any type of tactile transducer 23 , the driver circuit 43 being adapted to provide all necessary electrical compatibility between the chosen tactile transducer 23 and the signal source 41 . In such an implementation, the driver circuit 43 should be provided with an input jack J 1 for receiving signals from the signal generator 42 .
In any case, as previously discussed, the tactile metronome 20 of the present invention is preferably adapted to impart to a musician 48 tactile stimulations indicative of tempo and measure timing, as shown in FIG. 9 , as well as of tempo, measure timing and complex rhythmic patterns, as shown in FIG. 10 . In particular, the preferred embodiment of the present invention contemplates imparting tempo information by the timing of the beginning of signal outputs from the signal generator 42 . In order to differentiate downbeats, indicative of measure timing, the signal generator 42 is adapted under the control of the controller 47 to produce a signal output of longer duration than those indicative of divisional beats, the former of which will be noticeably perceived by the musician 48 as being of much greater intensity than the latter, especially when imparted through the foregoing described vibrating transducer 24 . As shown in FIG. 9 , the controller 47 is programmed to implement these aspects of the present invention by simply effecting at a set tempo a repeating pattern of output pulses from the signal generator 42 representing the downbeats and divisional beats.
As shown in FIG. 10 , however, the tactile metronome 20 of the present invention is also preferably adapted to impart to a musician 48 tactile stimulations indicative of not only tempo and measure timing, but also complex rhythmic patterns. In this case, the controller 47 is preferably programmed to “follow” the score of a user chosen musical selection. In the alternative, however, the controller 47 may be pre-programmed with a plurality of rhythmic patterns, which may be simply selected through user input to the controller 47 . As will be appreciated by those of ordinary skill in the art, the latter will have great utility in mastering basic rhythms. In any case, the preferred embodiment of the present invention contemplates that an appropriate programming interface be provided to allow the user to input to the controller 47 any desired rhythmic pattern or, for that matter, an entire musical score. As shown in FIG. 10 , the controller 47 controls the signal generator 42 to produce output pulses only when the score calls for a note to be performed, giving greater duration, or intensity, to those pulses corresponding to downbeats.
While the foregoing description is exemplary of the preferred embodiment of the present invention, those of ordinary skill in the relevant arts will recognize the many variations, alterations, modifications, substitutions and the like as are readily possible, especially in light of this description, the accompanying drawings and claims drawn thereto. In any case, because the scope of the present invention is much broader than any particular embodiment, the foregoing detailed description should not be construed as a limitation of the scope of the present invention, which is limited only by the claims appended hereto. | A tactile metronome for use by a musician generally includes a signal generator for producing an electrical signal according to a desired timing scheme and a tactile transducer in electrical communication with the signal generator. The tactile transducer, which may take the form of a piezoelectric device, a buzzer, electrodes or any substantial equivalent, is adapted to impart a tactile sensation to the musician in response to the generated electrical signal. A strap, which may be formed from an elastic material or a soft cloth material with hook and loop fasteners, is provided to secure the tactile transducer in place on the musician's body. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of U.S. Pat. No. 8,566,907 (U.S. application Ser. No. 13/594,342, filed Aug. 24, 2012), which is a Continuation of U.S. Pat. No. 8,272,032 (U.S. application Ser. No. 10/985,334, filed on Nov. 10, 2004) the contents of which are hereby incorporated by reference in their entireties into the present disclosure.
FIELD OF THE INVENTION
[0002] The present invention is related generally to the prevention of fraudulent use of online services. More specifically, the present invention relates to a method of controlling access to a network service.
BACKGROUND OF THE INVENTION
[0003] The Internet is a wide area network that connects hundreds of thousands of computers and smaller sub-networks world-wide. Businesses, government bodies and entities, educational organizations, and individuals publish information or data organized in the form of websites. A website may comprise multiple web pages that display a specific set of information and may contain links to other web pages with related or additional information. Some web pages include multiple web pages that are displayed together in a single user interface window. Each web page is identified by a Uniform Resource Locator (URL) that includes the location or Web address of the computer that contains the resource to be accessed in addition to the location of the resource on that computer.
[0004] While web pages offer a host of information and services, not every service provider can offer web pages to which the public has unrestricted access. Online banking, subscription services, online medical records, online academic records, e-mail accounts, select government web sites, and confidential company web pages are just a few examples of areas where access by the general public to a network service generally is restricted. One way to facilitate restricted access is for service providers to require that individuals attempting to access a restricted website use a login identification (ID) procedure that generally includes a username and a password.
[0005] Additionally, some websites require membership including a paid subscription to access various services. Members are provided with identification information to allow access to the website and the subscription feature. A problem associated with this procedure is the fraudulent use of account information by the approved user. For example, a user may have a valid login ID and password to a subscription service for which the user pays a fee. The user may distribute their valid login information to others such that multiple users have access to the service while only one subscription fee has been paid. This fraudulent access to a network service is not remedied by anti-hacker methods of security.
[0006] Multiple login by unapproved users can cause many problems for service providers, other approved users of the service, and even for the approved user that distributes their account information. Service providers lose money if the fraudulently entered service is a subscription service for which only one fee is paid. If the website is, for example, a secure business website, the business may lose the confidentiality of valuable or extremely sensitive information. Additionally, congestion and/or overload of a provider's server may occur if more users than the server can handle are simultaneously accessing the service. For example, a provider may have 1,000 users with valid accounts who are permitted access to a network service. Knowing the number of valid users, the service provider may ensure that if 1,000 users are simultaneously accessing the service there will be no overload, slow service, or other server related problems. However, if due to fraudulent distribution of access information the number of users exceeds 1,000, provision of the service may become slow or even unavailable. Such disruption injures the providers reputation and interferes with the service access of valid users.
[0007] Access to the service by unapproved users may also have adverse effects for the user that fraudulently distributes the login information. Users may not be fully cognizant of the fact that other individuals possessing the user's login information may have access not only to the service, but to personal information. If the service is a subscription service payable by credit card, an individual with the user's login information may be able to view and to change the credit card information. Individuals with the user's account information may also be able to make account changes and incur additional fees to the user's account. Users may not realize these potential pitfalls when they provide others with their account information.
[0008] Prior systems have restricted access to the network service by identifying if a user is already accessing the service and disallowing a second access. Thus, prior systems do not allow multiple access to a network service from a single user account. However, a user may access a service, for example, from a work computer and later in the same day access the service from a home computer without logging out of the service before leaving work. Prior systems that control access to a network service do not allow the user multiple access to the service causing significant inconvenience to the user. Thus, there is a need for a system that discourages the fraudulent distribution of account access information for a network service while allowing a valid user access to a service from multiple locations.
SUMMARY OF THE INVENTION
[0009] An embodiment of the invention relates to a method of controlling multiple access to a network service to prevent fraudulent use of the network service. The method includes, but is not limited to, identifying an account access counter for an account using identification information received from a user at a first device using a network, comparing the account access counter to a maximum account access number, and providing the user at the first device access to a service at a second device if the account access counter is less than the maximum account access number. The user is requesting access to the service provided at the second device. The account access counter is the number of service access sessions active for the account. The maximum account access number defines a maximum number of service access sessions allowed for the account.
[0010] Another embodiment of the invention relates to one or more computer-readable media having computer-readable instructions stored thereon that, upon execution by a processor, cause the processor to control multiple access to a network service to prevent fraudulent use of the network service. The instructions are configured to identify an account access counter for an account using identification information received from a user at a first device using a network, to compare the account access counter to a maximum account access number, and to provide the user at the first device access to a service at a second device if the account access counter is less than the maximum account access number. The user is requesting access to the service provided at the second device. The account access counter is the number of service access sessions active for the account. The maximum account access number defines a maximum number of service access sessions allowed for the account.
[0011] Another embodiment of the invention relates to a system device for controlling multiple access to a network service to prevent fraudulent use of the network service. The system device comprises a control access application, a communication interface, a memory, and a processor. The control access application includes, but is not limited to, computer code configured to identify an account access counter for an account using identification information received from a user at a first device using a network, to compare the account access counter to a maximum account access number, and to provide the user at the first device access to a service at a second device if the account access counter is less than the maximum account access number. The user is requesting access to the service provided at the second device. The account access counter is the number of service access sessions active for the account. The maximum account access number defines a maximum number of service access sessions allowed for the account. The communication interface is configured to receive the identification information from the first device. The memory is configured to store the control access application. The processor is coupled to the memory and to the communication interface and is configured to execute the control access application.
[0012] Yet another embodiment of the invention relates to a system for controlling multiple access to a network service to prevent fraudulent use of the network service. The system comprises a first device in communication with a second device using a network. The first device includes, but is not limited to, a control access application, a first communication interface, a first memory, and a first processor. The control access application includes, but is not limited to, computer code configured to identify an account access counter for an account using identification information received from a user at a second device using a network, to compare the account access counter to a maximum account access number, and to provide the user at the second device access to a service if the account access counter is less than the maximum account access number. The user is requesting access to the service. The account access counter is the number of service access sessions active for the account. The maximum account access number defines a maximum number of service access sessions allowed for the account. The first communication interface is configured to receive the identification information from the second device. The first memory is configured to store the control access application. The first processor is coupled to the first memory and to the first communication interface and is configured to execute the control access application.
[0013] The second device includes, but is not limited to, a second application, a second communication interface, a second memory, and a second processor. The second application includes, but is not limited to, computer code configured to prompt the user for the identification information and to present the service to the user. The second communication interface is configured to send the identification information to the first device and to receive information relating to the service from the first device. The second memory is configured to store the second application. The second processor is coupled to the second memory and to the second communication interface and is configured to execute the second application.
[0014] Yet another embodiment of the invention relates to a method of controlling multiple access to a network service to prevent fraudulent use of the network service. The method includes, but is not limited to, sending identification information from a first device to a second device using a network and receiving the service at the first device if the account access counter is less than a maximum account access number. The identification information identifies an account for a service. The account has an account access counter that is the number of service access sessions active for the account. The maximum account access number defines a maximum number of service access sessions allowed for the account.
[0015] Other principal features and advantages of the invention will become apparent to those skilled in the art upon review of the following drawings, the detailed description, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The preferred embodiments will hereafter be described with reference to the accompanying drawings, wherein like numerals will denote like elements.
[0017] FIG. 1 is a diagram of a system in accordance with an example embodiment of the present invention.
[0018] FIG. 2 is a flow chart illustration of a user validation procedure in accordance with an example embodiment of the present invention.
[0019] FIG. 3 is a flow chart illustration of an identification cookie placement procedure in accordance with an example embodiment of the present invention.
[0020] FIG. 4 is a flow chart illustration of an access procedure for determining accessibility in accordance with an example embodiment of the present invention.
[0021] FIG. 5 is a diagram of an access state table in accordance with an example embodiment of the present invention.
[0022] FIG. 6 is a block diagram of a client device for use in the system of FIG. 1 in accordance with an example embodiment of the present invention.
[0023] FIG. 7 is a block diagram of a server device for use in the system of FIG. 1 in accordance with an example embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] Embodiments of the current invention allow a service provider to control access to multiple users attempting to access a service with identification information associated with a single account. Prior systems determine if the user attempting to access the service is already accessing the service. If the user is already accessing the service, the user is not allowed access to the service a second time. However, a user may access a service, for example, from a work computer and later in the same day from a home computer without logging out of the service before leaving work. Prior systems that control access to a service do not allow the user to access the service multiple times. As a result, the user may not be allowed access to the service at home. The account may be a banking account to which the user needs immediate access. The user then would be required to return to work to exit the service before being allowed to access the account again.
[0025] The present invention provides control of the access to a service through a single account while also allowing the user to have multiple simultaneous active service access sessions. In one embodiment, the user is assigned a maximum account access number. The maximum account access number defines a maximum number of service access sessions allowed for the account. A validation procedure is executed to ensure that the user is not exceeding the maximum account access number with the current access attempt. Thus, the user may be allowed to access the service from both a work computer and a home computer without logging out from the service. In addition, an identification cookie placement procedure may be used as a convenience to the user. The identification cookie placement procedure allows a user to access a service multiple times from the same device without affecting the maximum account access number if the access attempts are made within a predetermined access time period after the identification cookie is placed on the user's computer. The access time period represents a time interval during which the user is allowed access to the service from the user's computer.
[0026] FIG. 1 is a diagram of a system in accordance with an example embodiment. The system 250 is comprised of multiple devices that can communicate through a network. For example, as shown with reference to FIG. 1 , the system 250 includes a first device 280 that accesses a service provided at a second device 270 through the Internet 290 . To access the service provided by the second device 270 , a user at the first device 280 sends identification information to identify the account associated with use of the service. The second device 270 monitors the number of active service access sessions currently provided through the account to determine if the user at the first device 280 is provided access to the service.
[0027] The system 250 may comprise any combination of wired or wireless networks including, but not limited to, a cellular telephone network, a wireless Local Area Network (LAN), a Bluetooth personal area network, an Ethernet LAN, a token ring LAN, a wide area network, the Internet 290 , etc. The system 250 may include both wired and wireless devices. For exemplification, the system 250 shown in FIG. 1 includes the Internet 290 . Connectivity to the Internet 290 may include, but is not limited to, long range wireless connections, short range wireless connections, and various wired connections including, but not limited to, telephone lines, cable lines, power lines, digital cable, etc. The system 250 shown in FIG. 1 in an exemplary embodiment includes a desktop computer 270 and a notebook computer 280 . The devices may include computers of any form factor, a Messaging Device (MD), a Personal Digital Assistant (PDA), and/or a cellular telephone. The system 250 may include additional devices and devices of different types as well as any combination of these devices.
[0028] FIG. 2 shows a flow chart illustrating a validation procedure that identifies the account that the user is attempting to access. A user begins the process by accessing a login web page 10 presented at the first device 280 and provided by a web server at the second device 270 . In an operation 20 , the user enters identification information that may include a user ID and a password. First time users may be required to provide personal information and to select the user ID and/or the password before being allowed to continue. The user submits the identification information to the service provider in an operation 30 . A test is implemented in an operation 40 to determine if the identification information authenticates the user. For example, if the submitted user identification information matches the information stored in a database for a known valid user of the service, the user is authenticated. If not, the user is redirected back to the login web page 10 or to an error page and may try to log in again. If the user is successfully authenticated, the user is provided access to the service provided at the second device 270 .
[0029] Upon successful completion of the validation procedure of FIG. 2 , an ID cookie placement procedure is implemented in an exemplary embodiment. FIG. 3 shows a flow chart illustrating the ID cookie placement procedure in accordance with an example embodiment. The purpose of the procedure is to allow a user direct access to the service if the user has accessed the service from the same device within a predetermined access time period after the identification cookie is placed on the first device 280 . An ID cookie contains the identification information for the account and is placed on the first device 280 when the user successfully accesses the service. A user ID number may be associated with the identification information in a database accessible from the second device 270 . The user ID number allows the service provider to identify each of its users with a single parameter. Thus, when information relative to the account is needed, the user ID number is used to query for data associated with the account. In an exemplary embodiment, the ID cookie remains valid for a time period determined by the service provider. When the predetermined access time period expires, the cookie deletes itself from the first device 280 .
[0030] With reference to FIG. 3 , in an operation 50 , the user ID number is selected from a database at the second device 270 using the identification information sent from the first device 280 . Thus, the identification information is associated with the user ID number. In an operation 60 , a test determines if a valid ID cookie is located at the first device 280 . If a valid ID cookie exists, a user has accessed the service provided at the second device 270 from the first device 280 within the access time period defined by the service provider. The user ID number associated with the ID cookie is identified from the ID cookie in an operation 70 if the ID cookie exists. In an operation 80 , a test determines if the user ID number selected from the database in operation 50 matches the user ID number identified from the ID cookie in operation 70 . Thus, the comparison 80 determines whether the user currently attempting to access the service is the same as the user that last accessed the service from the first device 280 .
[0031] If the comparison 80 indicates that the user ID numbers are the same, the user is granted access to the service in an operation 90 . This process ensures that a user can log in multiple times from the same computer with the same account without having to worry about exceeding a maximum account access number. If the comparison 80 indicates that the user ID numbers are different, the ID cookie on the first device 280 is invalidated in an operation 110 . In an alternative embodiment, operation 110 may not be implemented to allow multiple cookies to reside on the first device 280 so that users with different accounts may use the same device to access the service.
[0032] If the ID cookie on the computer is invalidated in an operation 110 or it is determined in operation 60 that an ID cookie does not exist on the first device 280 , an access procedure is executed in an operation 130 as discussed further with reference to FIG. 4 . If the stored validation procedure 130 returns a success, a new ID cookie is created and stored on the first device 280 in an operation 120 . The ID cookie contains the user ID number selected from the database using the identification information. After placement of the ID cookie on the first device 280 , the user is granted access to the service in an operation 90 . The ID cookie, in an exemplary embodiment, deletes itself after the access time period expires causing execution of the access procedure in the operation 130 . Thus, the access time period represents a time interval during which the user is allowed access to the service at the first device without execution of the access procedure to determine if the user is allowed access to the service. If the stored validation procedure 130 returns a failure, the user is directed to an error page in an operation 140 and access to the service is denied.
[0033] The access procedure 130 determines whether the current access attempt exceeds the maximum account access number allowed for a user through a single account. In one embodiment, when a user successfully logs in to a service, an entry is created for the user in an access state table. The access state table entry contains, for example, the user ID number and an account access time designating the time at which the user successfully accessed the service provided at the second device 270 . When a user subsequently attempts to access the service, the access state table is searched for the user ID number. If the user ID number is found, a determination of whether a user continues to access the service is performed. If the user continues to access the service, an account access counter is compared to the maximum account access number to determine whether the access procedure returns a success or a failure.
[0034] FIG. 4 is a flow chart illustrating the access procedure of operation 130 in detail in an exemplary embodiment. In an operation 150 , an executive table is searched to determine if the access procedure should return a success regardless of the number of active access sessions through the account. An executive table may contain a list of user ID numbers of individuals who are not subject to access restriction. For example, such users may include, but are not limited to, employees of the service provider, users who pay a higher fee for executive status, or complementary account holders. If a user ID number is found in the executive table in the operation 150 , the access procedure returns a success in an operation 160 . If the user ID number is not found in the executive table in the operation 150 , a timeout value and the maximum account access number are read from a configuration table in an operation 170 . The timeout value represents a time interval during which access to the account is controlled. The timeout value and the maximum account access number may be defined in the configuration table as single values applied to all user accounts. In an alternative embodiment, the configuration table may be searched by checking the table for an entry corresponding to the user ID number that is associated with the identification information provided by the user during the authentication procedure. Thus, in this embodiment, each account may have a different timeout value and the maximum account access number. In yet another alternative embodiment, different account levels may be defined that allow a different timeout value and a different maximum account access number for each account level.
[0035] The configuration table may contain information about other limitations on a user's account. The maximum account access number is the maximum number of service access sessions allowed for the account. For example, if the maximum account access number is two, the user may access the service from two different devices, but not a third, possibly until the timeout period defined by the timeout value expires.
[0036] The access state table is searched in an operation 180 using the user ID number that has been determined from the identification information. Each account is thereby associated with a unique user ID number. An exemplary embodiment of an access state table is shown with reference to FIG. 5 . The access state table 440 includes, but is not limited to, a user ID number 442 , an account access time 444 , and an account access counter 446 for each entry 450 , 452 , 454 , 456 . The account access time 444 is the time that the account is accessed by the user. The account access time 444 may include the date in addition to a time. For example, the account access time 448 associated with user ID number 06774592 includes the date Oct. 26, 2004 as 2004:10:26 and the time 1:38:14 pm as 13:38:14. Alternatively, the date may be included in a separate field. In another alternative embodiment, the date may not be included in the access state table 440 . The account access counter 446 is the number of service access sessions active for the account. The access state table 440 may contain a list of all users and the information concerning the user's last access to the service. Alternatively, the access state table 440 may contain a list of user ID numbers 442 corresponding to users who have recently accessed the service. The table entries may be removed from the access state table when the user exits the service or may be removed on a periodic basis to reduce the size of the access state table 440 . In an exemplary embodiment, the access state table maintains a single entry for each user ID number and thus account. If another user is allowed access to the service using the same identification information, the account access time 444 of the user ID number associated with the identification information may be updated with the current time.
[0037] If the user ID number is not in the access state table 440 , the user does not have any active service access sessions. A new session is created and a new entry placed in the access state table 440 in an operation 190 . The new entry is associated with the user ID number. The account access counter 446 is assigned a value of one. The account access time 444 is assigned a value of the current time. Upon entry in the access state table 440 , the access procedure returns a success in the operation 160 . In an alternative embodiment, the access state table 440 may be searched before user account limitations are obtained from the configuration table in operation 170 .
[0038] If the user ID number is found in the access state table 440 in the operation 180 , a test may be performed to determine if the session listed in the table remains active. An active session is a session that is still valid based on the rules defined in the configuration table (i.e. a two hour timeout value means that a user accessing the service again after one hour has an active session). In an operation 200 , this test is performed by comparing the current time to the account access time 444 obtained from the access state table 440 in the operation 180 and the timeout value obtained from the configuration table in the operation 170 . If the current time exceeds the sum of the account access time and the timeout value, the session listed in the access state table is no longer active. In this case, the entry in the access state table corresponding to the user ID number is set, in an operation 210 , such that the account access counter is assigned a value of one and the account access time is assigned a value of the current time. Thus, the account access counter and the account access time are reset. As a result, the access to the service through the account is controlled during the timeout value selected by the service provider.
[0039] If the current time does not exceed the sum of the account access time and the timeout value, the prior login session is still active. In this case, the account access counter 446 obtained from the access state table in the operation 180 is compared, in an operation 220 , to the maximum account access number obtained from the configuration table in operation 170 . If the account access counter 446 is not less than the maximum account access number, the access procedure returns a failure in an operation 245 . If the account access counter 446 is less than the maximum account access number, the account access counter 446 is incremented in an operation 230 . The incremented account access counter is stored in the access state table in an operation 240 . Thus, the existing account access counter for the user ID number is updated with the incremented value. The account access time 444 may additionally be updated with the current time in an alternative embodiment. The access procedure returns a success in the operation 160 .
[0040] For exemplification, FIG. 6 shows a block diagram of an example first device 280 that may be included in the system 250 . The device 305 includes a display 300 , a communication interface 340 , an input interface 310 , a memory 330 , a processor 320 , and a browser application 350 . The device 305 may or may not be mobile. Also, different and additional components may be incorporated into the device 305 . The device 305 , for example, allows a user to connect to a network, such as the Internet 290 , and to view and/or to hear media data using a variety of formats. The components of the device 305 may each be internal or external to the device 305 . The components may connect to each other using a number of different methods as known to those skilled in the art. Connections between the components of device 305 may be other than or in addition to those shown in FIG. 6 .
[0041] The display 300 presents information to the user of the device 305 including, but not limited to, information from the browser application 350 . The display may be, but is not limited to, a thin film transistor (TFT) display, a light emitting diode (LED) display, a Liquid Crystal Display (LCD), a Cathode Ray Tube (CRT) display, etc.
[0042] The communication interface 340 provides an interface for receiving and transmitting calls, messages, and/or any other information communicated across a network including, but not limited to, streaming media and multimedia messages. Communications between the device 305 and the network may be through one or more of the following connection methods, without limitation: an infrared communications link, a wireless communications link, a cellular network link, a physical serial connection, a physical parallel connection, a link established according to the Transmission Control Protocol/Internet Protocol (TCP/IP), etc. Communications between the device 305 and the network may use one or more of the following communication protocols, without limitation: HTTP: HTTP, TCP/IP, real time streaming protocol (RTSP), real time protocol (RTP), user datagram protocol (UDP), multicast UDP, etc. Transferring content to and from the device 305 may use one or more of these connection methods and communication protocols or any others known to those skilled in the art or to be developed in the future.
[0043] The input interface 310 provides an interface for receiving information from the user for entry into the device 305 . The input interface 310 may use various input technologies including, but not limited to, a keyboard, a pen and touch screen, a mouse, a track ball, a touch screen, a keypad, one or more buttons, etc. to allow the user to enter information into the device 305 or to make selections from the device 305 . The input interface 310 may provide both an input and an output interface. For example, a touch screen display allows the user to make selections and presents information to the user.
[0044] The memory 330 provides an electronic holding place for an operating system of the device 305 , the browser application 350 , and/or other applications. The device 305 may have a plurality of memory devices 330 that use the same or different memory technologies. Example memory technologies include, but are not limited to, Random Access Memory (RAM), Read Only Memory (ROM), flash memory, etc. A variety of different storage media may be used for each memory technology. For example, a Compact Disk (CD), a Digital Video Disk (DVD), and a hard disk are all ROM storage media types.
[0045] The processor 320 executes instructions that cause the device 305 to perform various functions. The instructions may be written using one or more programming languages, scripting languages, assembly languages, etc. Additionally, the instructions may be carried out by a special purpose computer, logic circuits, or hardware circuits. Thus, the processor 320 may be implemented in hardware, firmware, software, or any combination of these methods. The term “execution” refers to the process of running an application or program or the carrying out of the operation called for by an instruction. The processor 320 executes an application, meaning that it performs the operations called for by that application in the form of a series of instructions. The processor 320 may retrieve an application from a non-volatile memory that is generally some form of ROM or flash memory and may copy the instructions in an executable form to a temporary memory that is generally some form of RAM. The processor 320 , for example, may execute instructions embodied in the browser application 350 . The device 305 may include one or more processor 320 .
[0046] The browser application 350 may communicate with one or more web server. The browser application 350 may respond to HTTP commands, may interpret hyper text markup language and other Internet programming languages including, but not limited to, Java™ and Perl, and may present a web page for viewing by the user. The browser application 350 may display or otherwise process media data or media streams or provide access to other services through a network accessed through the communication interface 310 .
[0047] For exemplification, FIG. 7 shows a block diagram of a device 365 that includes a display 360 , a communication interface 410 , an input interface 380 , a memory 400 , a processor 390 , an access control application 420 , and a database 370 . Different and additional components may be incorporated into the device 365 . The device 365 communicates website service information to the device 305 . The components of device 365 may each be internal or external to the device 365 . The components may connect using a number of different methods as known to those skilled in the art. Connections may be other than or in addition to those shown in FIG. 7 .
[0048] The display 360 presents information to the user of the device 365 including, but not limited to, information from the access control application 420 . The display may be, but is not limited to, a TFT display, an LED display, an LCD, a CRT display, etc. The display 360 is optional.
[0049] The communication interface 410 provides an interface for receiving and transmitting calls, messages, and/or any other information communicated across a network including streaming media and multimedia messages. Communications between the device 365 and the network may be through one or more of the following connection methods, without limitation: an infrared communications link, a wireless communications link, a cellular network link, a physical serial connection, a physical parallel connection, a link established according to the TCP/IP Standards, etc. Communications between the device 365 and the network may use one or more of the following communication protocols, without limitation: HTTP, TCP/IP, RTSP, RTP, UDP, multicast UDP, etc. Transferring content to and from the device 365 may use one or more of these connection methods and communication protocols or any others known to those skilled in the art or to be developed in the future.
[0050] The input interface 380 may provide an interface for receiving information from the user for entry into the device 365 . The input interface 380 may use various input technologies including, but not limited to, a keyboard, a pen and touch screen, a mouse, a track ball, a touch screen, a keypad, one or more buttons, etc. to allow the user to enter information into the server device 365 or to make selections from the server device 365 . The input interface 380 may provide both an input and an output interface. The input interface 380 is optional.
[0051] The memory 400 provides an electronic holding place for an operating system of the device 365 , the access control application 420 , the database 370 , and/or other applications so that the information can be reached quickly by the processor 390 . The device 365 may have a plurality of memory devices 400 that may use different memory technologies including, but not limited to, RAM, ROM, flash memory, etc.
[0052] The processor 390 executes instructions that cause the device 365 to perform various functions. The instructions may be written using one or more programming languages, scripting languages, assembly languages, etc. Additionally, the instructions may be carried out by a special purpose computer, logic circuits, or hardware circuits. Thus, the processor 390 may be implemented in hardware, firmware, software, or any combination of these methods. The processor 390 executes an application meaning that it performs the operations called for by that application in the form of a series of instructions. The processor 390 may retrieve an application from a non-volatile memory that is generally some form of ROM or flash memory and may copy the instructions in an executable form to a temporary memory that is generally some form of RAM. The processor 390 may execute instructions embodied in the access control application 420 . The device 365 may include one or more processor 390 .
[0053] The access control application 420 provides the functions discussed with reference to FIG. 3 and FIG. 4 . The access control application 420 may interface with a web server application to control access to services provided by the web server application. The access control application 420 is comprised of instructions interpretable by the processor 390 as known to those skilled in the art. In an exemplary embodiment, the access control application 420 is implemented using the Java programming language and Structured Query Language scripts to extract information from the database 370 and to determine the user access to the services provided by the web server application. The web server application responds to HTTP commands and may transmit one or more web page to the device 305 based on the user selection at the device 305 . The access control application 420 may be implemented on the same or a different device from the web server application that provides the service to the user.
[0054] The database 370 may store web pages and information associated with the web pages including media data. The database may utilize various database technologies as known to those skilled in the art including a simple file system and/or a system of tables. The database 370 also may use a variety of different formats as known to those skilled in the art. The device 365 may include a plurality of databases 370 . The database 370 also may be used to store information such as the identification information, the user identification number, the configuration table, and the access state table. The device 365 may include one or more database 370 .
[0055] It is understood that the invention is not confined to the particular embodiments set forth herein as illustrative, but embraces all such modifications, combinations, and permutations as come within the scope of the following claims. The description above focused on a preferred embodiment of the invention designed to control access to multiple users attempting to access a service using the same account information. The present invention, however, is not limited to a particular application. Also, the present invention is not limited to a particular operating environment. Those skilled in the art will recognize that the system and methods of the present invention may be advantageously operated on different platforms using different operating systems including but not limited to the Microsoft® Windows based operating system, Macintosh® operating system, LINUX based operating systems, or UNIX® based operating systems. Additionally, the functionality described may be distributed among modules that differ in number and distribution of functionality from those described herein without deviating from the spirit of the invention. Additionally, the order of execution of the modules may be changed without deviating from the spirit of the invention. Thus, the description of the preferred embodiments is for purposes of illustration and not limitation. | A method is provided for controlling multiple access to a network service to prevent fraudulent use of the network service. The method includes identifying an account access counter for an account using identification information received from a user at a first device using a network, wherein the user is requesting access to a service provided at a second device, and further wherein the account access counter is the number of service access sessions active for the account; comparing the account access counter to a maximum account access number, wherein the maximum account access number defines a maximum number of service access sessions allowed for the account; and providing the user at the first device access to the service at the second device if the account access counter is less than the maximum account access number. | 7 |
FIELD OF THE INVENTION
[0001] The current invention relates to a dynamic system using online tools for determining dynamically the value of any property being non real estate property, more specifically a system capable of determining the equilibrium market price of property based on potential consumer reactions to sale offers.
BACKGROUND OF THE INVENTION
[0002] Owners and investors in property generally need estimated valuations of their properties to determine the ideal price to sell. For example, owners of a portfolio of priceless art, boats, jewelry, or any other good generally sold at market need to constantly evaluate the price of the property. Experts, such as auction systems also need efficient third party evaluation of property to help with sales. Many methods of valuating property exist including reviewing tax and sales records of comparable properties, using previous sales data, or scouring the internet to find the price of comparable property.
[0003] Ultimately, the value of any given piece of property is the value a buyer is willing to pay for the property on any given day. One method of valuating a property automatically involves a seller placing their product or service for sale, auction or lease on an Internet based web-site where a buyer or seller could then request, review and determine a proper price model based upon a mathematical algorithm calculating length of time on the market, number of inquiries and percentages of successful sales transactions based upon mapping the above equations against each other over time. Often, a person will call an agent, investigate as to increases of market in the region or even try to obtain online comparable properties sold recently in the area. Each of these methods are time extensive and costly.
[0004] While these methods provide valuation methods for properties, they do not provide a reliable method of determining a real market valuation for a property without the need of external third party data and input. There is currently no system capable of determining with a great degree of reliability the current value of a property without extensive investigation. A need exists for a system that will allow a user to dynamically determine the real market valuation for a property using simply and available tools.
SUMMARY OF THE INVENTION
[0005] In one example, a dynamic pricing system includes a dynamic pricing unit including a memory and a processor, the processor of the dynamic pricing unit executing a program performing the steps of gathering a plurality of information on a property unit wherein the property is any property but real estate property, gathering a plurality of information on a market where the property unit is sold, generating a first price for the property unit based on the gathered property unit information and market information, generating a second price and a third price based on the first price for the property unit, posting a portion of the plurality of property information and the first price for viewing by potential buyers on a first web site, posting a portion of the plurality of property information and the second price for viewing by potential buyers on a second web site, posting a portion of the plurality of property information and the third price for viewing by potential buyers on a third web site, monitoring each of the first, second and third web sites to determine the level of interest in the property unit at each of the first price, second price and third price, determining a final price based on the interest level of the web posting for the first price, second price and third price; posting a portion of the plurality of property information and the final price for viewing by potential buyers on a final web site.
[0006] In another example, the property unit is collectible property.
[0007] In another example, the property unit is a product.
[0008] In another example, the second price is higher than the first price and third price.
[0009] In another example, the third price is lower than the first price and second price.
[0010] In another example, the final price is a value between the first price and second price.
[0011] In another example, the market information includes pricing information for a plurality of comparable property units having similar characteristics as the property unit.
[0012] In another example, the dynamic pricing unit performs the step of normalizing the pricing information of each of the plurality of comparable property unit based on the property unit information.
[0013] In another example, the dynamic pricing unit performs the step of gathering information relating to users viewing each of the first web page, second web page and third web page.
[0014] In another example, the dynamic pricing unit performs the step of adjusting the final price based on the information relating to users viewing each web site.
[0015] In another example, a dynamic pricing system includes a property analysis unit configured to gather a plurality of information on a property unit wherein the property is any property but real estate property, a market analysis unit configured to gather a plurality of information on a market where the property unit is sold, a property analysis unit configured to generate a first price for the property unit based on the gathered property unit information and market information, generate a second price and a third price based on the first price for the property unit, a property posting unit configured to post a portion of the plurality of property information and the first price for viewing by potential buyers on a first web site, post a portion of the plurality of property information and the second price for viewing by potential buyers on a second web site, post a portion of the plurality of property information and the third price for viewing by potential buyers on a third web site, monitoring each of the first, second and third web sites to determine the level of interest in the property unit at each of the first price, second price and third price, a pricing analysis unit configured to determine a final price based on the interest level of the web posting for the first price, second price and third price, post a portion of the plurality of property information and the final price for viewing by potential buyers on a final web site.
[0016] In another example, the property unit is collectible property.
[0017] In another example, the property unit is a product.
[0018] In another example, the second price is higher than the first price and third price.
[0019] In another example, the third price is lower than the first price and second price.
[0020] In another example, the final price is a value between the first price and second price.
[0021] In another example, the market information includes pricing information for a plurality of comparable property units having similar characteristics as the property unit.
[0022] In another example, the property analysis unit normalizes the pricing information of each of the plurality of comparable property unit based on the property unit information.
[0023] In another example, the property posting unit gathers information relating to users viewing each of the first web page, second web page and third web page.
[0024] In another example, the pricing analysis unit adjusts the final price based on the information relating to users viewing each web site.
BRIEF DESCRIPTION OF THE DRAWING
[0025] Details of the present invention, including non-limiting benefits and advantages, will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings.
[0026] FIG. 1 depicts a block diagram of an dynamic pricing system suitable for use with the methods and systems consistent with the present invention.
[0027] FIG. 2 shows a more detailed depiction of the dynamic pricing unit.
[0028] FIG. 3 shows a more detailed depiction of the computers.
[0029] FIG. 4 depicts an illustrative example of the operation of the dynamic pricing system.
[0030] FIG. 5 depicts an illustrative example of the operation of the pricing analysis unit gathering market information.
[0031] FIG. 6 is an illustrative example of the operation of the property posting unit adjusting the price of the target property based on activity from various web postings of the property.
[0032] FIG. 7 is an illustrative example of a website for the listing of property where the dynamic pricing model can be used according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0033] While various embodiments of the present invention are described herein, it will be apparent to those of skill in the art that many more embodiments and implementations are possible that are within the scope of this invention. Accordingly, the present invention is not to be restricted except in light of the attached claims and their equivalents.
[0034] Described herein is a system for dynamically determining the real market value for a property of product. The system determines an initial price based on information on comparable properties or products, and posts the property or product at different prices via various web pages. The system then gauges interest in the product or property to determine the real market value of the product or property. While the examples below describe the use of the system for real estate, the system can be used to valuate any products such as furniture, consumer products, collectible items or any other item capable of being valued.
[0035] FIG. 1 depicts a block diagram of an dynamic pricing system 100 suitable for use with the methods and systems consistent with the present invention. The dynamic pricing system 100 comprises a plurality of computers 102 , 104 , 106 and 108 connected via a network 110 . The network 108 is of a type that is suitable for connecting the computers for communication, such as a circuit-switched network or a packet switched network. Also, the network 110 may include a number of different networks, such as a local area network, a wide area network such as the Internet, telephone networks including telephone networks with dedicated communication links, connection-less network, and wireless networks. In the illustrative example shown in FIG. 1 , the network 110 is the Internet. Each of the computers 102 , 104 , 106 and 108 shown in FIG. 1 is connected to the network 110 via a suitable communication link, such as a dedicated communication line or a wireless communication link.
[0036] In an illustrative example, computer 102 serves as a dynamic pricing unit that includes a property analysis unit 112 , a market analysis unit 114 , a property posting unit 116 and a pricing analysis unit 118 . The number of computers and the network configuration shown in FIG. 1 are merely an illustrative example. One having skill in the art will appreciate that the dynamic pricing system 100 may include a different number of computers and networks. For example, computer 102 may include the property analysis unit 112 as well as one or more of the market analysis unit 114 and pricing analysis unit 118 . Further, the property posting unit 116 may reside on a different computer than computer 102 .
[0037] FIG. 2 depicts a more detailed depiction of the computer 102 . The computer 102 comprises a central processing unit (CPU) 202 , an input output (I 0 ) unit 204 , a display device 206 communicatively coupled to the IO Unit 204 , a secondary storage device 208 , and a memory 210 . The computer 202 may further comprise standard input devices such as a keyboard, a mouse, a digitizer, or a speech processing means (each not illustrated).
[0038] The computer 102 's memory 210 includes a Graphical User Interface (“GUI”) 212 which is used to gather information from a user via the display device 206 and I/O unit 204 as described herein. The GUI 212 includes any user interface capable of being displayed on a display device 206 including, but not limited to, a web page, a display panel in an executable program, or any other interface capable of being displayed on a computer screen. The GUI 212 may also be stored in the secondary storage unit 208 . In one embodiment consistent with the present invention, the GUI 212 is displayed using commercially available hypertext markup language (“HTML”) viewing software such as, but not limited to, Microsoft Internet Explorer, Google Chrome or any other commercially available HTML viewing software. The secondary storage unit 208 may include an information storage unit 214 . The information storage unit may be a rational database such as, but not including Microsoft's SQL, Oracle or any other database.
[0039] FIG. 3 shows a more detailed depiction of the computers 104 , 106 and 108 . Each computer 104 , 106 and 108 comprises a central processing unit (CPU) 302 , an input output (I/O) unit 304 , a display device 306 communicatively coupled to the IO Unit 304 , a secondary storage device 308 , and a memory 310 . Each computer 104 , 106 and 108 may further comprise standard input devices such as a keyboard, a mouse, a digitizer, or a speech processing means (each not illustrated).
[0040] Each computer 104 , 106 and 108 's memory 310 includes a GUI 312 which is used to gather information from a user via the display device 306 and I/O unit 304 as described herein. The GUI 312 includes any user interface capable of being displayed on a display device 306 including, but not limited to, a web page, a display panel in an executable program, or any other interface capable of being displayed on a computer screen. The GUI 312 may also be stored in the secondary storage unit 208 . In one embodiment consistent with the present invention, the GUI 312 is displayed using commercially available hypertext markup language (“HTML”) viewing software such as, but not limited to, Microsoft Internet Explorer, Google Chrome or any other commercially available HTML viewing software.
[0041] FIG. 4 depicts an illustrative example of the operation of the dynamic pricing system 100 . In step 402 , the property analysis unit 112 gathers information on a specific property (“target property”). The information may be gathered via a web page displayed on a GUI 212 or 312 that requests specific information on the property including the address of the property, number of bedrooms, total number of rooms, mechanical and electrical systems installed on the property, lot size and any other information relating to the property. The property analysis unit 112 may also retrieve information on the property from public records available such as tax records or deed records. The property analysis unit 112 may identify the municipality where the property is located and electronically contact the municipality to request additional information on the property.
[0042] The property analysis unit 112 may analyze and store documents pertaining to the property that are retrieved from external sources. As an illustrative example, the property analysis unit 112 may retrieve an electronic version plat of survey and calculate the dimensions of the lot where the property resides using known document analysis techniques such as Object Character Recognition (“OCR”), line analysis or any other method of extracting data from a document. At a minimum, the property analysis unit will gather the property address, lot size, number of bedrooms, number of bathrooms, total number or rooms, and total square footage of the property. The property analysis unit 112 may gather additional information on the property such as the schools associated with the property address, crime reports for the area surrounding the property or any other additional information on the property.
[0043] In step 404 , the market analysis unit 114 will gather information comparable to the information gathered on the target property for the real estate market where the target property resides. The market analysis unit 114 may gather information on properties in the market having similar characteristics as the target property such as the same lot size, same number of bedrooms or bathrooms, same square footage, or based on any other similar characteristic. The market analysis unit 114 also gathers sale and purchase information on each property including the year and date of the last sale of a property, the amount the property was listed for and the amount the property sold.
[0044] In step 406 , the market analysis unit 114 generates a high value, low value and medium value for the target property based on the property information and the market information. The market analysis unit 114 may compare prior sales of similar properties to the target property to determine the high, medium and low price points. As an illustrative example, the market analysis unit 114 may set the low price as the lowest price sold for a property having the same or similar square footage, number of bedrooms and number of bathrooms. The market analysis unit 114 may also apply adjustment or weighing factors to compensate for differences in the characteristics of the property. As another illustrative example, the market analysis unit 114 may increase a price by a predefined amount based on differences between the target property and a comparable property. In determining the low, medium and high prices, the market analysis unit 114 may require the low, medium and high prices be separated by a minimum amount of money to ensure the properties are separated during searches.
[0045] In step 408 , the property posting unit 116 generates and displays separate web pages for the low, medium and high price for the target property. Each web page includes the same images and description of the property, but lists the property for a different price. The web pages may be listed on the same website or on different websites. In one embodiment, the property posting unit 116 stores a listing of property sales web sites and posts identical listings on each property sales web site. In another embodiment, the property posting unit 116 posts one web page on separate web sites and adjusts the pricing of the property between the high, low and medium price over a predetermined time period.
[0046] In step 410 , the property posting unit 116 monitors user activity for each of the posted web pages. The property posting unit 116 may monitor and store the number of instances a web page is viewed, the number of e-mails sent concerning a posting, demographic information on the users viewing each posting or any other information relating to the users viewing each posting. In step 412 , the property posting unit 116 gathers all information on each posting and analyzes the information relating to each posting. The property posting unit 116 may assign a value to each posting based on the number of times a user viewed each posting, the demographic information on the person viewing each posting, the number of correspondence from users for each posting or any other information related to the posting.
[0047] The value assigned to each posting represents the likelihood that the purchase price of the target property is accurate. The value may be determined based on the both the quantity and quality of the interest shown in the posting. As an illustrative example, a posting that receives a large number of views and associated correspondence will receive a higher value than a property receiving a smaller number of views. The property posting unit 116 may also review the time period during which the properties are viewed. As another illustrative example, a property that is viewed a number of times over an extended period would receive a higher value than a property that is viewed a similar number of times immediately after the property is posted.
[0048] In step 414 , a new price for the target property is generated using the values calculated for each posting. The new price may be the low price, medium price, high price or a value between the high price and low price. As an illustrative example, if the high price and medium price are assigned similar values, the property posting unit 116 may calculate a target price between the medium price and high price. If the low price and high price receive the same or similar value, the target price maybe a value between the low price and the high price.
[0049] In step 416 , the property posting unit 116 posts a new web page for the target property at the target price. In addition, the property posting unit 116 may post additional postings for the property with the value of the property offset by a predetermined value. The property posting unit 116 may analyze the new postings using the same criteria previously discussed.
[0050] FIG. 5 depicts an illustrative example of the operation of the pricing analysis unit 118 gathering market information. In step 502 , the pricing analysis unit 118 performs a search of property sales databases to identify properties having the same or similar characteristics as the target property. As an illustrative example, the pricing analysis unit 118 may search a database listing properties sold or currently for sale in the same geographical area as the target property. The pricing analysis unit 118 may search for properties having the same or similar characteristics as the target property such as properties having the same or similar bedrooms or square footage.
[0051] In step 504 , the pricing analysis unit 118 generates a list of identifying characteristics in the target property. The identifying characteristics may be any defining characteristic of the property such as the number of bedrooms, the total square footage of the property, the number of garages or parking spots, the acreage where the property resides, the number of floors in the property or any other physical attribute of the property. The identifying characteristics may also include information on the community where the property resides, including the ratings of the schools in the area, the crime rate in the area, the average income of the residents of the area or any other information relating to the market where the property resides.
[0052] In step 506 , the pricing analysis unit 118 identifies characteristics in the identified properties that correspond to each of the characteristics in the target property. In step 508 , the pricing analysis unit 118 adjusts the market value of each identified property based on differences between the identified property and the target property. As an illustrative example, the pricing analysis unit 118 may reduce the value of the identified property if the identified property is located on a lot having less acreage than the target property. In determining the amount the value of the identified property is reduced, the pricing analysis unit 118 may retrieve historical information on the approximate value of each characteristic. In the case of a property with less acreage than the target property, the pricing analysis unit 118 may determine the value of additional acreage to the overall value of a property and adjust the value of the identified property based on the historical information. The historical information may be stored in the memory 210 or secondary storage unit 208 of the dynamic pricing unit 102 or may be located external to the dynamic pricing unit 102 .
[0053] In step 510 , the pricing analysis unit 118 determines weighing values for the target property. The weighing values are determined by analyzing historical sales information on the market to determine specific property characteristics that increase or decrease the value of the property that may not be readily ascertainable by the structure of the property alone. As an illustrative example, a property located within walking distance of public transit may increase the value of a property, while a property located proximate to train tracks may reduce the value of the property. To determine the increase or decrease in the value of the target, the pricing analysis unit 118 uses historical data to determine an increase or decrease in the sale of a property based on a listing of predefined characteristics. The listing of predefined characteristics may be generated based on the geographical location of the property, information on users interested in the property after the initial web posting, estimated demographic information of potential buyers or any other information relating to the value of the property that is not readily apparent from just the structural description of the property alone.
[0054] In step 512 , the pricing analysis unit 118 determines the minimum value of the target property based on the pricing of the identified properties. The minimum value may be the lowest adjusted priced of the previously identified properties. In step 514 , the pricing analysis unit 118 applies weighing factors to the minimum value to determine an initial target price for the property. In step 516 , the market analysis unit determines the medium price and high price by adding an incremental value to the target price. The incremental value may be a set predefined value or may be a percentage of the minimum value. As an illustrative example, the medium price may be fixed at $15,000 above the minimum price or 20% above the minimum price.
[0055] FIG. 6 is an illustrative example of the operation of the property posting unit 116 adjusting the price of the target property based on activity from various web postings of the property. In step 602 , the property posting unit 116 posts web pages listing the target property for sale at a low price, a medium price and a high price. The postings may be on the same or different real estate sales web sites, such as realtor.com, Zillow.com or any other real estate sale web site. In step 604 , the property posting unit gathers information relating to each posting including, but not limited to, the number of views per hour, day, week and month, the duration each user spends viewing the web page, the number and content of each request for additional information on the property and any other information pertaining to the web postings.
[0056] In step 606 , the property posting unit 116 gathers information on the user's viewing the web postings including, but not limited to, the income of the user, the user's interest and hobbies, the age and marital status of the user or any other identifying information. The property posting unit 116 gather this information directly or via an external source to provide information on the user. The information may be gathered using known web demographic applications such as Google Analytics. In step 608 , the property posting unit 116 determines the purchasing characteristics of each user based on the gathered demographic information. The purchasing characteristics may include a determination of whether a user's income would qualify them for a mortgage to purchase the target property. The purchasing characteristics may also include an analysis of the types and prices of properties historically purchased by users with the same or similar demographic information. The historical purchasing information may be gathered and stored in the memory 212 of the dynamic pricing unit 102 based on prior activity on the web sites and deals brokered through the dynamic pricing unit 102 .
[0057] In step 610 , the property posting unit 116 determines the interest level of each user. The interest level of a user is determined based on their activity on the web posting including the number of times the user viewed the web posting, the number of correspondence initiated by the user concerning the web posting, and any other activity relating to the user's interaction with the web posting. The interest level of each user is assigned a score based on the user's interaction. The score and demographic information for each user is stored in the information storage unit 214 .
[0058] In step 612 , the property posting unit 116 generates a weighing factor based on the user information and interest level. In determining the weighing factor, the property posting unit 116 assigns a score to each of the demographic characteristics of the user including the income level, age, marital status, geographic location or any other demographic characteristic. Further, the property posting unit 116 may assign a weight to the ability of the user to obtain a mortgage based on their income information. The property posting unit 116 adjusts the weighting of each user based on the level of interest with the users with a higher level of interest having an increased weighted value. The property posting unit 116 then determines an overall weighing factor based on the average of all the user's weighing factors.
[0059] In step 616 , the property posting unit 116 adjusts, via the pricing analysis unit 118 , the target price of the property by applying the weighing factor from the web site. As an illustrative example, the target price may be set to the medium price posted on the web site. The user information may indicate that users with an income level well above the amount required to obtain a mortgage have indicated a strong interest in the property. They pricing analysis unit 118 may apply a weighing factor generated by the property posting unit 116 that increases the target price of the property. In this way, the target price reflects not only the market price but also the demographic information of users showing interest in the target property.
[0060] FIG. 7 shows a possible embodiment of a website relying on the dynamic pricing technology. In this example, the page includes a world map showing active global listing inventory for property. Multiple different statistics associated with sale and listings are also given along with real time activity graphs. In this model, a user may click to scroll down and select a language of use, a currency, a country, a city, a category, a transaction, a size or even a price. The price for example will be determined using the dynamic pricing system described above. As shown, many other types of properties such as residential listings, commercial listings, vacation listings, private listings, new development listings, notes and debt listings, tax liens, and even portfolio listings can be used as property.
[0061] In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular.
[0062] It should be understood that various changes and modifications to the presently preferred embodiments disclosed herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present disclosure and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims. | A dynamic pricing system including a dynamic pricing unit including a memory and a processor, the processor of the dynamic pricing unit executing a program performing the steps of gathering a plurality of information on a unit of property not real estate property, gathering a plurality of information on a market where the unit of property is sold, generating a first price for the unit of property based on the gathered information on the unit of property and market information, generating a second price and a third price based on the first price for the unit of property, posting a portion of the plurality of property information and the first price for viewing by potential buyers on a first web site, posting a portion of the plurality of property information and the second price for viewing by potential buyers on a second web site, posting a portion of the plurality of property information and the third price for viewing by potential buyers on a third web site, monitoring each of the first, second and third web sites to determine the level of interest in the unit of property at each of the first price, second price and third price, determining a final price based on the interest level of the web posting for the first price, second price and third price, posting a portion of the plurality of property information and the final price for viewing by potential buyers on a final web site. | 6 |
This application is a divisional application of Ser. No. 09/386,009, filed Aug. 30, 1999, which is a division of Ser. No. 08/808,142, filed Feb. 28, 1997 now Pat. No. 5,958,996, which is a division of Ser. No. 08/671,427, filed Jun. 27, 1996 now Pat. No. 5,693,928.
FIELD OF THE INVENTION
This invention relates to diffusion barriers on polymeric articles, and to methods of preparing the diffusion barriers. According to the invention disclosed herein, a polymer blend alloy is prepared containing a high surface energy component and a low surface energy component. The article is then subjected to an ozone containing atmosphere in the presence of ultra violet radiation to form the diffusion barrier. The diffusion barrier is formed by the partial oxidation of the low surface energy component that has diffused to the surface. Exemplary low surface energy components are polysilanes, e.g., having —Si—Si— repeating units, exemplified by [—Si(CH 3 ) 2 —] and the like, and polysiloxanes, e.g., having —Si—O— repeating units, exemplified by [—Si(CH 3 ) 2 O—] and the like.
BACKGROUND OF THE INVENTION
For polymer blends, that is, physical mixtures of two or more polymers or copolymers that are not linked by covalent bonds, and that contain one or more components having lower surface energy than the bulk polymer, polymers, or copolymers, segregation of the low surface energy components to the surface can occur. This results in a hydrophobic surface and inhibits the ability to transfer materials (e.g., inks, paints, dyes) to the surface of an article comprising the blend. This segregation also may result in poor interfacial adhesion between applied layers, films, coatings, adhesives, and the like, and underlying articles comprising the blend.
In other cases, for a homogeneous polymer system, inward diffusion of moisture or other chemicals/materials into the bulk may be a problem. This can result in degradation of the properties of the article.
Thus, there exists a need for surface modification of articles fabricated of polymer blends or alloys to prevent segregation and hydrophobicity, and to enhance the wettability and bondability of the surface.
SUMMARY OF THE INVENTION
For polymer blends, the chemical transformation of the segregated material into a diffusion barrier has been achieved according to our invention. This transformation retards further segregation of the low surface energy component(s) to the surface.
In addition, the modified surface can act as a barrier to inward diffusion of moisture or other undesirable materials.
For a single polymer system, doping of the polymer with a component or components having lower surface energy than the bulk, followed by oxidation with ozone in the presence of ultra violet (uv) radiation will result in a diffusion barrier and a more stable surface with respect to reactions with the environment.
The polymeric body is treated with reactive oxygen (ozone) and UV radiation. The apparatus for this technique is quite modest, usually consisting of a UV source, e.g., a low-pressure mercury vapor lamp, and a chamber to house the UV source and the material being treated. The ozone is the photolysis product of oxygen in the presence of a source, as a mercury vapor light source, emitting 184.9 nanometer radiation. Treatment is almost always performed in air at atmospheric pressure to get ozone.
The method of this invention is particularly useful with organosilicon/organic polymer blends. By organosilicons are meant polysilanes and polysiloxanes, where polysilanes are polymers having —Si—Si— repeating units, exemplified by [—Si(CH 3 ) 2 —] and the like, and polysiloxanes are polymers having —Si—O— repeating units, exemplified by [—Si(CH 3 ) 2 O—] and the like. In these systems conversion of organosilicon materials to silicon oxides is a phenomenon that is well documented for exposure to oxygen plasma environments. Oxygen reactive ion etching of silicon-containing polymers results in an initial thickness loss and a gradual slowing of polymer erosion until etching ceases. During etching, it is believed that mobile silicon-containing monomer or polymer diffuses to the polymer surface where it is converted to SiO 2 or a suboxide thereof, and functions as an increasingly effective etching barrier.
According to our invention, UV/ozone treatment of organic polymers having organosilicon additives results in formation of a thin, protective barrier that inhibits diffusion of bulk material to the surface, inhibits diffusion of material from the environment into the bulk, and inhibits environmental contamination of the surface.
This is achieved by doping the bulk polymer or a surface portion thereof with a suitable organosilicon polymer or monomer additive at an appropriate concentration. The doped blend is then subjected to exposure in a UV/ozone environment such that a thin, stable, protective barrier is formed at the surface.
The method of this invention, and the resulting products are particularly useful, for example,
(1) to enhance printability and adhesion of inks to organosilicon containing polymers, for example, encapsulated products with organosilicon-containing encapsulants (e.g., Dexter Hysol 4450);
(2) to enhance the moisture and chemical resistance of polymers, such as encapsulants, in general, by doping with a suitable additive and treating in UV/ozone;
(3) to enhance the moisture and chemical resistance of other polymers used for a variety of applications requiring diffusion barriers and/or stable surface properties.
A further advantage is that unlike barriers produced by deposition processes, the method of the invention is self-patterning, i.e., the material that constitutes the protective barrier is formed only on the organosilicon-bearing material, not deposited on other areas of the substrate. Also, since the barrier formed by this method is, by the nature of the technique, incorporated as part of the organosilicon-bearing material, not as a separate, deposited layer, adhesion of the barrier to the bulk is high. In addition, the barrier, which is silicon dioxide or a suboxide thereof, is optically transparent (in the visible, and into the 185 nanometer ultraviolet and 1140 nanometer infrared bands) and hydrophilic. The method of the invention is also less expensive than conventional means of producing barrier films.
THE FIGURES
The invention may be understood by reference to the FIGURES appended hereto.
FIG. 1 shows the water contact angle on a film of a organosilicon-polymer—polyepoxide polymer blend as a function of surface treatment and storage times.
FIG. 2 shows the x-ray photoelectron spectroscopy pattern of a sample of a organosilicon polymer—polyepoxide polymer blend after UV/ozone surface treatment.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention described herein, for polymer blends, the chemical transformation of the segregated material into a diffusion barrier has been achieved. The method of this invention utilizes a polymer blend or polymer of a high surface energy material, as an organic polymer, and an excess of a low surface energy material, such as a organosilicon containing polymer, exemplified by a silane, such as an alkyl silane, or a siloxane, having the formula R—Si(OCH 3 ) 3 , R—Si(OCH 3 ) 2 CH 3 , or R—Si(OCH 3 )(CH 3 ) 3 , where R is an alkyl or vinyl group. By “high” and “low” surface energy materials are meant miscible materials differeing in critical surface tension, for example by 5 dynes/centimeter and preferable 10 dynes/centimeter or more. The low surface energy material diffuses toward the surface, where it is converted to an oxide, e.g., SiO x , where x is between 1.6 and 2.0. This transformation or oxidation retards further segregation of the low surface energy component(s) to the surface, and provides a modified surface.
In addition, the modified surface can act as a barrier to inward diffusion of moisture or other undesirable materials.
Unlike barriers produced by deposition processes, the method of this invention is self-patterning, i.e., the material that constitutes the protective barrier is formed only on the organosilicon-bearing material, not deposited on other areas of the substrate. Also, since the barrier formed by this method is, by the nature of the technique, incorporated as part of the organosilicon-bearing material, not as a separate, deposited layer, adhesion of the barrier to the bulk is very high. In addition, the barrier is optically transparent (in the visible, and into the 185 nanometer ultraviolet and 1140 nanometer infrared bands) and hydrophilic. This method is also less expensive than conventional means of producing barrier films.
For a single polymer system, doping of the bulk polymer with a component or components having lower surface energy than the bulk, followed by oxidation with ozone in the presence of ultra violet radiation, will result in a diffusion barrier and a more stable surface with respect to reactions with the environment.
The method of this invention utilizes reactive oxygen and UV radiation. The apparatus for this technique is quite modest, usually consisting of a UV source, e.g., a low-pressure mercury vapor lamp, and a chamber to house the UV source and the articles being treated. The ozone comes from the photolysis of oxygen. A low pressure mercury vapor source emits radiation at wavelengths of 184.9 and 253.7 nanometers. Oxygen molecules, O 2 , absorb 184.9 nanometer radiation and dissociate to form atomic oxygen, O. The atomic oxygen, O, reacts with molecular oxygen, O 2 , to form ozone, O 3 . Thus, treatment is almost always performed in air at atmospheric pressure with the mercury vaport light source, although other ozone sources may be utilized. In comparison with plasma systems, UV/ozone surface treatment equipment is relatively inexpensive.
The method of the invention is to be distinguished from oxygen reactive ion etching. Conversion of organo-organosilicon materials, as silanes and siloxanes, to silicon oxides is a phenomenon that is well documented for exposure to oxygen plasma environments, i.e., oxygen reactive ion etching. Oxygen reactive ion etching of silicon-containing polymers results in an initial thickness loss and a gradual slowing of polymer erosion until etching ceases. During etching, it is believed that silicon-containing monomer diffuses to the polymer surface where it is converted to SiO 2 and functions as an increasingly effective etching barrier.
The method of this invention and the articles produced thereby can be prepared from various polymer blends. The preferred polymer blends are characterized by miscibility of the constituents, and an excess of the low surface energy component, where the “high” and “low” surface energy constituents differ in surface tension, preferably by 5 to 10 dynes/centimeter or more. Exemplary silanes include those generally commercially available silanes, such as dimethyl silane, and exemplary siloxanes are those having the formula R—Si(OCH 3 ) 3 , R—Si(OCH 3 ) 2 CH 3 , or R—Si(OCH 3 )(CH 3 ) 3 , where R is an alkyl or vinyl group, and includes methyl, ethyl, propyl, and vinyl siloxanes. Exemplary organic polymers include polyvinyls, polyepoxides, polycarbonates, polyimides, and polyurethanes. Generally, the preferred polysilanes and polysiloxanes have a surface tension below about 25 to 30 dynes per centimeter, and the preferred organic polymers have a surface tension above about 25 to 30 dynes per centimeter. The preferred blends are within the range of miscibility of the constituents and contain anexcess of the low surface energy organosilicon constituent. Especially preferred are polymer blends of polysiloxanes and polyepoxides.
The invention is illustrated by the following example.
EXAMPLE
Samples of a commercially available epoxy-based encapsulant (Dexter Hysol 4450) containing some organosilicon and other inorganic fillers were exposed to UV/ozone, oxygen plasma, and flame treatments for various durations.
As shown in FIG. 1, advancing DI water contact angle on the Dexter Hysol surfaces were reduced from initial average values greater than 100 degrees to a values less than 10 degrees for UV/ozone and plasma treatments, and to less than 30 degrees for the flame treatment. Contact angles were then monitored as a function of aging the time during storage in lab ambient conditions. As the figure shows, the UV/ozone treated surface maintains its high degree of hydrophilic character upon aging, while the plasma and flame-treated surfaces revert back to a more hydrophobic character. High resolution x-ray photoelectron spectroscopy (XPS) in the Si 2p photoemission band suggest that during UV/ozone and plasma treatments of the Dexter Hysol material, O—Si—C bonds in the siloxane, observed prior to treatment, are converted to SiO x , where x is between 1.6 and 2.
This is illustrated in FIG. 2 which shows high resolution XPS spectra in the Si 2p photoemission band for organosilicon samples before treatment (a), after two minutes of O 2 plasma treatment (b), and after 50 minutes of UV/ozone exposure (c). The spectrum of the untreated sample (a) contains contributions from both the silicon containing polymer (low binding energy) and glass filler (higher binding energy). After treatment (b and c), the organosilicon is transformed into a glassy surface (higher binding energy). For this reason, it is believed that the signal in (b) and (c) is the result of transformation and not exposure of underlying glass-filler particles.
XPS examination of surfaces aged for greater than 40 days revealed that the UV/ozone-treated and plasma-treated surfaces retained a strong SiO x contribution, while the flame-treated surfaces at no time exhibited the SiO x character (i.e., at all times maintained a O—Si—C character).
The increase in contact angle following treatment for plasma-treated and flame-treated parts is due primarily to a combination of two phenomena; (1) some diffusion of organosilicon material from the bulk of the encapsulant to the surface, and (2) changes in surface groups, e.g., decrease in carbon-oxygen groups. Both of these factors influence the surface wetting properties. The apparent lack of reversion in contact angle of the UV/ozone-treated encapsulant surface to its original state is indicative of the formation of a thin, more stable protective barrier against diffusion. In addition, the observation that the UV/ozone-treated surface maintains a highly hydrophilic nature indicates that in addition to resisting diffusion, the UV/ozone-treated surface is resistant to contamination from the environment.
Although the exact mechanisms leading to these differences in the surface properties resulting from each of the treatments are unknown at this time, it is believed that the presence of the intense UV exposure and/or the absence of bombardment by kinetically energetic particles in the UV/ozone system may impart such favorable properties. In addition, since material removal is more pronounced in the plasma system, the formation of the protective barrier may be less effective than that produced using UV/ozone treatment.
UV/ozone treatment of organic polymers having low surface energy organosilicon additives results in formation of a thin, protective barrier that inhibits diffusion of bulk material to the surface, inhibits diffusion of material from the environment into the bulk, and inhibits environmental contamination of the surface.
This is achieved by doping the polymer with a suitable organosilicon additive at an appropriate concentration. The doped blend is then subjected to exposure in a UV/ozone environment such that a thin, stable, protective barrier is formed at the surface.
Several ink formulations were tested for adhesion (Tape Tests) on surfaces of the Dexter Hysol 4450 polysiloxane-polyepoxide polymer blend encapsulant treated using a variety of techniques. Ink was applied to the surface of the surface treated samples, and then the ink was tested for adhesion by consumer adhesive tape. Results are given in the tables below.
TABLE I
Results of Example 1 “As Formed” tape tests.
INK
PLASMA
UV-OZONE
CONTROL
DEXTER
PASS
PASS
PASS
DEXTER W/IPA
NA
PASS
PASS
TRA. TECH M2
PASS
NA
NA
TRA. TECH B/GL
PASS
PASS
PASS
MARKEM 4481
PASS
PASS
FAIL
AIS
PASS
PASS
FAIL
NOTE: FAILS ALWAYS OCCURRED ON BOTH SCOTCH AND KAPTON TAPES AND ON LINES GOING BOTH INLINE AND PERPENDICULAR TO THE TAPE LIFT DIRECTION.
The tests above were repeated after five weeks of aging at ambient conditions of approximately 20 degrees C. and 30-70 percent relative humidity,, and the following results were obtained.
TABLE II
Results of Parts in Table I retested after five weeks of aging.
INK
PLASMA
UV-OZONE
CONTROL
DEXTER
PASS
PASS
PASS
DEXTER W/IPA
NA
PASS
PASS
TRA. TECH M2
PASS
NA
NA
TRA. TECH B/GL
PASS
PASS
PASS
MARKEM 4481
PASS
PASS
FAIL
AIS
PASS
PASS
PASS
Comparison with the wettability tests shown in FIG. 1 showed that the UV-ozone treated samples were more stable then the plasma and control samples.
TABLE III
Results of tape test matrix.
INK
PLASMA
UVOZONE
FLAME
OZONE
CONTROL
DEXTER
PASS
PASS
FAIL
FAIL
PASS
T.T. B/GL
PASS
PASS
PASS
FAIL
PASS
MARKEM
PASS
PASS
FAIL
FAIL
FAIL
4481
AIS
PASS
PASS
PASS
FAIL
FAIL
The results shown in Tables I and III are consistent. Furthermore, treatment with flame and ozone-only (no UV exposure) do not improve markability. In fact, in some instances, adhesion becomes worse with these treatments. However, the plasma and uv/ozone treatments consistently show positive results independent of ink type. Also, Table II illustrates that no degradation over time occurs for markability on parts treated using plasma or uv/ozone processes. Table III also shows good results independent of ink chemistry.
Although both UV/ozone and plasma treatments result in improved markability over extended periods of time (i.e., long shelf life with respect to markability), the UV/ozone treatment results in a more stable surface as inferred from contact angle measurement with respect to hydrophilic properties. In this regard see FIG. 1 .
While the invention has been described with respect to certain preferred embodiments and exemplifications, it is not intended to limit the scope of the invention thereby, but solely by the claims appended hereto. | A method of forming a diffusion barrier on an article of a polymer blend of (i) a high surface energy polymer and (ii) a low surface energy polymer. Most commonly the low surface energy polymer is an organosilicon polymer, as a polysilane or a polysiloxane. The surface of the article is exposed to ozone and ultraviolet radiation to form a diffusion barrier. | 2 |
REFERENCE TO RELATED CASES
[0001] This application is a continuation of PCT/US04/14207, filed May 7, 2004, which has a priority date of May 9, 2003 based on U.S. patent application Ser. No. 10/435,620 filed on May 9, 2003, the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The field of the present invention is devices for the delivery or placement of therapeutic or diagnostic agents into a living body.
[0003] Some medical procedures employ the infusion of therapeutic agents into living bodies over periods of time, making a syringe inconvenient and/or inappropriate. Such procedures have been used for the infusion of insulin, for example. In other cases, monitoring of internal body conditions with small sensors or other devices also makes syringes and like devices inappropriate for continuing access to subcutaneous tissue. To provide access in either circumstance, ports have been devised which provide support for a flexible cannula implanted in the body. Ports typically provide a housing which has a mounting side that is held by tape, dressings or direct adhesive against the body. A flexible cannula extends from the housing into the body.
[0004] Ports used for infusion may be employed in combination with a delivery tube extending to the housing of the port and in communication with the cannula as a complete infusion set. The delivery tube of such an infusion set is in communication with the flexible cannula through an infusion fluid chamber in the port to deliver therapeutic agents. Diagnostic agents such as biosensors may be delivered in like manner.
[0005] To place such ports or infusion sets including such ports, insertion sets have been used. An insertion set typically includes the port and necessarily includes a rigid sharp such as a needle which is placed through the flexible cannula for insertion into the body. The needle typically extends through a resilient barrier such as a resealable resilient mass, through a chamber and then axially through the cannula. Once the cannula has been positioned in the body, the port is positioned and the needle can be withdrawn. The resealing of the mass as the needle is withdrawn prevents fluid from leaking from the port while remaining in position at the site. Once the port has been placed with the flexible cannula extending into the body, the agent or agents can be delivered.
[0006] A first type of insertion set includes an infusion set having the port and a delivery tube in communication with the cannula. The insertion set needle accesses the housing through a different path than the delivery tube. The seal is typically bypassed by the delivery tube in this instance. Alternatively, the insertion set is used with a port rather than a complete infusion set. The delivery tube is placed after insertion of the port to complete an infusion set. The same path is used for the insertion needle as part of the insertion set as is used for communicating the tube of the infusion set with the cannula. In this latter case, the delivery tube is associated with a hub which includes a member able to pierce a resealable resilient mass for communication between the delivery tube and the cannula once the insertion set has been disassembled through retraction of the needle.
[0007] Mechanisms referred to as inserters have been devised to rapidly insert the needle and cannula into the body at the site. For the infusion of insulin in particular, diabetics self medicate. Consequently, they, a family member or other care provider places the port for infusion. This can be emotionally and physically difficult when repeated infusions are required over long periods of time. Inserters alleviate this burden somewhat by making the placement of the needle automatic and quick. Further, pressure by the inserter about the targeted site reduces the sensation of pain.
[0008] Inserters typically include a housing with a driver slidable in the housing. The driver includes a socket to receive the insertion set. A spring is operatively placed between the housing and the driver to advance rapidly an insertion set positioned in the socket. A latch then controls the advancement of the driver. One complete system including an infusion port, an insertion set having the infusion port and an insertion needle, and an inserter is illustrated in U.S. Pat. No. 6,293,925.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to a system for the delivery of therapeutic and/or diagnostic agents and components thereof.
[0010] In a first separate aspect of the present invention, an inserter includes a housing assembly, a port driver in the housing assembly and a spring operatively between the housing assembly and port driver controlled by a latch in the housing assembly. The inserter further includes a cannula insertion member which is retained in a socket in one of the housing assembly and the port driver. A port assembly includes a base having a mounting side, a port opening away from the mounting side and a cannula extending from the base. The cannula insertion member is positionable at the port with the port assembly associated with a seat in the port driver. An access hub includes a connector which is positionable at the port with the port assembly separated from the seat.
[0011] In a second separate aspect of the present invention, an inserter includes a housing assembly, a port driver in the housing assembly and a spring operatively between the housing assembly and port driver controlled by a latch in the housing assembly. The inserter further includes a cannula insertion member which is retained in a socket in one of the housing assembly and the port driver. The cannula insertion member has a needle extending through the port assembly with the port assembly at the driver and a needle hub fixed to the needle. The needle hub is slidable in a passageway associated with the housing assembly a distance which is limited by a stop. If the inserter is to be reusable, the socket is preferably split. The housing assembly includes a web from which the split socket depends. Levers on the other side of the web may be forced toward one another to open the socket and release the needle hub.
[0012] In a third separate aspect of the present invention, any of the foregoing aspects are contemplated to be combined to further advantage.
[0013] Therefore, it is a principal object of the present invention to provide a new inserter for a port assembly including a cannula insertion member. Other and further objects and advantages well appear hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a plan view of a port assembly.
[0015] FIG. 2 is a side view of the port assembly of FIG. 1 .
[0016] FIG. 3 is a cross-sectional view of the port assembly of FIG. 1 taken through the axis thereof along line 3 - 3 of FIG. 2 .
[0017] FIG. 4 is a cross-sectional view of the port assembly taken at 90° to the cross-sectional view of FIG. 3 .
[0018] FIG. 5 is a detail view as seen in FIG. 3 .
[0019] FIG. 6 is a perspective view of a resilient barrier.
[0020] FIG. 7 is a cross-sectional view of the resilient barrier.
[0021] FIG. 8 is a perspective view of a second port assembly.
[0022] FIG. 9 is a cross-sectional view of the port assembly of FIG. 8 taken through the axis.
[0023] FIG. 10 is a cross-sectional view of a third port assembly also taken through the axis of the assembly.
[0024] FIG. 11 is a perspective view of a port inserter.
[0025] FIG. 12 is a cross-sectional view of the port inserter of FIG. 11 taken through the axis of the port inserter.
[0026] FIG. 13 is a cross-sectional view of the port inserter of FIG. 12 with the inserter discharged and closed, the view being at 90° to FIG. 12 .
[0027] FIG. 14 is a cross-sectional view of a second port inserter taken through the axis of the inserter.
[0028] FIG. 15 is a plan view of a third port inserter.
[0029] FIG. 16 is a cross-sectional view taken along an axis of the port inserter of FIG. 15 .
[0030] FIG. 17 is a cross-sectional view taken along an axis of the port inserter of FIG. 15 at 90° to the view of FIG. 16 .
[0031] FIG. 18 is a cross-sectional view taken along an axis of a fourth port inserter.
[0032] FIG. 19 is a cross-sectional view taken along an axis of the port inserter of FIG. 18 at 90° to the view of FIG. 18 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] Turning in detail to the drawings, FIGS. 1 through 7 illustrate a first port assembly, generally designated 20 . The port assembly 20 includes a base 22 which is shown to be frustoconical. The base may alternatively be cylindrical. Other shapes, of course, can also be employed. The base includes a mounting side 24 . The mounting side may include adhesive for retention at a site on a living body. The adhesive is preferably nondrying and may or may not include a coated paper cover to be removed prior to use. A port 26 is arranged in the base 22 to be open to the other side of the base from the mounting side 24 . In this embodiment, the port opens into a cavity 28 defined by a cannula mounting element 30 and a retainer element 32 which are sonically welded, press fit or cemented into the main part of the base 22 .
[0034] A cannula 34 extends from the base 22 . In this embodiment, the cannula extends perpendicular to the mounting side 24 . Other angles might be appropriately employed. The cannula mounting element 30 provides a passage 36 into which the cannula 34 is positioned. The cannula 34 has a mounting flange 38 to retain the cannula 34 from being drawn through the passage 36 . The cannula 34 may be retained in the cannula mounting element 30 and a seal formed with the passage 36 through the use of adhesive, sonic welding where the materials are compatible, a press fit, or sealing elements. In the preferred embodiment, the cannula mounting element 30 insures retention of the cannula 34 by ultrasonically swaging the body of the element 30 to draw material from that element 30 over the flange 38 , as best seen in FIG. 5 .
[0035] The port assembly 20 further includes a resilient barrier 42 . The resilient barrier 42 is preferably an elastomer. It is positioned in the cavity 28 and overlies the cannula 34 . The resilient barrier 42 controls fluid communication from the port 26 to the cannula 34 .
[0036] The resilient barrier 42 is illustrated in this embodiment to be a valve. The valve 42 is defined by a circular elastomeric septum 44 . The septum 44 includes a slit 46 therethrough. The slit 46 is cut so that the valve remains closed when in the unstressed state. A frustoconical concavity 48 provides relief for flexure of the septum 44 downwardly to open the slit 46 . As can best be seen in FIG. 6 , the septum 44 includes shaped protrusions 50 to influence the distortion of the septum 44 with pressure from above. The septum 44 further includes circular beads 52 and 54 . These beads provide seals for sealing contact with components on either side of the septum 44 . Thus, the circular bead 54 provides sealing contact with the cannula mounting element 30 about the cannula 34 and also about the concavity 48 . Thus, the resilient barrier 42 controls communication from the port 26 to the cannula 34 through pressure on the upper side thereof.
[0037] An access hub, generally designated 56 , includes a hub 58 . A connector 60 extends from the main body of the hub 58 . A tube 62 extends laterally from the main body of the hub 58 . A fitting 64 is located at the end of the tube 62 for receipt of an infusion tube (not shown). Other fittings may be employed to rigidly engage such tubing or other components. A passage 66 extends through the fitting 64 , the tube 62 and the connector 60 to provide flow communication through the access hub 56 . The tube 62 has a length of reduced outside diameter to receive a tab 68 . The tab 68 is pivotally mounted about the area of reduced cross section of the tube 62 . The tab 68 includes a split hub 70 for forced mounting on the tube 62 . Ribs 72 on the tab 68 provide increased purchase. The tab 68 has a first position as illustrated in FIGS. 1 and 2 . In a second position, the tab may be pivoted to extend more aligned with the longitudinal direction of the connector 60 for easy gripping between thumb and forefinger.
[0038] The access hub 56 is constructed such that the connector 60 can be positioned through the port 26 into the cavity 28 and fully against the resilient barrier 42 , as seen in each of the relevant Figures. The bottom of the connector 60 includes a surface able to press against the shaped protrusions 50 on the opposed surface of the circular elastomeric septum 44 . The protrusions 50 might alternatively or additionally be found on the end of the connector 60 but it is preferred that they be located on the septum 44 such that rotation of the access hub 56 relative to the port assembly 20 will not impact on the communication through the slit 46 . The connector includes an annular surface 74 which, in cross section as illustrated in FIG. 5 , is shown to provide a segment of a circle. The curved portion of the surface 74 facing toward the distal end of the connector 60 aids in the location of the access hub 56 into the port assembly 20 . The more proximal portion of the annular surface 74 cooperates with a radially resilient bearing ring 76 located within the cavity 28 . Together the annular surface 74 and the radially resilient bearing ring 76 define a coupling between the port assembly 20 and the access hub 56 . The ring 76 is preferably split to create adequate radial resilience. The ring 76 includes an inner concave track 78 meeting with the annular surface 74 . The resilience in the ring 76 and the shape of the concave track 78 cause the ring 76 to draw the connector 60 further into the cavity 28 as the ring 76 attempts to contract. This bias forces the flat end of the connector 60 against the circular bead 54 to result in sealing contact therebetween. The placement of the connector 60 is such that the circular bead 54 is located about the end of the passage 66 . The annular surface 74 is small enough to fit through the port 26 and to force open the ring 76 .
[0039] The port assembly 20 and access hub 56 of this first embodiment provide for the placement of the port assembly 20 in the body prior to an assembly of the port assembly 20 and the access hub 56 . Once assembled, the connector 60 of the access hub 56 is biased against the septum 44 , resulting in the circular beads 52 and 54 sealing against the connector 60 and the cannula mount element 30 , respectively. The distal surface of the connector 60 forces the shaped protrusions 50 toward the cannula 34 to open the slit 46 . Once open, the slit 46 provides communication from the passage 66 to the cannula 34 . Further, the access hub 56 can be pivoted about the centerline of the connector 60 . When the access hub 56 is removed by extraction force transmitted by the tab 68 , the slit 46 returns to the closed position as the force acting upon the shaped protrusion 50 is removed.
[0040] Another port assembly, generally designated 80 , is illustrated in FIGS. 8 and 9 . This port assembly 80 exhibits a flat rather than frustoconical profile. A base 82 again provides a mounting side 84 which may include adhesive 86 . A cannula mounting element 88 is fixed in the base 82 and has a retainer element 90 thereabout which is also fixed in the base 82 . The cannula mounting element 88 retains a cannula 92 much as in the first embodiment. Further, a resilient barrier 94 defined by the circular elastomeric septum 44 as illustrated in FIG. 6 of the first embodiment is held between the cannula mounting element 88 and the retainer element 90 . The retainer element 90 defines a port 96 . The retainer element 90 also defines a post about the port 96 including an annular surface 98 . The surface 98 defines a concave track about the post thus defined.
[0041] An access hub generally designated 100 , can be assembled with the port assembly 80 . The access hub 100 includes a hub 102 having a hub circular periphery 104 . This periphery 104 includes cut-outs 106 diametrically opposed with undercut sides 108 . The cut-outs 106 expose the base 82 so that a pinching of the assembly with the thumb and forefinger will separate the access hub 100 from the port assembly 80 .
[0042] The hub 102 provides a cylindrical cavity 110 which has one portion about the periphery thereof modified for the provision of a fitting 112 . The fitting 112 again provides for infusion tubing (not shown). An inclined asymmetry 114 at the fitting 112 insures that the infusion tubing is not pushed so far into the fitting 112 that a further passageway into the access hub 100 is closed off.
[0043] An inner hub element 116 fits within the cylindrical cavity 110 and defines a connector 118 and a passage 120 . The passage 120 extends from the fitting 112 to through the connector 118 . The passage 120 is formed as a channel in the inner hub element 116 and closed by the hub 102 . Further, the passage 120 extends through the connector 118 . As with the prior embodiment, the connector 118 is insertable to the resilient barrier 94 , operating in the same way as the first embodiment in the influence on opening the valve mechanism associated therewith.
[0044] A retainer 122 is fixed to the inner web element 116 . The retainer 122 is contemplated to extend fully about the inner cavity 124 defined within the inner hub element 116 . The inner hub element 116 and the retainer 122 capture a radially resilient bearing ring 126 within the inner cavity 124 . This bearing ring 126 is preferably split and includes a convex annular bead 128 which cooperates with the annular surface 98 to define a coupling between the port assembly 80 and the access hub 100 . Albeit the location of the elements are inverted, the ring 126 acts in a similar way to that of the first embodiment in that it is sized and arranged to force the connector 118 into sealing contact with the resilient barrier 94 . Again, one of the end surfaces of the connector 118 and the resilient barrier 94 includes shaped protrusions to cause opening of the valve upon placement of the connector 118 in the port 96 .
[0045] A further port is illustrated in FIG. 10 . The access hub 130 is identical to that of the embodiment of FIGS. 8 and 9 . Further, FIG. 8 applies equally to the embodiments of FIG. 9 and FIG. 10 . The port assembly 132 includes a base 134 which is defined by a cannula mounting element 136 and a disk 138 having a cylindrical flange about the outer periphery thereof. Together the mounting element 136 and disk 138 provide a flow area therebetween which is able to reach a plurality of cannulas 142 extending from the mounting surface 144 . These cannulas 142 are rigid but are contemplated to be very short so as to provide dispersed infusion into living tissue or multi-sensor diagnostic access. The cannulas are rigidly fixed within the cannula mounting element 136 . Further, the cannula mounting element 136 provides a broader opening which communicates with the flow area between the plate 136 and the disk 138 for adequate distribution of infusion fluids thereabout.
[0046] FIGS. 11 through 19 provide inserter embodiments. These embodiments are shown to mate with the port assembly 20 . Through slight modification of the seat within which the port assembly is positioned, the embodiments of FIGS. 8 through 10 might also be accommodated. The first two embodiments, FIGS. 11 through 13 and 14 are advantageously configured for disposable use. The embodiment of FIGS. 15 through 17 is most advantageously reusable. Finally, the embodiment of FIGS. 18 and 19 is configured for reusable or disposable use.
[0047] In the embodiment of FIGS. 11 through 13 , the inserter, generally designated 148 , is shown to include a housing assembly including a housing 150 . The housing 150 is conveniently cylindrical with a bore 152 and outwardly extending flanges 154 to define circular attachment surfaces at either end of the bore 152 . First and second closures 156 and 158 can be retained on the flanges 154 . These closures 156 and 158 include a tab 160 such that they are conveniently removably mounted across the bore 152 with adhesive. The closures 156 and 158 are preferably peal-off sheets commonly employed for sterile closures.
[0048] The housing 150 further includes a mount 162 extending across the bore 152 and integrally formed with the housing 150 . The mount 162 is in the form of a plate perpendicular to the axis of the bore 152 . A central hole 164 is provided through the mount 162 to receive a latch discussed below. Two holes 166 elongate in cross section extend to either side of the central hole 164 . These holes are parallel and are located symmetrically about the center axis of the housing. Certain additional holes 168 are provided through the mount 162 for molding purposes.
[0049] The housing 150 further includes stops 170 extending inwardly in the bore 152 and conveniently being diametrically opposed to one another. The holes 168 for molding purposes are aligned with the stops 170 such that molding of the stops 170 is facilitated. Indexing tabs 172 are also diametrically placed to one side of the mount 162 and are also formed as part of the inner wall of the housing 150 . On the other side of the mount 162 , a key 174 extends into the bore 152 and from the mount 162 .
[0050] A latch 176 is positioned to one side of the mount 162 . The latch includes a plate 178 extending substantially across the bore 152 of the housing 150 . Additionally, the latch 176 includes upwardly extending walls 180 forming segments of a cylinder. One of these segments of the walls 180 includes a keyway 182 which receives the key 174 . The keyway 182 has a substantial portion having a first height to receive the key 174 with the latch 176 axially positioned as shown in FIG. 12 . At one point, the keyway 182 is of increased depth parallel to the centerline of the housing 150 which allows the latch 176 to move toward the mount 162 . The walls 180 have three gaps 184 therebetween. One of the walls 180 also includes an undercut section 186 .
[0051] Hooks 188 extend in the opposite direction of the walls 180 from the plate 178 . These hooks 188 include outwardly extending barbs 190 which extend through the central hole 164 in the mount 162 . The barbs 190 have inclined surfaces 192 such that they can be forced into the central hole 164 with the hooks 188 exhibiting some resilience. The barbs 190 on the hooks 188 are spaced such that once inserted through the central hole 164 , they will engage the rim of the hole 164 regardless of the angular orientation such that the latch 176 is permanently captured by the mount 162 .
[0052] Setoffs 194 extend in the same direction from the plate 178 as the hooks 188 . These setoffs 194 are straight and parallel to one another and equally displaced from the axis of the housing. The setoffs 194 match the parallel holes 166 so that the latch 176 may be forced closer to the mount 162 . However, the hooks 188 also each have an inclined surface facing outwardly which inhibits substantial movement of the latch 176 toward the mount 162 from the position a shown in FIG. 12 . In position for use, the latch 176 is oriented such that the standoffs 194 are not aligned with the parallel holes 166 such that the latch 176 is held axially within the bore 152 of the housing 150 . During assembly of the inserter might the latch be angularly rotated to match the setoffs 194 with the parallel holes 166 to insure that assembly can be accomplished.
[0053] A cover 198 is arranged with the latch 176 . The cover also includes a plate 200 which generally lies against the plate 178 of the latch 176 . A cylindrical wall 202 extends upwardly from the plate 200 . This wall 202 includes three blocks 204 which extend radially outwardly from the wall 202 . These blocks 204 engage the gaps 184 in the upwardly extending walls 180 of the latch 176 . Consequently, rotation of the cover 198 will result in rotation of the latch 176 with the two components in mating relationship.
[0054] The cover also includes two fingers 206 diametrically opposed and spaced in cutout portions of the cylindrical wall 202 . One of these fingers 206 includes a rounded circumferentially extending bar 208 which engages the undercut section 186 in one of the upwardly extending wall segments 180 . The bar 208 provides some retention of the cover 198 but allows it to be removable with a small amount of force. The two opposed fingers 206 are slightly shorter than the full extent of the upstanding wall 202 and have inclined surfaces 207 . The fingers 206 are somewhat resilient and can move radially inwardly because of the cuts to either side of the fingers 206 in the cylindrical wall 202 .
[0055] Centrally located in the plate 200 , an integral channel 210 extends across the cover 198 . This integral channel 210 forms a chamber 212 open toward the latch 176 .
[0056] The structure of the cover 198 is such that it can be extracted from association with the latch 176 and pulled from the housing 150 . The cover 198 may then be turned over and forced into the other end of the housing 150 within the bore 152 as seen in FIG. 13 . The fingers 206 resiliently ride over the diametrically opposed stops 170 across the inclined surfaces 207 and lock on the upper surface of the fingers 206 .
[0057] The cylindrical wall 202 has an additional rim 214 about its circumference to fit closely within the bore 152 of the housing 150 in this position. As such, the lower end of the bore 152 is closed by the cover 198 after use. The upper end of the bore 152 remains substantially closed by the plate 178 of the latch 176 .
[0058] A port driver, generally designated 216 , is slidably mounted within the bore 152 of the housing 150 . The port driver 216 includes a cylindrical outer wall 218 which slides within the bore 152 . The cylindrical outer wall 218 includes two gaps (not shown) diametrically opposed. These gaps mate with the indexing tabs 172 which extend from the mount 162 . These gaps also provide clearance to allow the port driver 216 to be mounted in the housing 150 across the stops 170 . The gaps extend fully through the port driver 216 and allow for air flow as the driver 216 moves through the housing 150 . A cylindrical inner wall 220 defines an annular spring cavity 221 for receiving a coil spring 222 . The cylindrical inner wall 220 includes an inwardly extending flange 224 which includes notches 226 diametrically opposed where there is no inwardly extending flange 224 . As such, the hooks 188 which extend through the central hole 164 further extend into the cylindrical inner wall 220 and engage the inwardly extending flange 224 unless aligned with the notches 226 .
[0059] A plate 228 extends across the port driver 216 from which the cylindrical walls 218 and 220 extend to form the annular spring cavity 221 . This plate 228 provides a seat 230 which is shown in FIGS. 12 and 13 to be conically formed to accommodate the first embodiment port assembly 20 . The seat 230 may easily be formed to accommodate the port assemblies 80 and 132 . In this disposable embodiment, the seat 230 does not in any way restrain the port assembly 20 from moving away from the seat 230 . The plate 228 does extend outwardly to the wall of the bore 152 such that the stops 170 will engage the plate 228 as it moves to the end of the housing 150 .
[0060] The plate 228 includes a central portion 232 having holes 234 facilitating the molding process of the flanges 224 . The holes are directly aligned with the inwardly extending flange 224 to that end. A socket 236 is centrally located within the central portion 232 . This socket 236 is sized to receive a needle which may be forcefully fit within the socket 236 or permanently retained there by a bonding agent. In either circumstance, the socket is designed to rigidly and permanently fix a needle employed as a cannula insertion member.
[0061] A cannula insertion member 238 in the form of a sharp needle is permanently affixed within the socket 236 . This needle 238 extends downwardly through the port assembly 20 and through the cannula 34 associated therewith. The cannula 34 is fit snugly about the needle 238 such that friction does exist between the cannula 34 and the needle 238 . The retention force thus provided maintains the port assembly 20 in place prior to application. The adhesive on the mounting side 24 is formulated to have a greater separation force than the retention force between the cannula 34 and the needle 238 . Further, the base 22 is sized to miss these stops 170 .
[0062] In operation, the inserter 148 is assembled by pressing the latch 176 into position with the hooks 188 extending through the central hole 164 . The cover 198 is also positioned on the latch 176 and forced into place. The latch may be oriented such that the parallel setoffs 194 engage the parallel holes 166 so that the latch 176 may be forced further into the bore 152 to insure engagement with the port driver 216 . The coil spring 222 is placed between the mount 162 and the port driver 216 in the annular spring cavity 221 . The port driver is aligned with the housing 150 so that the gaps match up with the stops 170 . With the spring operatively positioned between the mount 162 and the port driver 216 , the port driver is forced upwardly and angularly displaced until the hooks 188 engage the inwardly extending flange 224 .
[0063] The cannula insertion member 238 may originally be part of the inserter 148 by location in the socket 236 with a bonding agent or through forced interference fit. Alternatively, the cannula insertion member 238 may first be temporarily assembled with the port assembly 20 through the cannula 34 and then associated with the port driver 216 as the port assembly 20 is positioned. Ultimately, the cannula insertion member 238 becomes a fixed part of the port driver 216 .
[0064] The closures 156 and 158 are then positioned and fixed on the ends of the housing 150 and the device sterilized. Depending on the method of sterilization, the device is sterilized after placement of the closures 156 and 158 .
[0065] In use, the closures 156 and 158 are removed by pulling on the tabs 160 . The inserter 148 is then placed on the body site. The cover 198 is then rotated until the hooks 188 meet the notches 226 in the inwardly extending flange 224 , releasing the port driver 216 . The spring 222 propels the port driver 216 forwardly to the end of the housing 150 where it engages the stops 170 . The port assembly 20 is advanced with the port driver 216 until the adhesive contacts the surface of the body. In doing so, the cannula insertion member 238 is rapidly advanced into the body along with the supported cannula 34 . Once placed, the housing 150 is retracted from the body retaining the port driver 216 including the cannula insertion member 238 . The resilient barrier 42 prevents flow from the body through the cannula 34 . With the inserter 148 removed, the cover 198 is pulled from the end of the housing 150 and placed on the other end thereof to engage the fingers 206 with the stops 170 . The container 212 defined by the channel 210 receives the cannula insertion member 238 to cover the sharp and close the container.
[0066] With the port assembly 20 in place and the inserter 148 removed, an access hub 56 can then be placed. As the connector 60 is inserted into the port 26 of the port assembly 20 , the end surface of the connector 60 extends against the shaped protrusions 50 of the resilient barrier 42 . The connector 60 does not extend through the slit 46 but opens the valve through its positioning in the cavity 28 . The coupling mechanism including the radially resilient bearing ring 76 and the annular surface 74 is engaged; and the connector 60 is pressed against the circular bead 52 . The access hub 56 is then movable in the port assembly 20 and can be pivoted to best advantage for the associated infusion tubing. Removal of the access hub 56 , in this embodiment by the tab 68 , will withdraw the connector 60 and allow the slit 46 to again close in the resilient barrier 42 .
[0067] Turning to the port driver 240 illustrated in FIG. 14 , the mechanism is substantially identical to that of the embodiment of FIGS. 11 through 13 . However, the cover 242 is differently configured principally with a channel 244 having a container 212 which is askew to bend the cannula insertion member 246 to the side as the cover 242 is placed on the driver end of the housing 248 . Stops 250 again engage the cover 242 to hold it in place.
[0068] Turning to the inserter embodiment of FIGS. 15 through 17 , a reusable inserter, generally designated 252 , is disclosed. The inserter includes a housing 254 which is substantially identical to prior housings. The bore 258 includes a mount 260 extending across the housing 254 as previously described. However, the central hole 262 is increased in size for placement considerations.
[0069] The port driver 264 includes a cylindrical outer wall 266 and a cylindrical inner wall 268 defining an annular spring cavity 270 . Inwardly extending flanges 272 are located at the end of the cylindrical inner wall 268 most adjacent the mount 260 . Again, notches 274 in the inwardly extending flanges 272 are arranged diametrically. A coil spring 276 is located within the annular spring cavity 270 . In this embodiment, the center area of the port driver 264 is open. An annular plate 278 closes the bottom of the annular spring cavity 270 and defines a seat for a port assembly 20 . In this embodiment, the base 282 of the port assembly 20 includes a circular channel 284 . The seat 280 of the annular plate 278 includes a retainer 286 in the form of a circular ring which engages a circular channel 284 with minimal release force generated by a minimal interference fit to retain the port assembly 20 in place prior to insertion.
[0070] The cannula insertion member 288 includes a sharpened needle 290 and a needle hub 292 . The needle 290 is permanently retained within the needle hub 292 . The needle hub 292 includes an engagement shoulder 294 at its distal end and a plug 296 that fits within the port 298 of the port assembly 20 .
[0071] A latch 300 is located to the other side of the mount 260 from the port driver 264 . The latch includes a plate 302 extending across the bore 258 of the housing 254 . A cylindrical wall 304 extends along the bore 258 . A keyway 306 is found in the cylindrical wall 304 to receive a key 307 associated with the housing 254 . Hooks 308 are provided as in prior embodiments but are spaced further apart to allow for the needle hub 292 .
[0072] A socket 310 is centrally located in the plate 302 of the latch 300 . This socket 310 releaseably retains the needle hub 292 which is otherwise slidable within the socket 310 . The socket 310 includes a passageway 312 which is open at the end toward the port assembly seat 280 . A shoulder 314 is presented at the end of the passageway 312 to encounter and retain the engagement shoulder 294 of the needle hub 292 . The socket 310 is also split diametrically along its length to form two socket elements 316 . The length of the socket 310 is such that, in combination with the needle hub 292 , the engagement shoulder 294 and the shoulder 314 do not stop insertion of the cannula insertion member until the needle 290 has penetrated the body to the point that the associated cannula 34 will not extend beyond the needle 290 . The arrangement is designed to stop the cannula insertion member 288 before the port driver 264 has traveled fully to the stop 318 located in the bore 258 of the housing 254 .
[0073] With the inserter 252 having been actuated by rotation of the latch 300 and the port assembly 20 placed, the inserter 252 can be withdrawn along with the cannula insertion member 288 as a component of the inserter 252 . Once withdrawn, the cannula insertion member 288 can be released from the reusable inserter 252 . The plate 302 defines a slightly flexible web across the bore 258 of the housing 254 . Two opposed levers 320 extend upwardly from that web 302 . These levers are aligned with the socket elements 316 defining the socket 310 . By pinching the levers 320 together, the socket elements 316 splay apart and release the needle hub 292 . A new cannula insertion member 288 can then be positioned in the inserter 252 by forcing it past the shoulder 314 . This may be accomplished with or without the port assembly 20 .
[0074] With the reusable inserter 252 , the device may be prepared by positioning the cannula insertion member 288 in the port assembly 20 . The cannula insertion member 288 is then engaged with the socket 310 by forcing the needle hub 292 through the shoulder 314 on the socket elements 316 . These levers 320 may be pinched together to facilitate this assembly. The port assembly 20 is then forced against the port driver 264 to place the port assembly 20 in the seat 280 with the circular channel 284 and the circular ring 286 engaged with slight interference. Where the port assembly has exposed adhesive on the mounting side 322 , it is advantageous that the port driver 264 is forced into engagement with the latch 300 before placement of the port assembly 20 . Once prepared, the inserter 252 may be placed at the site and the levers 320 turned to rotate the latch 300 such that the hooks 308 meet the notches 274 and release the port driver 264 . The inserter 252 is then withdrawn, retaining the cannula insertion member 288 as part of the inserter assembly. The port assembly 20 remains at the site with the cannula 34 extending into the living body. An access hub 56 is then positioned with the connector 60 in the port 26 . Force is applied to engage the coupling between the two such that the access hub 56 is then movably retained within the port assembly 20 . The system is then ready for delivery of therapeutic agents or diagnostic agents through the cannula into the living tissue. The access hub 56 may be withdrawn through force exerted on the tab 68 , or by pinching the access hub in the second or third embodiments. The valve of the resilient barrier 42 responds appropriately by sealing the pathway when the access hub 56 is not in place and opening the pathway when it is.
[0075] A further port inserter as illustrated in FIGS. 18 and 19 , generally designated 324 , combines a number of features of the prior port inserters. The device may come fully sealed and sterile. Further, the port inserter 324 contemplates the intended release of the needle after use or the enclosure of that needle with the inserter for discard. A cylindrical housing 326 , as generally described in preceding embodiments, includes an extended length to accommodate closure elements 328 and 330 . A latch 332 operates identically to that in the prior embodiment of FIGS. 15 through 17 and cooperates with a needle hub 334 and needle 336 in a like manner. The extended portion of the housing 326 encloses the levers of the latch 332 and receives a cover 338 . This cover is constructed so that it may be forced against the driver 340 from the bottom to enclose the needle 336 and lock the cover over the stops 342 . The driver 340 is the same as that of prior embodiments and is driven by a spring 344 in like manner. Likewise a port 20 also is as in prior embodiments.
[0076] Thus, improved ports and inserters therefor have been described. While embodiments and applications of this invention have been shown and described, it would be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein. The invention, therefore is not to be restricted except in the spirit of the appended claims. | A system for delivery of therapeutic and/or diagnostic agents into a living body includes a port assembly having a cannula extending from the mounting side, a port opening away from the mounting side and a resilient barrier between the port and the cannula. An access hub includes a connector positionable at the port for opening the resilient barrier. The access hub is movable in the port assembly, is engaged therewith through a resilient ring coupling and forms a seal with the resilient barrier, reducing the amount of volume to be primed. Inserters, both disposable and reusable, include the cannula insertion member as part of the assembly. A spring loaded port driver is operatively mounted within the housing with movement controlled by a latch. The driver includes a seat for receipt of a port assembly. The cannula insertion member is nonremovably fixed in a socket in the port driver in the disposable assembly. In the reusable inserter, the cannula insertion member is slidably mounted within a socket associated with the latch. Slidable movement is limited by locking shoulders. The socket is split and may be splayed to release the cannula insertion member following use. | 0 |
This is a continuation of application Ser. No. 438,238, filed Nov. 20, 1989, now abandoned, which in turn was a continuation of Ser. No. 292,823, filed Jan. 3, 1989 which has now issued as U.S. Pat No. 4,910,979.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an automatic clothes washer and more particularly to a vertical axis washer having an agitator and wash basket.
2. Description of the Prior Art
In conventional vertical-axis automatic washers, there is a central agitator which oscillates during the wash portion of the cycle within a wash basket holding the materials to be washed, the wash basket being held in a fixed position relative to the washer cabinet by a brake. For example, U.S. Pat. No. 3,216,227 discloses a direct drive motor that drives an agitator by means of the motor shaft and drives the basket by means of a coupling between the motor housing and the basket. The basket is locked by a brake mechanism during agitation.
In other constructions the basket does move during agitation, but either there is no agitator present, or else the basket moves with the agitator.
U.S. Pat. No. 3,066,521 discloses an automatic washer in which there is no vertical axis agitator, but rather the basket itself is rotated periodically during the wash operation to effect mechanical agitation of the clothes load.
U.S. Pat. No. 3,648,486 discloses an automatic washer wherein a central agitator is affixed to the basket and both the basket and agitator move together during the agitation portion of the wash cycle.
SUMMARY OF THE INVENTION
The present invention provides a drive system for an automatic washer where a reversing drive system consisting of a reversing motor in the preferred embodiment, is coupled to a planetary gear set, the motor input being coupled the sun gear. A ring gear is directly coupled to the basket and a planet carrier output is coupled to the agitator. As the motor rotates in one direction, it drives the agitator in the same direction. Unlike conventional washer operation, however, the basket is not held stationary, that is, the basket brake is not engaged during agitation. With no fixed member to provide a reactionary force, the ring gear and basket are driven in a direction opposite to that of the agitator. When the motor reverses, so does the direction of the agitator and basket, resulting in a dual-agitation or counter-rotation between the agitator and basket. That is, the agitator and basket will always rotate or oscillate in opposite directions. Since the inertia of the basket is greater than that of the agitator, the basket will rotate much less than the agitator. A typical system may have have an agitator stroke angle of 180°-240° and a basket rotation of 20°-60° . The amount of the basket rotation is dependent upon the system inertia, friction, angle of agitator stroke, and clothes load size.
The advantages of such a system include a 25-40% reduction in agitate torque force required by the motor for a given load size, elimination of the need for a brake or mechanical reaction force during agitation, lessening of the shock loading on gears, allowance for a uniform (symmetric) rotation of the basket during agitate, and elimination of tub motion during agitation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective of an automatic washer embodying the principles of the present invention.
FIG. 2 is a side sectional view of the agitator and drive system of the washer of FIG. 1.
FIG. 3 is a top elevational view schematically illustrating movement of the agitator and basket during an agitate portion of the wash cycle.
FIG. 4 is an enlarged sectional view the planetary drive connection.
FIG. 5 is a sectional view taken generally along the line V--V of FIG. 4.
FIG. 6 is a schematic illustration showing the rotational inertias of the basket and agitator.
FIG. 7 is a graphic illustration of the amount of basket rotation relative to the clothes in the basket for a fixed motor angle input.
FIG. 8 is a graphic illustration of the amount of basket rotation relative to clothes load in the basket for a fixed motor torque input.
FIG. 9 is a graphic comparison of torque input required for varying load in a conventional wash versus torque input required in a washer incorporating the principles of the present invention.
FIG. 10 is a graphic comparison of stroke angles of the agitator and rotation of the basket for varying sized loads.
FIG. 11 is a graphic comparison of motor shaft rotation to the agitator and basket rotation of FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 there is illustrated an automatic washer generally at 10 enbodying the principles of the present invention. The washer has an outer cabinet 12 with an openable lid 13 which encloses an imperforate was tub for receiving a supply of wash liquid. Concentrically mounted within the wash tub is a wash basket 16 for receiving a load of materials to be washed and a vertical axis agitator 18. A motor 20 is provided which is drivingly connected to the agitator 18 to drive it in an oscillatory or rotary manner and is also selectively connectable to the basket 16 to rotate or, in a preferred embodiment, to oscillate it. The assembly of tubs, agitator and motor is mounted on a suspension system 22. A plurality of controls 26 are provided on a control 28 for automatically operating the washer through a series of washing, rinsing and liquid extracting step as is well known in the art.
A reversible drive system is provided which includes means for oscillatingly driving the agitator during a washing mode and means permitting said basket to rotate relative to the washer cabinet and the agitator in the washing mode. The means for oscillatingly driving the agitator preferably is operatively connected between the reversible drive system and the basket and agitator.
The preferred embodiment of a drive mechanism is shown in greater detail in FIGS. 2 and 4 where it is seen that the motor 20 is connected by means of a drive belt 30 through a gear arrangement, such as a planetary gear assembly 32, to a vertical shaft 34 connected to the agitator 18. Alternatively, the motor 20 may be directly coupled to the gear assembly 32. Also, other types of gear arrangements may be utilized to provide a drive means between the reversible drive system and the basket and agitator for selectively rotationally driving the agitator and basket in opposite and common directions. In this preferred embodiment, the motor 20 is a permanent split capacitor (PSC) motor which is to be reversely operated to provide the oscillatory motion to the agitator 18 and the basket 16. Alternatively, the wash basket 16 is connected via a spin tube 36 to the gear arrangement 32 such as to an outer ring gear 37 having an external hub surface 44. The vertical shaft 34 is connected to planet gears 40 through the use of a connecting carrier plate 42 and a sun gear 46 is directly connected to a shaft 48 connected to a pulley 50 which is rotated by the belt 30 connected to the motor 20.
When the washer is operating in the agitate mode, the motor 20 is operated in a reversing fashion which causes the shaft 48 to oscillate, thus driving the sun gear 46 in alternating opposite directions. The agitator is therefore oscillated through its connection with the planet gears 40 and the wash basket 16 is oscillated, rotationally opposite to the agitator, through its connection to the outer ring gear 37. Since the inertia of the basket 16 with its liquid and clothes load is greater than the inertia of the agitator, taking into account the effect of the clothes load, (FIG. 6), the basket will rotate much less than the agitator. As FIG. 3 illustrates, the agitator, in a preferred embodiment may rotate through a stroke angle A of 180°-240° while the basket rotation angle B will be around 20°-60°.
Referring again to FIG. 4, when the washer is operating in the spin mode, a clutch 52 is provided to rotationally lock the ring gear 37 with the shaft 48 so that the basket 16 and the agitator 18 will spin together. The clutch includes an axially displaceable gear member 54 having teeth 56 on an outer circumference thereof which engage with corresponding teeth 58 on an annular axial extension 60 of the ring gear 37. The displaceable gear 54 has a plurality of axially aligned teeth 62 on an inner surface 63 thererof which are engageable with outwardly projecting axially agligned teeth 64 carried on the shaft 48. Axial movement of the gear 54 will selectively engage or disengage the gear teeth 62 with the shaft teeth 64. When the gear teeth 62 are engaged with the shaft teeth 64, the ring gear 34 will be rotationally locked to the shaft 48. When the teeth 62 are disengaged, the ring gear 37 will be free to rotate relative to the shaft 48.
An axially moveable actuator arm 66 is provided to move the gear 54 away from the shaft teeth 64 when desired, such as in the agitate mode. A coil spring 68 is provided between the gear 54 and the ring gear 37 to urge the gear 54 back into engagement with the shaft teeth 64 to lock the ring gear 37 rotationally to the shaft 54, such as during the spin mode. FIG. 4 illustrates the position of gear 54 in the unlocked or agitate mode and FIG. 2 illustrates the position of the gear 54 in the locked or spin mode.
A band brake 70 is provided which encircles the hub surface 44 of the ring gear 37. This band brake, unlike band brake mechanisms in prior washers, is not operated when the washer is isn the agitate mode, but rather is only operated when the lid 13 is open. During this event, the band is tightened to frictionally engage the hub and prevent is rotation, thereby preventing rotation of the basket.
In standard planetary drive arrangements, the drive force applied to the sun gear generally works against a reaction force represented by a fixed ring gear. It was expected that if the basket were unrestrained, thus removing the fixed reaction force, the agitator motion and stroke would drop off and uncontrollable basket motion would result. Surprisingly, however, in the arrangement of the present invention, a first torque load (arrow 72, FIG. 6) represented by the basket inertia and the effect of the water and clothes load on the basket balances with a second torque load (arrow 74) represented by the agitator inertia and the effect of the water and clothes load on the agitator to provide control to the oscillating motion with the ratio of the torque loads provideing the ration of stroke angles. The effective sum of the first basket torque 72 and second agitator torque 74 equals through the gear reduction a torque input (arrow 76) of the motor 20.
In conventional systems, a portion of the energy output of the motor is lost due to the braking of the motion of the basket 16 as the agitator 18 oscillates. With the present arrangement, more of the energy goes into the wash system thereby permitting a reduced total energy consumption for an agitate cycle.
FIG. 9 shows a comparison of torque input for varying sized wash loads with line 80 representing the empirical test results for a conventional washer wherein the basket is braked during agitation and with line 82 representing the results for a washer incorporating the principles of the present invention wherein the basket is not braked. It is clear from the experimental results that torque input is substantially reduced when the basket is reversely driven relative to the agitator rather than merely braked.
The size of the clothes load has an effect on the ratio of rotational movement as is illustrated in FIGS. 7 and 8 which show the amount of angular basket (α), agitator (β) and motor shaft (υ) movement as they relate to the changing of load size. FIG. 7 represents the results for the drive arrangement when the motor is operated for constant angle input while FIG. 8 represents a motor that reacts to the load by providing a reduced angle as the load increases.
With no clothes in the washer, there is no coupling between the agitator 18 and the basket 16 and there is minimal inertia of the agitator. Thus, most of the drive torque goes to the agitator, having the least inertia, and basket movement is at a minimum since it has a large inertia. The ratio of agitator rotational inertia to basket rotational inertia corresponds directly to the ratio of agitator rotation to basket rotation, through gear case reduction ratio. As clothes are added to the washer, those clothes are carried by the agitator, thus adding to the torque load of the agitator and thus increasing the rotational inertia of the agitator, thereby increasing the portion of the drive torque going to the basket. This increases the angular movement of the basket. As still further clothes are added, coupling between the agitator and basket through the clothes causes less excursion of the basket. That is, the basket inertia increases relative to the agitator inertia. As still more clothes are added, clothes see "longer" stroke angles because of coupling of the clothes to the wash basket. The combination of the rotational angles of the agitator and basket corresponding to the motor shaft angle, becomes the effective or total relative stroke angle even though the agitator is driven through a much shorter stroke angle. Thus, there is no decrease in mechanical agitation even if there is a decrease in the stroke angle of the agitator. This provides for reduced energy consumption for a given effective stroke angle.
FIG. 10 is an empirical comparison of agitator rotation illustrated by line 84 and basket rotation illustrated by line 86 for increasing load sizes. FIG. 11 again shows agitator and basket rotation as well as motor angle at line 88. It can be seen that at high load levels, although the motor is stressed, the rotational angles of the basket and agitator do not decrease dramatically.
Since there is no restraint placed on the wash basket and ring gear, the shock loading on the gears is greatly lessened and tub motion is eliminated.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceeding specification and description. It should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope. | A counter-rotation wash system is provided in an automatic washer wherein the basket and agitator are reversely oscillated during a wash mode and the basket and agitator are co-rotated during a liquid extraction or spin mode. A reversing PSC motor is connected through a planetary device to both the agitator and basket with the basket being free from restraint during the agitate mode. Reduced torque requirements and other advantages accrue. | 3 |
TECHNICAL FIELD
This invention relates generally to an adjustment control system for a grain cleaning sieve or sieves of an agricultural combine, and more particularly, to a method of automatic operation of a sieve control system for adjusting the sieve opening size or position while mitigating error and inaccuracy resulting from tolerance stack-up of mechanical components in the system.
BACKGROUND ART
It is well known to provide an automatic system for adjusting the sieve or sieves of the grain cleaning system of an agricultural combine. Typically, the cleaning system will consist of two sieves, an upper or coarser sieve or chaffer located below the threshing mechanism or separator of the combine and having larger sieve openings for the passage of grain and smaller pieces of plant material therethrough but relatively little of the larger chaff, and a lower finer sieve located below the chaffer for receiving the grain and smaller pieces of plant material therefrom and having smaller sieve openings for passage of the grain therethrough but relatively little of the plant material. The collected and cleaned grain, once through the sieves is then typically transported by conveyor or other means to a clean grain bin on the combine, or to an accompanying grain receiving vehicle. The opening sizes of the chaffer and sieve are an important parameters for controlling the amount or yield of grain that is recovered by the combine as opposed to discharged therefrom with the chaff and other unwanted plant material and crop residue. Accordingly, the chaffer and sieve opening sizes are typically set at the commencement of the harvesting operation, and may be reset at times during the harvesting operation, to achieve a desired crop yield rate.
A typical sieve construction includes a plurality of elongate parallel, pivotally mounted slats, each slat including a plurality of longitudinally spaced upwardly extending inclined fingers, the slats being pivotable through a range of open positions angularly oriented to horizontal for providing a corresponding range of openings or spaces between the fingers of adjacent ones of the slats. A typical automatic sieve adjusting system includes an adjusting member which contacts each of the slats, and a linkage and/or cable arrangement connected between the adjusting member and one or more actuators driven by an electrical, fluid, or other controller for moving the linkage or cable arrangement and member and thus changing the angular orientation of the slats and as a result, the opening size. The typical controller includes at least one processor operated by stored commands and/or inputs for controlling an electrical drive motor or the like for moving the actuator. An input device such as a push button or keypad and a display device are typically located in the operator cab of the combine for changing and showing the chaffer and sieve settings.
Typical sieve control systems are disclosed in Rowland-Hill et al. U.S. Pat. No. 4,466,231, issued Aug. 21, 1984 to Sperry Corporation; and Diekhans U.S. Pat. No. 6,205,384, issued Mar. 20, 2001 to Claas Selbstfahrende Erntemaschinen GmbH. U.S. Pat. No. 4,466,231 in particular discloses a method for automatic sieve and chaffer adjustment which ensures that the approach to the final position or setting is always made in the direction for opening the sieve, thereby allowing for compensation for play or backlash in the mechanical linkages of the system. However, to reduce the probability of the sieve or chaffer being damaged by crop material or foreign objects as it is moved to the setting, the sieve or chaffer is brought to a fully open position so as to pass any large and potentially damaging objects therethrough, then is moved in a closing direction to a more closed position past the desired setting by an amount corresponding to an anticipated amount of backlash or play in mechanical components of the system. Then, the sieve is opened by a corresponding amount to the desired setting. Possible shortcomings of this method of operation, however, include in the instance of a chaffer, the possible passage of larger pieces of plant material, such as stalk and stem fragments, into the openings of the chaffer so as to be caught or trapped therein or suspended therefrom, so as to decrease the capacity thereof as well as possibly also interfere with the operation of the sieve below, so as to reduce the capacity or efficiency of the cleaning system. In the instance of the lower finer sieve, if fully opened during the operation thereof when larger crop material is present thereon, the undesirable crop material can pass with the grain through the sieve so as to increase the percentage of impurities in the clean grain. This may be acceptable on an occasional basis. However, if it is desired to more frequently adjust the opening size of the finer sieve, for instance, such as for automatically maintaining a selected sieve opening size, more frequently fully opening the sieve may significantly increase the amount of unwanted crop material in the clean grain.
Accordingly what is sought is a system for automatically adjusting a sieve of an agricultural combine which overcomes many of the problems and shortcomings set forth above.
SUMMARY OF THE INVENTION
According to one aspect of the invention, a method of automatically controlling an opening size of a sieve of an agricultural combine is disclosed, which overcomes many of the problems and shortcomings identified above. The present method includes the steps of:
(a) storing a value for the opening size;
(b) determining an actual value for the opening size;
(c) comparing the actual value with the stored value, and,
(i) if the actual value is at least a predetermined amount greater than the stored value, then automatically closing the sieve until the actual value equals the stored value;
(ii) if the actual value is greater than the stored value by less than the predetermined amount, then automatically opening the sieve until the actual value is a predetermined amount greater than the stored value, then automatically closing the sieve until the actual value equals the stored value; and
(iii) if the actual value is less than the stored value, then automatically opening the sieve until the actual value is a predetermined amount greater than the stored value and then automatically closing the sieve until the actual value equals the stored value.
Preferably, the predetermined amounts are each an amount which correspond to or is only slightly or marginally greater than the amount of the anticipated tolerance stack-up for, or play in, the mechanical components of the system. The typical range of opening sizes for a particular sieve will equal several times the cumulative tolerance stack-up or play for the mechanical components of the system, which provides the advantage when the selected opening size is relatively small or in the lower portion of the range, that the sieve is only further opened by a relatively small amount, thereby limiting the number of larger pieces of plant material or contaminants that may be passed through or could become jammed or lodged in the sieve or chaffer, and the amount of smaller crop residue that would pass through the finer sieve with the clean grain. Also, because the sieve is only open a relatively small amount greater than the desired opening size, the adjustment can be completed in a time period shorter than required for opening the sieve from a smaller opening size to the fully opened position, closing the sieve to an opening size smaller than the desired size, then opening the sieve to the desired opening size, such as disclosed in U.S. Pat. No. 4,466,231.
As a preferred optional step, the sieve can be opened or closed to a commanded opening size, then a value for the commanded opening size stored for use as the stored value. Also preferably, during the prior step, the threshing mechanism or separator of the combine is not operating, such that any substantial flow of material therefrom to the sieve is absent. This allows the sieve to be moved, for instance, using an operator input device such as a push button or keypad, in an opening direction, a closing direction, or alternatively in both, for setting the sieve to a desired opening size without risk of becoming jammed with material therein or too large of material passing therethrough. Then, steps (a), (b) and (c) can be performed during the operation of the sieve when a flow of material from the separator is present, for making minor size adjustments for maintaining the sieve opening size at the desired value or setting.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified side elevational view of an agricultural combine including a sieve adjustment control system operable according to the method of the present invention;
FIG. 2 is a simplified schematic diagram of the control system;
FIG. 3A is a high level flow diagram showing steps of the method of the invention.
FIG. 3B is a continuation of the flow diagram of FIG. 3 A.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, in FIG. 1 a conventional agricultural combine 10 is shown including a sieve adjustment control system 12 operable according to the teachings of the present method. Agricultural combine 10 generally includes a threshing mechanism or separator 14 operable for receiving crop material from a harvesting mechanism 16 and separating smaller grains, seeds, pods and related plant material from larger stalks, stems, leaves, husks and other elements of the crop material, as well as vines, weeds and the like which may be present in the harvested crop material. The smaller material falls from separator 14 into one or more augers 18 disposed below separator 14 , which collect the smaller material and convey it to a cleaning system 20 . Cleaning system 20 includes an upper, coarser sieve or chaffer 22 positioned for receiving the material from auger or augers 18 , as denoted by arrow A, and a lower, finer sieve 24 which receives grain or seeds which pass through chaffer 22 . Sieve 24 , in turn, separates or cleans the grain or seed from the remaining other material, such as pod fragments and the like, for collection by a lower auger 26 which conveys the clean grain or seeds to an elevator 28 which conveys the clean grain or seeds upwardly to a clean grain bin 30 . Chaffer 22 and sieve 24 are vibrated or reciprocated during operation by suitable means (not shown) for facilitating sifting of the crop material therethrough. Material which does not pass through is moved rearwardly on chaffer 22 or sieve 24 by the vibration or reciprocal action and is either blown or drops from the rear end thereof through an opening in the rear of combine 10 or into a return auger 32 and be carried to a return elevator 34 for conveyance back to separator 14 .
Referring also to FIG. 2, chaffer 22 and sieve 24 , represented by sieve 24 , each include a plurality of elongate, horizontally extending slats 36 , each slat being pivotable about a generally horizontal pivotal axis 38 . Each slat 36 is composed of a plurality of parallel, longitudinally spaced upward and downwardly inclined fingers 40 , the fingers 40 of adjacent ones of slats 36 defining sieve openings therebetween, represented by distance X in FIG. 2, for the passage of only plant material of a desired maximum size therethrough. Slats 36 are simultaneously pivotable about respective pivotal axes 38 through a range of pivotable positions for varying the opening size X of the sieve in the well known conventional manner, as denoted by arrows B. In this regard, slats 36 would be pivoted in a counterclockwise direction to increase the opening size X, and pivoted in the clockwise direction for decreasing the opening size X.
Sieve adjustment control system 12 is operable for automatically and simultaneously moving slats 36 through a predetermined range of pivotal positions for varying the opening size of sieve 24 , and for holding slats 36 at a position corresponding to a desired or selected opening size. To accomplish this, system 12 preferably includes at least one actuator 42 , such as, but not limited to, a conventional electric linear actuator (ELA). Actuator 42 can be connected by a suitable mechanical connecting element such as one or more cables and/or linkages, to an adjusting member 46 of sieve 24 . Adjusting member 46 will typically include a plurality of upwardly extending portions 48 which contact and support slats 36 for pivotal movement about pivotal axis 38 thereof, respectively, adjusting member 46 being linearly movable by connecting element 44 in the direction denoted by the arrow C for moving slats 36 in an opening direction, and in the direction denoted by the arrow D for moving slats 36 in a closing direction. Accordingly, actuator 42 is precisely controllably movable in a corresponding linear manner in the direction C for effecting movement of connecting element 44 and adjusting member 46 and thus slats 36 in the opening direction, and in direction D for effecting movement of connecting element 44 , adjusting member 46 and slats 36 in the closing direction.
Actuator 42 can be controlled using any suitable conventional controller, such as, but not limited to, controller 50 shown including at least one microprocessor and related circuitry drivingly connected to a motor connected to actuator 42 and operable for moving actuator 42 in the direction C and D, or holding actuator 42 at a selected position. Controller 50 is conventionally operable for moving actuator 42 based upon commands received from a suitable input device 52 which can be, for instance, a conventional push button or keypad device, or another input device, or a stored command or value contained in a suitable memory or register, such as a register of a display device 54 , input device 52 and display device 54 being connected to controller 50 by a suitable conductive path 56 such as a conventional wiring harness or the like. Input device 52 and display device 54 will typically be located in an operator cab of combine 10 . Information representative of a position of actuator 42 , adjusting member 46 , fingers 40 and/or slats 36 , which in turn, is representative of the sieve position or opening size, is determined by a suitable position sensor 58 and is accessible or readable by controller 50 via conductive path 56 . Controller 50 is then operable to compare information representative of a commanded or stored position or opening size from device 52 or 54 , with information representative of an actual or sensed position or opening size as determined by position sensor 58 , and controllably operate the motor of controller 50 for holding or moving actuator 42 and thus connecting element 44 , adjusting member 46 and slats 36 .
Here, it should be noted that structurally and operationally, chaffer 22 , is an analogous device to sieve 24 , that is, it is also a sieve, and can be automatically controlled by control system 12 , utilizing a second actuator 42 , mechanical connecting element 44 , controller 50 and position sensor 58 operable in the above-described manner, or by a second control system 12 , or other control system, as desired. In the former instance, a suitable switch or other means can be provided on the operator cab or at another desired location to allow switching devices 52 and 54 between chaffer 22 and sieve 24 , as desired or required.
In a sieve such as chaffer 22 or sieve 24 , the various mechanical apparatus thereof, represented by slats 36 , fingers 40 , connecting elements 44 , adjusting members 46 and upwardly extending portions 48 , are all manufactured to dimensions within certain tolerance ranges. There may also be play designed into the components of these elements and connections therebetween. Actuator 42 may also be operable for holding or moving to a position within a known range. The cumulative value of all, or selected ones, of these tolerances, play and range, can comprise what is referred to herein as a tolerance stack-up.
In operation, at the commencement of a harvesting operation, or at a desired time during the operation, the operator may view the information displayed by display device 54 representative of the opening size or position of slats 36 of chaffer 22 or sieve 24 . Based on the displayed information, the operator may elect or determine to change the opening size by changing the position of slats 36 , and initiate such change using input device 52 .
Referring also to FIGS. 3A and 3B, a high level flow diagram 60 of steps of a preferred method of the present invention are shown. According to the preferred method, after initiation of operation as denoted at start block 62 , controller 50 determines whether an open or close command from input device 52 is present, as shown by decision block 64 . If an open or close command is present, controller 50 will determine whether separator 14 is operating or not, as shown at decision block 66 . As long as separator 14 is operating, controller 50 will loop back to start block 62 and decision block 64 . If separator 14 is not operating, or ceases operating, and an open or closed command is present, controller 50 will then determine whether the command is an open or close command, as denoted by decision block 68 . If the command is an open command, controller 50 will determine whether the actual or current position is less than a predetermined value, preferably corresponding to a maximum opening size or position as denoted at decision block 70 . If the actual position is not less than the predetermined value corresponding to the maximum opening size or position (predetermined maximum value), controller 50 will loop back to start block 62 . If the actual position is less than the predetermined maximum value, controller 50 will operate actuator 42 to move in an opening direction, as denoted at block 72 , to effect a corresponding movement of connecting element 44 , adjusting member 46 and slats 36 , until a desired opening size or position of slats 36 is reached, which will be indicated by display device 54 . Here, it should be noted that the open command can be the result of an inputted value, that is, a desired value inputted via input device 52 if a keypad, or if a push button device, by holding the push button in a particular position until a desired value is displayed by display device 54 . Alternatively, the input command could be recalled from the register or display device 54 or automatically determined by controller 50 , as desired. When actuator 42 has opened the sieve sufficiently to achieve the desired or commanded opening size or position as determined or sensed by sensor 58 and displayed by device 54 , that size or position can be held, and information or a value representative of the actual opening size or position stored in the register of device 54 , as denoted at block 74 , and controller 50 will loop back to start block 62 .
Referring again to block 68 , if it is determined that the command is a close command, controller 50 will determine if the actual opening size or position of slats 36 is greater than a predetermined value, preferably a minimum value representative of a minimum open position or a closed position, as denoted at decision block 76 . If the actual opening size or position is not greater than the predetermined value representative of the minimum open position or closed position (predetermined minimum value), then controller 50 will loop back to start block 62 . If the actual opening size or position is greater than the predetermined minimum value, then controller 50 will controllably operate actuator 42 to move the sieve in the closing direction, as denoted at block 78 , until the commanded or desired opening size or position is reached. The actual position value determined or sensed by sensor 58 will then be stored in the register of display device 54 as denoted at block 74 and controller 50 will return to block 62 .
In the absence of an open or close command, as determined at block 64 , controller 50 will proceed to compare the then existing stored position value with the actual position value, as denoted at block 80 . If those values are equal, controller 50 will return to block 62 . If those values are not equal, controller 50 will determine whether the stored value is less than or greater than the actual value, as denoted at decision block 82 in FIG. 3 B. If the stored position value is greater than the actual value, controller 50 will next determine whether the actual value equals a predetermined value, as denoted at decision block 84 , which is preferably a predetermined high value. If the actual value equals this predetermined high value, then controller 50 will operate actuator 42 in an open direction until the stored value and the actual value are equal, as denoted at block 86 , and then will return to block 62 . If the actual value does not equal the predetermined high value, then controller 50 will operate actuator 42 in the opening direction until the actual value is a predetermined amount greater than the stored value, as shown at block 88 . This predetermined amount greater than the stored value preferably corresponds to or is marginally or slightly greater than the tolerance stack-up, or may be some other desired value. Then, controller 50 will operate the actuator in the closing direction until the stored value and the actual value are equal, as denoted at block 90 , and return to block 62 .
Referring again to block 82 , if controller 50 determines that the stored position value is less than the actual value, it will next determine if the difference between the actual position value and the stored position value equals another predetermined value, as denoted at decision block 92 . If yes, controller 50 will operate actuator 42 in the opening direction until the actual value is the predetermined amount greater than the stored value, as shown at block 88 , then will operate actuator 42 in the closing direction until the stored position value equals the actual value, as shown at block 90 and then return to start block 62 . If, at block 92 , the difference between the actual value and the stored position value does not equal the predetermined value, then controller 50 will operate actuator 42 in the closing direction until the stored value and the actual value are equal, as shown at block 90 , and then return to block 62 .
Thus, according to the method of the present invention two routines are utilized for controlling sieve opening size, one for opening or closing the sieve to reach a commanded position or opening size, and a second routine for monitoring a value representative of an actual sieve position or opening size and if greater than or less than a stored value, then effecting a change in the sieve position or opening size such that the actuator value will equal the stored value. In this latter routine, if the stored value is less than the actual value by at least a predetermined amount, which amount, again, preferably corresponds to or is slightly greater than the tolerance stack-up, the sieve will be actuated to move in a closing direction to reach the position or opening size corresponding to the stored value; if the stored value is not at least the predetermined amount less than the actual value, the sieve will be actuated to open until the actual value is the predetermined amount greater than the stored value, then closed until the stored value and actual value are equal. On the other hand, if the stored value is greater than the actual value but not equal to a predetermined value, preferably a maximum value, the sieve will be opened until the actual value is a predetermined amount greater than the stored value then closed until the actual value and the stored value are equal. In this way, when adjusting the sieve position or opening size to correspond to the stored value, the sieve is always moved in a closing direction by at least the predetermined amount which preferably corresponds to at least the amount of the tolerance stack-up for the mechanical components of the system.
It will be understood that changes in the details, materials, steps, and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention. Accordingly, the following claims are intended to protect the invention broadly as well as in the specific form shown. | An adjustment control system for a grain cleaning sieve or sieves of an agricultural combine, a method of automatic operation of a sieve control system for adjusting the sieve opening size or position while mitigating error and inaccuracy resulting from tolerance stack-up of mechanical components in the system. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 15/180,645, filed Jun. 13, 2016, now U.S. Pat. No. 9,656,608, which is a continuation of U.S. patent application Ser. No. 14/942,087, filed Nov. 16, 2015, now U.S. Pat. No. 9,376,060, which is a continuation of U.S. patent application Ser. No. 13/800,677, filed Mar. 13, 2013, now U.S. Pat. No. 9,191,574, which is a continuation of U.S. patent application Ser. No. 12/708,079, filed Feb. 18, 2010, now U.S. Pat. No. 8,405,725, which is a continuation of U.S. patent application Ser. No. 10/209,181, filed Jul. 31, 2002, now U.S. Pat. No. 7,697,027, which claims priority from U.S. provisional patent application Ser. No. 60/309,023, filed on Jul. 31, 2001, the disclosure of which is hereby incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] This invention is directed to a video processor made for a vehicular video system and, more particularly, to a single electronic module which processes images from multiple image capture devices, such as CMOS video cameras, mounted throughout the interior and/or exterior of a vehicle, such as an automobile.
BACKGROUND THE INVENTION
[0003] It is known to use multiple video cameras on a vehicle to capture images both interior to the vehicle and exterior to the vehicle. It is also known to process the image outputs of such cameras by a variety of controls in order to display said images to a driver or another occupant of the vehicle, or to utilize the output of a camera in order to generate a control signal for a vehicular accessory, such as a headlamp or windshield wiper. As the number and complexity of camera-based accessories and features grows in a vehicle, there is a need to economically and efficiently process the multiple outputs from a plurality of camera and other sensors in order to perform a plurality of image displays and control functions.
SUMMARY OF THE INVENTION
[0004] The present invention is directed to a Video Processor Module (VPM) that is adapted to accept input from several vehicular cameras and optionally from other non-video devices and sensors in or on the vehicle and to process the image outputs therefrom in order to provide a variety of functions and controls. The VPM is preferably further adapted to interface with other vehicle modules via interfaces to the vehicle communication buses, such as via a CAN bus and/or a LIN bus.
[0005] A vehicle-based video processor module for a video system of a vehicle, according to an aspect of the invention, includes a video processor circuit, a plurality of electronic sensor interfaces that are operable to receive image output data from a plurality of imaging devices and at least one electronic vehicle interface that is operable to communicate with a vehicle communication bus. The video processor circuit is operable to process the image output data from the plurality of imaging devices into a single database in a standard format.
[0006] A vehicle-based video processor module for a video system of a vehicle, according to an aspect of the invention, includes a video processor circuit, a plurality of electronic sensor interfaces that are operable to receive image output data from a plurality of imaging devices and at least one electronic vehicle interface that is operable to communicate with a vehicle communication bus. The video processor circuit is operable to process the image output data from the plurality of imaging devices and to enhance the image output data.
[0007] These and other objects, advantages and features of this invention will become apparent upon review of the following specification in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a top plan view of a vehicle outfitted with a vehicular video system, according to the invention; and
[0009] FIG. 2 is a block diagram of a video processor module, according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0010] Referring now to the drawings and the illustrative embodiments depicted therein, a vehicle 10 is illustrated in FIG. 1 having a vehicular video system 12 , according to the invention. Vehicular video system 12 includes video processor module (VPM) 14 , which receives input from a plurality of sensors, generally shown at 16 . VPM 14 processes the output data from the plurality of devices and enhances the image output data. Sensors 16 may be imaging devices, such as vehicular cameras, as well as non-imaging devices. An example of a mix of sensors 16 that may be used in vehicular video system 12 includes imaging sensors, forward-facing imaging sensors, rearward-facing imaging sensors, left-side-facing imaging sensors, right-side-imaging sensors, inward-facing cabin-imaging sensors, and the like. Non-video sensors may include a near infrared sensor, a far infrared sensor, a radar sensor such as a Doppler radar sensor, a sonar sensor, a thermal sensor, a night vision sensor such as a multi-pixel bolometer and any other sensors which establish the presence, distance to, position and/or speed of an object. A Doppler radar sensor or side-facing camera may be mounted at an exterior mirror assembly. A forward-facing camera may be mounted at an interior mirror assembly of the vehicle that performs a headlamp control and/or windshield wiper control function. A side lane blind spot and/or lane change system may be provided and the VPM may be adapted to accept data from a variety of other non-video sensors to enhance performance in all visibility situations, such as when driving in fog or other low visibility conditions.
[0011] Video processor module 14 includes a video processor circuit 18 and a plurality of electronic sensor interfaces 20 for receiving data from a plurality of sensors 16 . In the embodiment illustrated in FIG. 2 , electronic interfaces 20 are illustrated as receiving image data output respectively from right-hand-facing and left-hand-facing side cameras, a front-facing camera and a rear-facing camera. The image data may be transmitted across a robust transmission means, such as a fiber-optic cable or a high-density wireless link, or the like. However, electronic interfaces 20 are capable of receiving data from non-imaging sensors as well. Electronic interfaces 20 may be utilized, J1394 Firewire protocol, NTSC protocol, or other standard protocol. Video processor module 14 includes at least one electronic vehicle interface 22 which is operative to interface with a vehicle bus, such as a CAN bus, a LIN bus, or the like.
[0012] Video processor circuit 18 includes a core 26 to exchange data with electronic sensor interfaces 20 , and a core 28 to exchange data with electronic vehicle interfaces 22 . A memory device 24 stores various data such as settings. Video processor circuit 18 includes a camera selection and advanced camera control section 30 for controlling the individual sensor devices and for integrating data from the plurality of sensors, such as by fusing or combining image data from multiple imaging sensors and data from non-imaging sensors. This combined or fused data is preprocessed into a single database in a standard format. Video processor circuit 18 further includes an object-tracking section 32 for tracking objects that are identified and classified by an object classification section 34 . Video processor circuit 18 further includes a display section 36 which generates on-screen display signals and a diagnostic section 35 for performing diagnostics.
[0013] Having described the components of vehicular video system 12 and their operation, examples of various functions that can be supported with this vehicular video system will be set forth. One set of functions includes features for viewing of a displayed image. Video processor module 14 may be capable of merging of images from a plurality of imaging sensors 16 to provide a panoramic view, which exceeds the field of view of a single camera or allows the image to “wrap” around the vehicle. Video processor module 14 may be further capable of electronic elimination of distortions created by wide-angle lenses used with sensors 16 . Video processor module 14 may be capable of superimposing graphics onto a displayed image to provide additional information to the observer.
[0014] Another set of functions includes features for sensing using an electronic image. Video processor module 14 may be programmed to be capable of detection with object position, speed and classification to support one or more of the following features:
Blind spot detection Lane change aid Adaptive speed control Reverse aid warning Advanced crash warning
Video processor module 14 may be programmed to be capable of detecting the location of a lane on a road in conjunction with an imaging sensor 16 . This capability can support a lane departure-warning feature or autonomous vehicle control. Video processor module 14 may use imaging sensors to establish ambient lighting and detect other vehicles for automatic control of the headlamps (on/off) and high/low beams. Video processor module 14 may have the capability to use imaging sensors to establish ambient lighting and vehicle headlamps for automatic control of electrochromic mirrors. Video processor module 14 may have the capability to detect the presence, position and size of occupants inside the vehicle. Video processor module 14 may have the capability to stabilize an image for viewing or use in sensing algorithms. It should be understood that the listed features and functions are illustrative only. Which of the particular ones that are used for a particular vehicular application may differ from those used for other vehicular applications. Additionally, other features and functions may be identified for video processor module 14 by the skilled artisan.
[0020] VPM 14 can be utilized in a variety of applications such as disclosed in commonly assigned U.S. Pat. Nos. 5,670,935; 5,949,331; 6,222,447; 6,201,642; 6,097,023; 5,715,093; 5,796,094 and 5,877,897 and commonly assigned patent applications, Ser. No. 09/793,002 filed Feb. 26, 2001, now U.S. Pat. No. 6,690,268, Ser. No. 09/372,915, filed Aug. 12, 1999, now U.S. Pat. No. 6,396,397, Ser. No. 09/767,939, filed Jan. 23, 2001, now U.S. Pat. No. 6,590,719, Ser. No. 09/776,625, filed Feb. 5, 2001, now U.S. Pat. No. 6,611,202, Ser. No. 09/799,993, filed Mar. 6, 2001, now U.S. Pat. No. 6,538,827, Ser. No. 09/493,522, filed Jan. 28, 2000, now U.S. Pat. No. 6,426,492, Ser. No. 09/199,907, filed Nov. 25, 1998, now U.S. Pat. No. 6,717,610, Ser. No. 08/952,026, filed Nov. 19, 1997,now U.S. Pat. No. 6,498,620, and Ser. No. 09/227,344, filed Jan. 8, 1999, now U.S. Pat. No. 6,302,545, International Publication No. WO 96/38319, published Dec. 5, 1996, and International Publication No. WO 99/23828, published May 14, 1999, the disclosures of which are collectively incorporated herein by reference.
[0021] For example, VPM 14 can be utilized in a vehicle equipped with a side object detection system utilizing stereoscopic imaging from cameras located in the driver-side exterior mirror assembly and/or in the passenger-side exterior mirror assembly, such as is described in commonly assigned patent application Ser. No. 09/372,915, filed Aug. 12, 1999, now U.S. Pat. No. 6,396,397, the disclosure of which is hereby incorporated herein by reference, and further equipped with a CMOS camera-based headlamp controller as disclosed in commonly assigned U.S. Pat. Nos. 5,796,094 and 6,097,023, the disclosures of which are hereby incorporated herein by reference, and with the various image outputs being processed by the VPM. In this regard, should the vehicle be equipped with high intensity discharge (HID)/gas discharge headlamps (as known in the automotive lighting art), then the VPM can receive the output signal from a forward-facing CMOS camera (preferably mounted at or in the interior rearview mirror assembly and viewing oncoming headlights of approaching vehicles through the front windshield of the vehicle) and the VPM can control the intensity and/or direction of the light beam output from the HID headlamps as a function of the light level of the oncoming approaching headlamps as detected by the interior rearview mirror located forward-facing multipixel CMOS camera-on-a-chip light detector. Preferably, the intensity of the light beam output by the vehicle's HID lamps is inversely proportional to the intensity of the detected oncoming headlamps and, most preferably, the intensity of the HID headlamps is continuously variable inversely proportional to the intensity of the oncoming headlight intensity of approaching vehicles as detected by the forward-facing CMOS camera.
[0022] Further, and preferably, the vehicle may be equipped with a mobile cellular phone that is docked into a cell phone cradle system (such as in the CellPort 3000 system available from Cellport Systems Inc. of Boulder, CO) to allow a driver to conduct a hands-free telephone call when driving, and to provide the driver the option of undocking the cellular phone as desired in order to use the cellular phone, for example, when the driver departs the vehicle. The cell phone cradle system can include a sound-processing system (preferably including a microphone or microphone array, and such as is disclosed in commonly assigned patent application Ser. No. 09/466,010, filed Dec. 17, 1999, now U.S. Pat. No. 6,420,975, the disclosure of which is hereby incorporated herein by reference, and other accessories, and with the cell cradle providing outputs at least partially processed by the VPM.
[0023] The vehicle may also be equipped with a navigational system, such as a global positioning system, and with controls and/or functions of said navigational system being at least partially processed by VPM 14 . For a vehicle equipped with a GPS system and with a cell phone cradle (such as the CellPort 3000 system), a control input can be provided in the interior of the vehicle (such as at or on the interior mirror assembly) and/or a voice command control system can be provided whereby when the control input and/or voice command is actuated, a call is initiated to an external service (such as an emergency service of a concierge service or an information service) located remote from the vehicle and wherein the location of the vehicle (as generated by the vehicular navigational system) is automatically transmitted to the external service so that the external service can know the location of the vehicle and so provide assistance, advice and/or directions, and the like, to the driver of that vehicle. Such communication of geographic positional data can be transmitted by telecommunication via a phone network (such as Sprint or MCI or ATT, or the like) in a voice-over-data format allowing the driver to have a conversation with the service provider (and/or with another party) concurrent with the transmission of the vehicle location information to the service provider via telephonic linkage via the docked cell phone (or, optionally, via a BLUETOOTH or similar short-range RF wireless link between a cellular phone in, for example, the pocket of a driver and a cell phone linking/telecommunication/telematic station located, for example, at an interior rearview mirror assembly of the vehicle or in a dashboard or console area of the vehicle) to the external service provider. Preferably, at least some of such processing is handled by VPM 14 and, in particular, when videoconferencing is used.
[0024] The present invention can be used in a lane change aid system such as disclosed in a commonly assigned provisional patent application Ser. No. 60/309,022 filed Jul. 31, 2001, and a utility patent application filed concurrently herewith by Schofield for an AUTOMOTIVE LANE CHANGE AID, now U.S. Pat. No. 6,882,287, the disclosures of which are hereby incorporated herein by reference.
[0025] Also, a night vision system camera (such as an infrared detecting microbolometer night vision camera or a CMOS/near-IR detecting camera used in conjunction with a near-IR laser source for illumination forward of the vehicle) and an intelligent headlamp controller (such as a forward-facing CMOS video camera that automatically detects approaching vehicles and that dims the headlights of the host vehicle in response) can have their outputs combined/fused in accordance with the present invention to identify objects hazardous to the driver, such as a deer crossing the road ahead of the vehicle as the vehicle travels down a dark road at night. The control can, in response, automatically activate one or both existing headlamps, for example, to flash them or to move from a low-beam state to a high-beam state or to activate an additional headlamp or fog lamp or to adjust headlamps to high beam so that the object may be illuminated for the driver. Current night vision systems may either provide too much information for the driver to usefully assimilate or may distract him/her from attention to the road. The above combination achieved via the fusion system of the present invention allows use of the night vision system/intelligent headlamp controller to automatically provide extra forward illumination at the time required for the driver to take action to avoid a problem, which is the real intent behind the night vision system in the first place. The fusion of these inputs into a single processor achieves optimized nighttime driving safety. Note that a single forward-facing camera can perform both the night vision and intelligent headlamp control functions.
[0026] VPM 14 may receive both wired inputs and wireless inputs. For example, a restricted-range RF wireless communication device such as a BLUETOOTH device (housed, for example within an inside mirror or housed elsewhere in the interior cabin such as in an overhead console or a facia/instrumentation panel) can be used as a convenient channel location for the programming or reprogramming of various types of radio-frequency (RF) devices in a vehicle and/or to facilitate the use of RF as a means to program or reprogram non-RF devices to provide drivers with a more complete personalization of a vehicle (e.g., trainable garage door open, memory seat/mirror position, outside mirror position, etc.). This can be used in, for example, rental cars where an RF signal can be provided (such as via an RF transmitter located in the interior mirror assembly or in a windshield electronic accessory module) from a personal display assistant device (PDA) such as a PalmPilot® PDA and thus provide a driver with immediate personalization to include temperature/climate control, radio setting, exterior mirror reflector position and other preferences.
[0027] In accordance with U.S. Pat. Nos. 5,949,331 and 6,222,447, incorporated by reference above, a display system of the equipped vehicle displays a synthesized image that visually informs the driver of what is occurring in the area surrounding the equipped vehicle. The displayed image is synthesized from the camera outputs and, preferably, approximates a substantially seamless panoramic view as would be viewed by a single virtual camera located exterior the equipped vehicle.
[0028] Changes and modifications in the specifically described embodiments can be carried out without departing from the principles of the invention, which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents. | A vehicular driving assist system includes a data processor module that receives and processes image data provided by a plurality of video sensors and sensor data provided by a plurality of non-video sensors. The video sensors include at least five cameras disposed at respective locations of the vehicle and having respective fields of view exterior the vehicle. The data processor module communicates with other vehicle systems via a vehicle bus of the vehicle. Received image data and received sensor data are processed at the data processor module for at least one of (i) object tracking of objects present exterior of the vehicle, (ii) object identification of objects present exterior of the vehicle and (iii) object classification of objects present exterior of the vehicle. Responsive at least in part to processing of image data and sensor data at the data processor module, a driving assistance system of the vehicle is controlled. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present invention claims the benefit of Provisional Patent Application No. 60/049,928, filed Jun. 18, 1997 entitled "DATA SERIALIZATION", which is incorporated herein by reference for all purposes.
BACKGROUND OF THE INVENTION
The present invention relates generally to data storage systems and more particularly relates to tape drive emulation (TDE) systems.
Many data processing systems utilize tape drives for storage of data. Channel interfaces and commands generated by a data source to control the transfer of data from a host computer to a tape drive are well-known in the art and will not be described in detail here. One example of an operating system for managing data transfer between a host computer and a tape drive is the MVS system manufactured by the IBM Corporation.
Write and read operations of a tape drive are, of course, all sequential from the viewpoint of the using host or hosts. Thus, even though I/O may be done over multiple ESCON links (or over such other channel path types as BMC or SCSI), all leading to the same drive, commands for the drive are issued and active on only one link or path at a time. Ending status for each command must reach the channel which issued the command before it or another channel will issue a subsequent command.
Within a tape subsystem, a drive commonly connects to two tape controllers and each controller connects to more than one host channel or ESCON link. Within each tape controller, a data buffer set and a data formatter, including compression circuits, are shared by processes routing data to and from multiple drives and routing data to and from multiple host connections. Further, the two controllers connecting to a drive often have connections also to each other's data buffer and formatter.
Channel connections (ESCON or other) may link a controller to more than one host to permit sharing of tape drives, though not to allow multiple computers to do I/O to a given tape during a single period when the tape is mounted on a drive. A reliable scheme of reservations is needed to serialize the use of such shared drives among the hosts.
In the course of writing a single tape, more than one of the many paths available through the subsystem might be used. Multiple data blocks on their way to a tape may arrive on different paths and be buffered in controllers at one time. Even though the blocks leave the host in a wanted sequence, ensuring that they reach the tape in the same sequence requires a reliable system of data serialization rules and mechanisms.
Drive Serialization
In many tape subsystems, drive serialization is accomplished by a convention under which hosts first declare "path groups" to identify sets of host-to-controller-to-drive paths which are eligible to be used concurrently by a single host for I/O to a single drive. Data to/from a drive may move across paths in such a group in any pattern of alternating choice of path. "Alternation" means the paths may be used "concurrently" but not "simultaneously," since I/O is always sequential--one command at a time.
For a host to actually use a drive, the drive must be "assigned" to the path group created for that host's use of the drive. Assignment has the quality of a mutual exclusion lock or "mutex" in that a drive can only be assigned to paths of one group at a time. Thus, path grouping and assignment achieves drive serialization. Assignment and path grouping are accomplished by a host through a set of special channel commands defined for the purpose. MVS and some other host operating systems follow this drive serialization convention.
In a tape drive emulation system, the data output by the host is not actually written to a tape drive and data input by the host is not actually read from a tape drive. In one type of TDE system the data is stored on staging disks.
Data Serialization
The basic unit of data processed by channel commands is a "block." Prior to storage, blocks are usually compressed and "packetized," with each packet including compressed data, a header, and a trailer. As is well-known, the header and trailer include control information, information about the data block, and error checking information.
In a TDE system several packets may be in processing at a given time. Thus, a reliable system for maintaining the sequential ordering inherent in tape-formatted data must be developed for a TDE system.
SUMMARY OF THE INVENTION
According to one aspect of the invention, serialization of packets stored in an extent buffer is assured by associating block ID numbers with blocks received from a host. The order of the block ID numbers is the same as the order in which the blocks are received.
According to another aspect of the invention, a locking system allows only one channel interface at a time to access ownership fields in data structures. These ownership fields are used as a MUTEX to prevent other channel interfaces from obtaining a block ID number from the data structure or incrementing a block ID number until the owning channel interface completes executing its command.
According to another aspect of the invention, the block ID number of the data to be processed next is maintained in a status field of a control data structure. Channel interfaces transfer a block when the block ID of the block to be transferred is equal to the block ID number indicated by the status field.
According to another aspect of the invention, data synchronization can be executed when the block ID which could be assigned to a next block coming from the host is equal to the block ID stored in said status field.
Other features and advantages of the invention will be apparent in view of the following detailed description and appended drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a preferred embodiment of the invention;
FIG. 2 is a schematic diagram depicting the data paths of the system depicted in FIG. 1;
FIG. 3 is a schematic diagram of an ANSI X3.224-1994 packet;
FIG. 4 is a flow chart depicting the steps performed to order block reads;
FIG. 5 is a flow chart depicting steps performed to assign block IDs for a write command;
FIG. 6 is a flow chart depicting steps performed to order packets in extent buffers; and
FIG. 7 is a flow chart depicting the steps performed to execute a synchronize command.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment will now be described with reference to the figures, where like or similar elements are designated with the same reference numerals throughout the several views. FIG. 1 is a high level block diagram of a part of a tape drive emulation system 10 utilizing an embodiment of the present invention.
A plurality of channel interfaces (CIFs) 12 are coupled to host I/O channels (not shown) to transfer data between the host and the TDE system 10.
Each CIF 12 includes a host interface 14, an embedded controller 16, a data formatter 18 for performing data compression and other functions, a buffer memory 20, an SBUS interface 22, and an internal bus 24. In the preferred embodiment the embedded processor 16 is a model i960 manufactured by Intel Corporation.
A main controller 30 includes a main processor 32, main memory 34, an SBUS interface 36, and an internal bus 38. In the preferred embodiment, main processor 32 is a SPARC computer manufactured by Sun Microsystems Incorporated. The CIFs 12 and main controller 30 are coupled by a system bus 40.
The tape drive emulation (TDE) system 10 stores host data on "virtual tape drives." In one preferred embodiment the data is actually stored on staging disks 60. Because TDE system 10 must interact with the host as if the data were actually stored on tape drives, a data structure called a virtual tape drive (VTD) is maintained in main memory 34 for each virtual tape drive. The VTD contains all information about the state of the associated virtual tape drive. Various fields in the VTD will be described in detail below.
Control tables used by TDE system 10 to store the current state of path grouping and assignment are kept in shared portions of (SPARC) main memory 34. Any embedded (i960) processor 16 which receives a command from a channel addressing a virtual tape drive consults the shared tables to confirm that the path involved is authorized for execution of the command, before proceeding with execution. Any i960 may also alter the tables, on command from an attached host, if the alteration is allowed by the path control convention.
Because i960's 16 share the path tables, both for reference and update, and because all their table uses need tables in a consistent state, a reliable system of "control-data serialization" must be used.
The CIFs 12 are implemented on dual SBus base boards (DSBs) in a preferred embodiment. A feature of the DSB hardware answers this need for control-data serialization. A set of request/grant lines form a LOCK bus 50 in the backplane, linking circuits on all DSB's, and functioning as a mutex on all SPARC memory shared by the i960s. The facility grants "control" exclusively to one i960 at a time. An i960 can only read or change those items in shared (SPARC) memory needing protection if it has and maintains control of this hardware LOCK. Consistency of the shared items is thus assured.
The path control tables governing drive serialization are always protected by the LOCK. An "ownership" field in the VTD (meaning here the shared-memory structure of control data items characterizing the state of a virtual tape drive) is also only tested or changed under protection of the LOCK.
Data Serialization
The data paths of the embodiment depicted in FIG. 1 are shown in FIG. 2. In the preferred embodiment, data is stored on staging disks 60. The staging disk space is treated as collections, called regions, of fixed-size space units called extents.
Referring to FIG. 2, packets are formed in the CIFs and stored in extent buffer 74. In a preferred embodiment, the packets are packetized based on the model of data packets of the 3480/IDRC or 3490 (see ANSI X3.224-1994, X3.225-1994). The packet format is depicted in FIG. 3.
The CIF buffers 70 and 72 are regions of the channel interface memory 20. The extent buffer is a region of main memory 34. The size of the extent buffer is the same as the fixed-space unit on the disk to facilitate efficient transfer between the staging disks 60 and extent buffer 74.
In one write mode of operation, entire packets are transferred from the CIFs 12 to the extent buffer 74. When there is not room in the extent buffer for another entire packet the remaining unused part of the extent buffer is packed with ones and then the contents of the buffer are written to a fixed-sized region on the staging disk.
Each packet formed in a CIF 12 is assigned a block ID which is included in the packet. As described below, these block ID's are utilized to assure data serialization.
Three aspects of data serialization are crucial: 1) block ID's must be assigned to data blocks in the sequence of their arrival from a host, 2) the blocks must be delivered to a reading (or spacing) host in block ID order, and 3) packets (containing the numbered data blocks) and virtual tape marks must be loaded into extent buffers in the shared memory according to block ID order.
The ordering of block reads will now be described with reference to the flow chart of FIG. 4.
Each i960 CIF processor 16 executes an instance of a program called TDE-embedded.
When a READ channel command reaches an i960 from a host, that is, reaches an instance of TDE-embedded which is called thisTDE, thisTDE secures the LOCK before beginning execution of the command. The LOCK is secured by asserting a request on the REQ line of the LOCK bus 50 to acquire the LOCK. If the BUSY line is not asserted, then thisTDE acquires the LOCK and has access to ownership fields of the VTD data structure associated with the virtual drive designated by the received command. Possession of the LOCK continues until thisTDE removes the request from the REQ line.
The VTD data structure includes various status elements used to form a mutual exclusion lock (MUTEX) for the VTD. After securing the LOCK, thisTDE queries a status element called VTD -- BUSY in the VTD status attribute. VTD -- BUSY serves as a mutex for control of a VTD. If VTD -- BUSY is set, thisTDE releases the lock and rejects the channel command.
If VTD -- BUSY is not set, thisTDE sets VTD -- BUSY and thereby secures the VTD against execution of any command by any other i960. Now "owning" the VTD, thisTDE releases the LOCK.
With exclusive control of the VTD now assured, thisTDE finds the proper next block ID in a field of the VTD called packetID, retrieves the block ID, and assigns it to any data block or tape mark incoming from the channel.
Next, a VTD -- Data -- Buffered status field is checked. If it is not set the steps described immediately below are performed. The steps performed if it is set will be described in connection with executing a SYNCHRONIZE command.
thisTDE executes the READ command, holding the VTD in the VTD -- BUSY state all the while.
When all data for the command has moved between the host and the i960 local buffer and ending status has been prepared but not delivered, thisTDE increments or decrements the packetID in the VTD (or not, in some cases of command execution error) in preparation for subsequent commands. thisTDE then releases the VTD by clearing VTD -- BUSY from status. LOCK protection is not needed during this release step. Finally, thisTDE returns ending status to the host.
The steps for assignment of block IDs are depicted in FIG. 5. The first several steps are identical to the READ command. After the LOCK is released a packetID is assigned the BlockID.
A field of the VTD called sbusPacket contains the block ID which should appear in the next packet to be loaded into an extent buffer.
The value of the block ID in sbusPacket is initialized under protection of the LOCK by whichever i960 (thisTDE) executes the first of any sequence of writes. thisTDE identifies such a first write by testing a status element called VTD -- DATA -- BUFFERED. The appearance of VTD -- DATA -- BUFFERED being set in status means that there is unsynchronized data, either in extent buffers or in i960 local buffers. Thus, if VTD -- DATA -- BUFFERED is set, the received command is not the first of a sequence of writes. Thus, the block ID in sbusPacket has already been initialized, and some sequence of writes has already begun.
If VTD -- DATA -- BUFFERED is not set, then thisTDE initializes the block ID in sbusPacket and sets the VTD -- DATA -- BUFFERED status element.
Once VTD -- Data -- Buffered is set, the WRITE command is tested to determine whether it is a Write-Tape-Mark command. If it is not, then the steps described immediately below are performed. The steps performed if it is will be described in connection with executing a SYNCHRONIZE command.
When all data for the command has moved between the host and the i960 local buffer and ending status has been prepared but not delivered, thisTDE increments or decrements the packetID in the VTD (or not, in some cases of command execution error) in preparation for subsequent commands. thisTDE then releases the VTD by clearing VTD -- BUSY from status. LOCK protection is not needed during this release step. Finally, thisTDE returns ending status to the host.
The ordering of packets in extent buffers will now be described with reference to FIG. 6. When thisTDE holds a packet in its local buffer with a block ID matching the block ID in sbuspacket, it is assured that no other i960 will load a packet into an extent buffer because a packet can be written to the extent buffer only if its block ID value matches the value of the block ID in sbuspacket. Therefore, the match of packet id's constitutes a mutex or lock on the extent buffers and on all VTD control variables relating to extent buffer management. The TDE instance which, in beginning a new series of writes, initializes the block ID in sbusPacket to match the block ID of the block it is about to receive from a host, thereby locks the extent buffer until its packet reaches the shared memory.
When thisTDE completes transfer of a packet into an extent buffer (shared memory), it adjusts a pointer indicating where in the extent buffer the next block should be stored and increments the block ID in sbusPacket, thereby relinquishing its implied lock on the extent buffer and related resources. No LOCK protection is needed for this release.
As is known in the art, data is synchronized when all host data output to a data storage unit is securely stored on non-volatile media. In the context of the system depicted in FIGS. 1 and 2, a data synchronization command causes all data stored in CIF buffers 70 and 72 and extent buffers 74 be written to the staging disks 60.
The execution of a SYNCHRONIZE command will now be described with reference to the flow chart of FIG. 7. When a command is received that provokes synchronization (write tape mark, BSB, Synchronize, etc.), the i960 executing the command waits until the block ID in sbusPacket and packetID are the same, indicating reliably that no data remains in an i960 local buffer since the next packet to be stored is also the next one to be sent by a host.
Referring back to FIG. 4, PacketID=Sbus -- Packet (i.e., the value of the Packet ID to be assigned to any block newly arriving from the host when the synchronize command arises equals the value of the packet ID sbuspacket) may occur for a back-space operation. In this case, a synchronize command is executed. In FIG. 5, PacketID=Sbus -- Packet may occur for a write-tape-mark command, in which case a synchronize command is executed.
Referring back to FIG. 7, generally, for a synchronize command, data is synchronized when PacketID=Sbus -- Packet. The essence of synchronization is that all unwritten but buffered data must be written to non-volatile media and records identifying storage locations and other status altered by newly added data must be made non-volatile.
Thus, the problem of serialization of data loading into extent buffers is solved by the serialization of block ID assignments, which in turn has the LOCK as its primary underpinning.
The invention has now been described with reference to the preferred embodiments. Alternatives and substitutions will now be apparent to persons of skill in the art. Accordingly, it is not intended to limit the invention, except as provided by the appended claims. | A system for serializing and synchronizing data stored in a tape drive emulation system utilizes a physical lock system and control data MUTEXes to assure serialization. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates to a method and system that balances the amount of data being transmitted over cellular networks which will decrease the amount of bandwidth required to perform data transmissions and will optimize the average time to transmit large date files. In particular, this invention relates to a method and system for optimizing the transfer of large files to a receiving device by balancing the transmission loads of nodes on a wireless network such that transmission times for file transfers remains at an optimal average across all nodes on the network.
BACKGROUND OF THE INVENTION
[0002] Cellular telephones are an integral part of society today. A substantial number of people throughout the world have and use cellular telephones. For many people, the cellular telephone is their primary means of communicating, and of receiving and sending information. Individuals use cellular telephones for personal business and also in the work environment to conduct business matters. Cellular telephones have become a convenient means to take pictures, record events and save and retain information. As technological advancements with regards to the cellular telephone occur, more features are available on the cellular telephone. People easily find new uses for the cellular telephone based on the new features. Many consumers pre-order the latest cellular telephone devices and often, there are long lines of consumer waiting to be the first to have the new devices with the latest technology.
[0003] Currently, with all of the new technical developments and the expanded uses for small mobile electronic devices, the cellular telephone industry is going through a major transition. Most of the original usage of cellular phones was voice usage. People used cellular phones to conduct verbal communication. A main type of cellular phone was the “feature” phone. These earlier phones did not have big screens and many of the current features and they were used primarily to make telephone calls. Today, there is the ‘smart’ phone. The current cellular phone devices have many more features than original cellular phones. As a result, people are finding more uses for these phones. Further, where the primary use of original cellular phones was voice, today people are using their cellular phone devices to transmit data (i.e. text and images). In fact, usage of cellular phones is becoming more to transmit data than voice. This shift in usage from voice to data is creating a challenging situation for the cellular phone network providers. The original design of cellular networks did not anticipate the increasing transmission of data. The increase in data traffic places a strain on the cellular network operations. A conventional cellular network configuration 100 shown in FIG. 1 has antennas, radios and logic 102 . The area 104 of each antenna (tower) device 102 is referred to the ‘Node’. The cellular telephone devices 106 communicate with and through the cellular network through the antennas in the specific Node areas. Each node area also has a server computing device 108 . In the cellular network 100 , these server devices 108 communicate with a Core Radio Node Controller (RNC) 110 . One RNC 110 may have connected to it a hundred Nodes 104 . The connection between the Node B and RNC can be through a microwave link 112 . Next the RNC can further connect to the core network. The core network can also have several RNCs connected to it. Because these communication links 110 between the RNC and the nodes and even a core network are microwave links, there is a limited amount of bandwidth available to transmit information across these microwave links. These communication links have plenty of bandwidth to transmit voice communications. However, with the increased use of data-driven applications such as browsing the web, texting and watching videos via their cellular phones, the bandwidth on these microwave links is approaching the capacity of use.
[0004] The cellular telephone design and the cellular telephone protocols are designed to enable a cell phone user to roam through a cellular network. Referring to FIG. 2 , a cellular network 200 is comprised of several little cells 202 . A user can transparently move from one cell to another cell. The user is not disturbed as they move between cells. In some locations, such as metropolitan areas, a cellular phone user can be in one location and can switch cell sites every few seconds and not notice. The cellular network addresses all of the switching from one cell to another cell for the user.
[0005] When a user is on a wireless network, whether it is a cellular telephone data network or WIFI network, many times towers 102 and access points are not being utilized to their full potential. Due to this fact, tower wireless networks remain basically unintelligent. Current technologies allow users to seamlessly travel from one access point to another without noticing any interruptions in service activities. However, with regards to downloading large data files interruptions can occur when moving from one access point (antenna tower) to another access point.
[0006] U.S. Pat. No. 7,697,508 to Hernandez-Mondragon, et al. describes a system for communication between a mobile node and a communications network for use with a communications network having one or more communications network nodes. This invention defines a foreign agent and communicates with the mobile node in a predefined region. The system includes a ghost-foreign agent that advertises a foreign agent so that the mobile node is aware of the foreign agent when the mobile node is located outside the predefined region. The system further includes a ghost-mobile node that signals the foreign agent in response to the foreign agent advertising and based upon a predicted future state of the mobile node.
[0007] U.S. Patent Application Publication number 20100323715 describes technologies that are generally related to predicting future mobile device locations and using the predictive information to optimize mobile communications service parameters. Mobile device locations may be predicted using real-time device location information, destination information, and location history. Predicted location information for a given device, and possibly other devices as well, may be used to adjust mobile communications service parameters such as handoffs, channel assignment, multipath fading response parameters, data rates, transmission modes, opportunistic scheduling parameters, location-based services, and location update rates.
[0008] Although these technologies do enhance the communications of electronic devices, there remains a need for a more seamless communication system that can optimize large file transfers while moving through nodes on a wireless network.
SUMMARY OF THE INVENTION
[0009] The present invention addresses bandwidth capacity problems when transferring large files while a user is moving across nodes of a wireless network. This invention comprises a method of analyzing the bandwidth capacity of wireless nodes, the moving patterns of end users inside a wireless node zone to predict when and where the user will transfer from one wireless node to another wireless node. The method of the invention determines the size of the data to be downloaded, the download speed, the amount of time and the amount of bandwidth required to download data to a wireless device.
[0010] The present invention will determine the capacity of the current node of the wireless device receiving the data and will determine if that wireless device is moving to a different node in the network. In practice, user movement is detected and a pattern of movement is determined. From this determination there is a prediction or projection of the path of the user. Based on the movement of the user, size of the file that is being transferred and the transfer rate, the present invention can predict the amount of a file that will be transferred to a user while the user is in a certain node area. The present invention can also determine the download speed of the transfer based on the capacity of the current tower of the user device. Based on the size of the file being download, the capacity of the current node receiving the downloaded file and the capacity of the predicted future node of the device, the present invention can adjust downward the download speed of the file in the current node and the adjust upward the download speed of the file once the user device has moved to the next node which has more available download capacity. By adjusting the download speeds of the file being transferred, the average download time for the file is the same. However, because of the reduced download speed in the initial node, the average download speed is that node remains at an optimal level.
DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is an illustration of a cellular network configuration containing a network core, radio node controller (RNC) and multiple Node B area cell sites.
[0012] FIG. 2 is a display of several Node B cell sites comprising a network of adjacent cellular sites, each cell site having an antenna, radio and logic.
[0013] FIG. 3 is an illustration of a cellular network configuration containing a network core, radio node controller (RNC) and multiple Node B cell sites with different load demands.
[0014] FIG. 4 is an illustration of a cellular network configuration showing movement of cellular devices between node areas.
[0015] FIG. 5 is a flow diagram of the steps in a general implementation of the method of the present invention.
[0016] FIG. 6 is a flow diagram of the steps in an alternate implementation of the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The method and system of the present invention provide a means to provide seamless transfer of large files across network nodes with optimal bandwidth usage by balancing the download functions of network nodes. The objective of the present invention is accomplished by distributing the download functions of devices moving between nodes and thereby reducing load capacity of nodes having heavy usage at a particular time. Download speeds for devices moving between nodes will be reduced while the device is in a heavy capacity use node and increased when the device moves to a node having a lower use capacity. This load balancing process occurs by:
1) determining the size of a file to be transferred to a user; 2) predicting the path of the user; 3) determining the current load at each node in the network; and 4) determining whether load balancing can occur based on the movement of the user and the current load of nodes in user's predicted path.
When the determination is that load balancing can occur, the download speed of the file to the user device is reduced when the user is in a load capacity node area. Reducing the download speed of this user enables the download speed of another user in that same node area to increase. When the user moves to the node area with less use, the download speed of the file to the user will increase such that the total time to download a file is optimized. The increased download speed in the second node compensates for the slower download speed in the first node such that the total download is optimal.
[0022] FIG. 3 is an illustration of a cellular network configuration containing a network core, radio node controller (RNC) and multiple Node B cell sites with different load demands. This configuration shows three node areas with different use loads. As shown, Area 2 currently has five downloads from five devices 306 , while Area 1 and Area 3 each only have two current downloads. As a result of the different load usages, downloads in Area 2 require more bandwidth and will generally download at slower speeds because of the greater demand. Each Area generally has an average download speed. When the use increases, the average speed can reduce for each download to simultaneously download data to each device.
[0023] FIG. 4 illustrates a cellular network configuration when devices in Area 2 are moving though that area and possibility into other area. As shown, when devices 306 from Area 2 move into Area 1 and Area 3 the download times for devices in Area 2 can increase because of the reduced capacity in Area 2.
[0024] Referring to FIG. 5 , In the method of the invention, in step 502 , there is a request for data from a mobile device 306 . Once a request is received step 504 identifies and locates the requested data. The Network Core 102 and RNC 110 are components that can perform this function. In step 506 , the invention begins downloading the requested data to the requesting device via the node area of the requesting device. After the initiation of the downloading process in step 506 , step 508 begins to determine the current load volume at that node tower. As part of the determination of the volume at the particular node area, step 510 determines if the current volume of use at a node has exceeded a threshold capacity for that node. For example, a threshold capacity could be 90 percent use of the capacity. Once the capacity reaches 90 percent, the node has reached the threshold capacity. This threshold capacity is an arbitrary number that can be set for any particular system or any particular node area in a system. This threshold number serves as one of the markers to initiate load balancing activities of the present invention. If the determination in step 510 is that the capacity is below the threshold capacity, then the process goes into a monitoring state in step 512 .
[0025] Referring back to step 510 , if the determination is that the use capacity at the specific node has reached the threshold capacity, then the process moves to step 514 which attempts to detect movement of devices receiving data at the specific node area. In this step, the method can monitor each device in the specific area that is receiving data and determine the size of the data that the device is receiving and the amount of data that the device has yet to receive. The objective at this point is to determine which devices may be moving to other node areas that are below their threshold capacity. Devices receiving data that are moving to other nodes that are below their threshold capacity may be candidates for load balancing. When step 514 detects the movement of a device receiving data, step 516 projects the path of future movement for that device. As part of the process of projecting the path of future movement of the device, step 518 determines whether the future movement of the device will take the device out of the current node area and into a different node area. If the determination is that the projected movement of the device will not take the device out of the current node area, then that device is not a likely candidate for the load balancing of the present invention. In this event, the method would return to the monitoring step 512 .
[0026] Referring to step 518 , when the determination is that the projected movement of the device will take the device out of the current node area, step 520 calculates a total download time for data to that device. This initial download calculation time is based on the size of the data download and the standard (average) download speed at the current node zone. The standard speed is the download speed at the node area under a normal load capacity. After the calculation of the total download time, step 522 calculates a reduced download time at the current node zone and an increased download time at the projected new node zone such that the total download would be the same. After the calculations of the reduced and increased download speeds, step 524 adjusts the speed of the download to the specific device. In practice, the initial reduction in the download speed of the specific device that will be moving to another node zone will facilitate the increase of download speed(s) of other devices in the high capacity node area.
[0027] FIG. 6 illustrates an alternate embodiment of the method of the present invention. As with the method in FIG. 5 , steps 602 and 604 receive a data download request from a device and identify and locate the requested data for download. Step 606 identifies the requesting device. This identification function can also be part of 602 . In step 608 , there is a determination of the area tower through which the specific device made the data download request. Step 610 determines the current load volume at that node tower where the requesting device is located. Step 612 begins the load balancing function of the method of the present invention. This step, 612 , detects movement of devices receiving downloads at the current node area. When device movement is detected, step 614 projects the future movement of the device. Step 616 next determines whether any detected device movement takes the device outside of the current node area. When the determination is that the movement takes a device outside of the current node area and into an identified new node area, step 618 determines the current load at the newly identified node area. Based on the current load of the newly identified node area, step 620 determines whether load balancing can be implemented for a particular device. When the determination is that load sharing can be implemented for a particular device, step 622 calculates the total download time for the device based on the standard download speed at the current node area. After calculation of the total download time, calculation of a reduced download speed at the current node area and the increased download speed at the newly identified area is completed. In step 624 , the newly calculated download speeds are implemented.
[0028] It is important to note that while the present invention has been described in the context of a fully functioning cellular network system, those skilled in the art will appreciate that the components and processes of the present invention are capable of being distributed in the form of instructions in a computer readable storage medium and a variety of other forms, regardless of the particular type of medium used to carry out the distribution. The method of this invention provides significant advantages over the current art. The invention has been described in connection with its preferred embodiments. However, it is not limited thereto. Changes, variations and modifications to the basic design may be made without departing from the inventive concepts in this invention. In addition, these changes, variations and modifications would be obvious to those skilled in the art having the benefit of the foregoing teachings. All such changes, variations and modifications are intended to be within the scope of this invention. | A method and system identifies a data file for transfer to a user. The invention also detects the movement of the user device from which the data file transfer was made and calculates a projected path for movement of the user device. Based on the projected path of movement, the sections of the requested data file are transferred in parallel to node areas where the user device is projected to move according to the projected path. As the user enters a node area, the section of the data file downloaded to that node area is locally transferred to the user device and thereby substantially reducing download time of a large data file. | 7 |
RELATED APPLICATIONS(S)
[0001] This application is a continuation of International Patent Application No. PCT/CA2004/000258 filed on Feb. 24, 2004, which claims benefit of Canadian Patent Application No. 2 , 419 , 690 filed on Feb. 24, 2003, both of which are herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to gas turbine and rotary engines and, in particular, to turbo-compounded rotary engines or turbo-compounded internal combustion engine.
BACKGROUND OF THE INVENTION
[0003] Topping of the gas turbine engine cycle is well-known in the art. U.S. Pat. No. 4,815,282, U.S. Pat. No. 5,471,834 and U.S. Pat. No. 5,692,372, for example, show the prior attempts at integrating gas turbine with cycle-topping devices, such as piston-type internal combustion engines and eccentric rotary engines such as the so-called Wankel engine. Such cycle topping devices promise much-improved fuel efficiency for the integrated engine. All of the integrated engines disclosed in the above mentioned patents require an intercooler to cool the air before it enters the compressor section of the engine. Such intercooler are know to be bulky, heavy, etc. and, thus, not ideal for airborne applications.
[0004] For gas turbines destined for airborne applications, integration must not only successfully address improvements in cycle efficiency, but also provide a compact and lightweight package, and preferably one which does not significantly alter the envelope required versus that of a regular (i.e. non-compounded) gas turbine engine. Prior art attempts have not been as successful in these areas, and hence there exists a need for improved compact devices which offer not only improved efficiency, but also better power density, reliability, operability and so on.
[0005] Various types of cycle topping devices are known, including both non-rotating and rotating types. The present application is particularly concerned with eccentric rotary machines of all types useful in providing cycle-topping benefits to a gas turbine engine. Examples are shown in U.S. Pat. No. 5,471,834, U.S. Pat. No. 5,522,356, U.S. Pat. No. 5,524,587 and U.S. Pat. No. 5,692,372, to name a few, though there are certainly others available as well, as will be well-understood by the skilled reader.
SUMMARY OF THE INVENTION
[0006] It is an aim of the present invention to provide a compound cycle engine better suited for airborne applications than the prior art.
[0007] One general aspect of the present invention covers an integrated cycle topping device and gas turbine engine (the “integrated engine”) designed for low volumetric compression ratio (<3.5) which allows pre-mixed fuel upstream of the cycle topping device without the need of an inter-cooler. It provides for improved thermal efficiency and improved specific power.
[0008] In accordance with a further general aspect of the present invention, there is provided a compound cycle engine comprising a compressor and a turbine section, and at least one rotary engine providing an energy input to said turbine section, wherein said at least one rotary engine is mechanically linked to said turbine section to provide a common power output.
[0009] In accordance with another general aspect of the present invention, there is provided a compound cycle engine comprising a compressor section, a rotary engine section and a turbine section in serial flow communication with one another, and a primary output shaft providing the primary power output of the engine, wherein the rotary engine section and the turbine section are both drivingly connected to the primary output shaft.
[0010] In accordance with another general aspect of the present invention, there is provided a method of providing a non-intercooled cycle for a compound cycle engine, the engine having a rotary engine and a gas turbine connected in series, the method comprising the steps of: a) compressing air in a compressor section of the gas turbine, b) further compressing the air in the rotary engine, wherein the volumetric compression ratio in the rotary engine is below 3.5,c) mixing fuel with the compressed air to obtain an air/fuel mixture, d) combusting the air/fuel mixture, e) extracting energy from the combusted air/fuel mixture through expansion in the rotary engine, and f) further extracting energy from the combusted air/fuel mixture using a turbine section of the gas turbine.
[0011] In accordance with another general aspect of the present invention, there is provided a compound cycle engine comprising a compressor and a turbine section, and at least one cycle topping device providing an energy input to said turbine section, said compressor section compressing the air according to a pressure ratio PR gt , said at least one cycle topping device further compressing the air according to a volumetric compression ratio R vc , and wherein PR gt ×R vc <30.
[0012] In accordance with a sill further general aspect of the present invention, there is provided a method of providing a non-intercooled cycle for a compound cycle engine, the engine including a cycle topping device and a gas turbine connected in series, the method comprising the steps of: a) compressing air in a compressor section of the gas turbine using a pressure ratio PR gt , b) further compressing the air in the cycle topping device using a volumetric compression ratio R vc , c) mixing fuel with the compressed air to obtain an air/fuel mixture, d) combusting the air/fuel mixture, e) extracting energy from the combusted air/fuel mixture through expansion in the topping device, and f) further extracting energy from the combusted air/fuel mixture using a turbine section of the gas turbine, wherein the relationship between PR gt and R vc is maintained such that PR gt ×R vc <30.
[0013] In accordance with a still further general aspect of the present invention, there is provided a method of providing a cycle for a compound cycle engine, the engine including a rotary engine and a gas turbine connected in series, the method comprising the steps of: a) determining an auto-ignition limit of a fuel/air mixture; b) determining a pressure ratio associated with the auto-ignition limit; c) determining respective pressure ratios for a compressor section of the gas turbine and for the rotary engine; d) and selecting a combination of pressure ratios for the compressor section and the rotary engines, which provides an overall pressure ratio inferior to the pressure ratio determined in step b).
[0014] It is understood that the term “cycle topping device”, as used throughout this application and the attached claims, applies to any device adapted to provide an input to the turbine cycle, and not just rotary cycle topping devices such as a Wankel engine, sliding or pinned vane rotary machine (such as those disclosed in U.S. Pat. No. 5,524,587 or U.S. Pat. No. 5,522,356, respectively). Also, the term “compound cycle engine” as used throughout this application and the attached claims is intended to refer to an engine wherein at least two different types of engine (e.g. rotary engine and gas turbine, etc.) are integrated together to provide a common output. Further, the term “rotary engine”, as is used in the art and as is used herein, is used to refer to an engine in which gas compression and expansion occur in a rotary direction, rather than in a reciprocating manner such as in a piston-style internal combustion engine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Reference is now made to the accompanying Figures depicting aspects of the present invention, in which:
[0016] FIG. 1-3 are schematic diagrams of single shaft embodiments of an integrated engine comprising a gas turbine engine turbo-compounded by a rotary cycle topping device;
[0017] FIG. 4 is a Temperature-Entropy diagram of a turbo-compounded rotary engine cycle;
[0018] FIG. 5 is a Thermal Efficiency-Overall Pressure Ratio diagram illustrating the sensitivity of an intercooler thermal efficiency vs. the rotary engine volumetric ratio and the gas turbine pressure ratio;
[0019] FIG. 6 is a Combustion Inlet Temperature vs. Combustion Inlet Pressure diagram illustrating the sensitivity to auto-ignition vs. rotary engine volumetric ratio and gas turbine pressure ratio;
[0020] FIG. 7 is a schematic diagram of a free turbine embodiment of an integrated engine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Integrated engine embodiments are shown in FIGS. 1-3 for single shaft concepts where one (1) or two (2) closed volume combustion rotary engines can be coupled to a power turbine via a gearbox. FIG. 1 shows an integrated engine or compound cycle engine wherein the rotary engines are mounted at 90 degrees to the main engine axis. FIG. 2 shows another possible configuration wherein the rotary engines are mounted parallel to the main engine axis. FIG. 3 shows a rotary engine mounted in-line with the main engine axis.
[0022] Referring now more particularly to FIG. 1 , there is disclosed a single shaft engine 10 which includes an AGB/RGB 12 (accessory gearbox/reduction gearbox), a compressor 14 , two rotary machines or engines 16 and a power turbine 18 connected on a single shaft 20 . The turbine shown is a radial turbine, though other configurations are possible. The rotary engines 16 are connected to the shaft 20 by separate tower shafts 22 and 24 . The compressor 14 is preferably a centrifugal compressor, though need not necessarily be so, and is fed by an intake 26 . The compressor 14 communicates with the rotary engines 16 via an inlet scroll 28 , and the rotary engines 16 in turn communicates with the power turbine 18 via an outlet scroll 30 , to thereby provide a continuous gas path between compressor intake 26 and turbine exhaust 27 , as will be understood by the skilled reader. The compressor 14 acts as a turbocharger to the rotary engines 16 . A fuel pre-mixer 32 is integrated to the inlet scroll 28 of each rotary engine.
[0023] As shown in FIG. 1 , the shaft 20 is conjointly driven by the power turbine 18 and the rotary engines 16 . The rotary engine output shafts 22 and 24 can be mechanically linked to the shaft 20 by means of bevel gearing 34 .
[0024] Each rotary engine 16 includes a housing 23 which is liquid-cooled in a suitable manner, and having an associated cooling inlet 25 and outlet 27 . The cooling liquid, for instance oil, is circulated through the rotary engine housing 23 . As the liquid travels through or over the housing 23 , it picks up excess heat. The liquid is then pumped to a liquid cooler (not shown) where the liquid is cooled before being re-circulated back into the rotary engines 16 .
[0025] As can be readily appreciated from FIG. 1 , in use ambient air entering the gas turbine intake 26 is compressed by the compressor 14 , then it is routed to the pre-mixer(s) 32 where fuel is premixed with the air. The fuel/air mixture then enters the rotary engines 16 , gets further compressed with volume reduction. The compressed mixture is then ignited in the rotary engines, according to known techniques, before being expanded, the energy of such expansion further driving the rotary engine. The rotary engine exhaust gases are then ducted to the power turbine 18 for powering the turbine to produce further work before exhausting to the atmosphere via the turbine exhaust 27 .
[0026] The power developed by the rotary engines 16 and the power turbine 18 is used to drive a common load via the AGB/RGB 12 . As will be appreciated by the skilled reader, and is shown in with respect to the embodiment of FIG. 7 , the load can take the form of a propeller, a helicopter rotor, load compressor or an electric generator depending whether the engine is a turboprop, a turboshaft or an APU (Auxiliary Power Unit).
[0027] FIGS. 2 and 3 respectively show other embodiments of a single shaft engine wherein like components are identified by like reference numerals. A duplicate description of these components is herein omitted for brevity, as the skilled reader does not require such to understand the concepts disclosed.
[0028] The embodiment shown in FIG. 2 essentially differs from the embodiment shown in FIG. 1 in that the rotary engines 16 are mounted parallel to the main engine axis. The output shafts 22 and 24 of the rotary engines 16 are mechanically linked to the power turbine shaft 20 through the AGB/RGB 12 .
[0029] As can be clearly seen in FIG. 3 , the single shaft engine 10 can also be configured so that a single rotary engine 16 is mounted in-line with the power turbine shaft 20 . According to this reverse-flow configuration, the turbine shaft 20 is drivingly connected to the AGB/RGB 12 through the rotary engine output shaft 20 . Gearing (not shown) is provided to mechanically connect the power turbine shaft 20 to the rotary engine output shaft 22 .
[0030] As can be seen from FIGS. 1-3 , the rotary engine(s) can be mounted such that their shaft axes are either parallel or perpendicular to the gas turbine shaft axis.
[0031] FIG. 7 shows a free turbine embodiment where the rotary engine 16 5 (which can be either one or two rotary, or more, rotary engines, but referred to here in the singular for convenience) is coupled to the power turbine 18 only. The compressor 14 is mounted on a separate shaft 15 and is independently driven by a compressor turbine 17 coaxially mounted on the shaft 15 . The compressor 14 and the compressor turbine 17 act as a turbocharger to the rotary engine 16 . The outputs of the rotary engine 16 and power turbine 18 are linked mechanically through the AGB/RGB 12 to drive a common load (for instance a helicopter rotor, a propeller or a generator). The AGB/RGB provides the required speed reduction (if any, as desired) to permit coupling of the high speed power turbine 18 to the slower rotary engine 16 . The power turbine 18 and the rotary engine 16 both cooperate to provide the shaft horsepower required to drive the load coupled to the AGB/RGB 12 . This free turbine configuration is advantageous in that it provides the ability to have a high speed turbomachine section (more compact and efficient) since it is not directly mechanically coupled to the slower rotary engine. A smaller starter 39 can also be used on the free turbine configuration as the starter 39 can be provided on the output RGB (see FIG. 7 ) rather than having to drive the entire compound machine.
[0032] A cooling fan 34 is preferably drivingly connected to the rotary engine output shaft 22 to push cooling air through via appropriate ducting 36 to provide cooling air to the air cooled rotor 31 of the rotary engine. The cooling air is then expelled from the rotor to cool the cavity 35 between the compressor 14 and the hot scroll 30 . The machine housing 23 is cooled with suitable cooling liquid circulated through a suitable liquid conduit or housing jacket 37 , extending between the cooling inlet and outlet 25 and 27 , to thereby also extract excess heat from the housing of rotary engine 16 .
[0033] As is apparent from FIGS. 1-3 and 7 , the disclosed embodiments do not include an intercooler between the gas turbine compressor and the rotary engines. The prior art required an intercooler (see for example, U.S. Pat. Nos. 4,815,282 and 5,471,834) to cool the air before it enters the rotary machine in order to prevent pre-ignition of the fuel/air mixture, as the skilled reader will recognize that as a fuel/air mixture is increasingly compressed, in becomes susceptible to igniting. The embodiments of FIGS. 1-3 and 7 were not possible in the prior art, but are now possible through use of the cycle improvements according to another aspect of the present invention, as will now be described.
[0034] FIGS. 4 and 5 illustrate the high efficiency and specific power of the non-intercooled cycle. The results shown in FIG. 4 are for a constant volume combustion (CVC) rotary engine having a volumetric expansion pressure ratio (Rve) twice its volumetric compression ratio (R vc ), with no intercooler and a temperature T 4 at the exit of the rotary engines 16 set at 3100° F., the rotary engine being used with a gas turbine engine having a compressor pressure ratio (PR-GT) of 6. The temperature-entropy relations were obtained for five different values of volumetric compression ratio (R vc =1.2, R vc =1.5, R vc =2.0, R vc =3.0, and R vc =5). FIG. 4 also shows the value of the ratio ηth/SHP/W1 (ηth: thermal efficiency; SHP: shaft horse power; W1: airflow at the compressor intake) at the peak temperature of each curve.
[0035] The results in FIG. 5 are also for a constant volume combustion rotary engine with a peak temperature T 4 of 3100° F., the rotary engine having a volumetric expansion pressure ratio (Rve) twice its volumetric compression ratio (R vc ), and wherein the compressor pressure ratio (PR-GT) and the volumetric compression ratio (R vc ) are varied for constant leakages. The term “Net Shaft” in the axis “Thermal efficiency Net Shaft” is intended to mean directly on the output shaft of the engine. FIG. 5 shows three (3) curves for different values of compressor pressure ratio (PR-GT=8; PR-GT=6; and PR-GT=4) when no intercooler is used and three (3) additional curves for the same three different values of compressor pressure ratio (PR-GT=8; PR-GT=6; and PR-GT=4) but this time when an intercooler is used. On each curve, five different values of the volumetric compression ratio of the rotary engine (R vc =1.2; R vc =1.5; R vc =2; R vc =3; and R vc =5) are provided.
[0036] More particularly, the inventor has found that, and FIG. 5 clearly demonstrates that, when no intercooler is used, the thermal efficiency is optimal when the overall pressure ratio of the engine is about 40 . When the overall pressure ratio increases over 50 , the thermal efficiency drops. From FIG. 5 , it can thus be readily seen that under specific conditions (i.e. when the overall pressure ratio is below 50 ), the intercooler provides very little advantage to thermal efficiency which is more offset by its weight, size and cost. It can also be seen that after a certain point, the thermal efficiency starts to decrease as the volumetric compression ratio (R vc ) of the rotary engines 16 increases. Considering the much-additional weight and size that an intercooler entails, according to the present invention preferably, R vc is kept below 3.5 to provide optimal thermal efficiency without the need of an intercooler. FIG. 5 also clearly shows that the thermal efficiency of an integrated engine with no intercooler and having an R vc of 3 with a compressor pressure ratio (PR gt ) of 6 is almost as good as the thermal efficiency of an integrated engine with an intercooler. However, if the compressor is designed with a PR gt of 8, the R vc , must be reduced to 1.2 to provide a thermal efficiency equivalent to an integrated engine with an intercooler.
[0037] FIG. 6 shows four curves for two different values of the compressor pressure ratio (PR-gt=6 and PR-gt=4), the first pair of curves, which extends into the auto ignition zone, on the graph being for an engine with no intercooler and the two remaining curves at the bottom of the graph being for an engine with an intercooler. On each curve, five different values of the volumetric compression ratio of the rotary engine (R vc =1.2; R vc =1.5; R vc =2; R vc =3; and R vc =5) are provided.
[0038] As can be clearly seen in FIG. 6 , in accordance with the present invention, a limit line (shown with a thick stippled line in the Figure) between an “Auto-Ignition Zone” and a normal zone can be determined, based on the properties of the fuel and fuel/air mixture used. As demonstrated by FIG. 6 , a careful selection of overall pressure ratio, and a careful allocation of pressure ratios between the gas turbine and the rotary engines, can be used to achieve an “auto-ignition-free” cycle. If no intercooler is being used, the volumetric compression ratio (R vc ) in the rotary engines has to be kept below approximately 3 for a compressor pressure ratio (PR gt ) of 6 and below approximately 3.5 for a PR gt of 4 in order to be out of the auto-ignition zone. The analysis of FIG. 6 , clearly show that by reducing the compression ratio, the air heats up less and is then further away from auto-ignition temperature, thereby obviating the need for an intercooler.
[0039] In view of the foregoing, it appears that a clear advantage of limiting the volumetric compression ratio in the rotary engine below 3.5 is that while the high thermal efficiency is maintained, the reduced pressure and temperature prior to combustion allows to pre-mix the fuel with air prior to the rotary engines 16 to be done without auto-ignition and no need of an intercooler which is too bulky for many aerospace applications, and particularly so for commercial and commuter aircraft. As will be appreciated by the skilled reader, these cycle limitations are also applicable, and provide similar advantages, to a fuel injected configuration with spark ignition.
[0040] The low overall pressure ratio, i.e. preferably less than 50, with low rotary engine compression volumetric ratio, i.e. preferably less than 3.5, and gas turbine pressure ratio, i.e. preferably less than 6, gives a compact optimum thermal efficiency cycle, easier to design with lower loads, less stress and with reduced leakage in seals and gaps. This cycle is particularly attractive to rotary machines designed with controlled rotating gaps as opposed to high speed seals which are subject to wear.
[0041] It is noted that the rotary engine compression is described herein as a “volumetric compression ratio” because it is readily measurable in such closed volume combustion engines by reason of its closed volume combustion design, whereas the gas turbine compression described as a “pressure ratio” because of the gas turbine's continuous flow design, in which pressures are more easily measured instead of volume ratios.
[0042] The criteria to have a non-intercooled cycle with high thermal efficiency (40-45%) in a compact engine package with improved power to weight ratio can be defined as follows:
PR gt ×R vc 1.3 <30
[0043] where PR gt is the pressure ratio of the compressor(s) or gas turbine engine compression stage(s) feeding the rotary engine, and
R vc is the volumetric compression ratio of the rotary engine.
Typical values for optimum cycle efficiency are: PRgt=3-6 and Rvc=2-3.5, and full range of interest to meet above criteria 1.2<PRgt<9 and 1.2<Rvc<12
[0045] As long as the above conditions are met, it will be possible to operate without an intercooler to cool the air before it enters the rotary engines 16 . This advantageously provides for a very compact integrated engine package. Furthermore, limiting the overall pressure ratio below 50 also contributes to reduce the weight in that otherwise the wall thickness of the rotary engines would have to be thicker and heavier.
[0046] The above-described combination of compression ratio in the rotary engines and the gas turbine engine ensures that the temperature of the pre-mixed air/fuel mixture just prior to the combustion is below 1100° F. It is noted that the above “pressure rules” applies to diesel or kerosene/jet engines type of fuel.
[0047] The above description is meant to be exemplary only, and one skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. For example, it is understood that the rotary engine could be replaced by several rotary engines in parallel or series, or by other types of turbine cycle topping devices. For instance, a reciprocating engine could be used as well as a wave engine coupled to a combustor. Rotary engines are however preferred for compactness and speed compatibility (rotary engines have higher rotational speed potential vs. reciprocating engines). Another example is that instead of using pre-mix air/fuel upstream of the topping device, other configurations with fuel injection directly into the topping device after air compression, to be ignited with spark ignition, may also be employed. The terms “accessory gearbox” and “reduction gearbox” are used herein as those are familiar terms of gas turbine art, however the skilled reader will appreciate that the gearbox provided may be any suitable transmission system, and may or may not include speed reduction, depending on the application. Though one compression and one turbine stage is shown, any suitable number of stages may be provided as desired. Still other modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the equivalents accorded to the appended claims. | A compound cycle engine ( 10 ) comprises a compressor and a turbine section ( 14, 18 ), and at least one cycle topping device ( 16 ) providing an energy input to the turbine section ( 18 ). The compressor section ( 14 ) compresses the air according to a pressure ratio PR gt . The cycle topping device ( 16 ) further compresses the air according to a volumetric compression ratio R vc , and wherein PR gt ×R vc are selected, according to one aspect of the invention, to provide a cycle which permit a more compact and lighter compound cycle engine to be provided. | 5 |
RELATED APPLICATIONS
[0001] This is a continuation-in-part of co-pending U.S. patent aplication Ser. No. 09/702,266 filed on Oct. 31, 2000 in the names of Alexandra Gordon and Charles W. Grimes for “Packaging Device for Disc-Shaped Items and Related Materials and Method for Packaging Such Disks and Material” which, in turn, was a divisional of co-pending U.S. patent application Ser. No. 09/161,064 filed on Sep. 25, 1998 in the names of Alexandra Gordon and Charles W. Grimes for “Packaging Device for Disc-Shaped Items and Related Materials and Method for Packaging Such Disks and Material” which subsequently issued on Apr. 17, 2001 as U.S. Pat. No. 6,216,857.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates, in general, to a device for packaging and displaying a circular or disc-shaped media and other materials and a method for packaging such disc-shaped media and other materials and, in particular to containers and methods for initially packaging and thereafter repeatedly storing disc-shaped media together with other materials stored in containers of various sizes.
[0004] Still more particularly, the present invention further relates to a new and improved device for initially packaging and thereafter repeated storing of a disc-shaped media including a support element to receive and retain said disc-shaped media and means for attaching the packaging device to containers of varying sizes.
[0005] 2. Background of the Invention
[0006] Packaging and storage devices for media are generally known. Disc-shaped media, such as CD's, DVD's or CD-ROM's, encounter special problems in handling, packaging and storage due to their delicate, flat recorded surfaces. Such disc-shaped media is generally sold in plastic cases which are sometimes referred to as “jewel boxes.” Such cases are generally rectangular and have a mounting hub for holding the disc-shaped media by its center aperture. Such cases are usually kept after purchase of the disc-shaped media and utilized for re-packaging, of the disc-shaped media between usage. Such jewel boxes are impractical packaging containers for shipping because of their small dimensions and easy breakage, and they thus require substantial additional packaging material or placement in larger shipping containers.
[0007] Disc-shaped media is routinely sold with other materials (whether directly related to the content of the disc-shaped media, i.e., ancillary, or otherwise). At the present time, disc-shaped media in such “jewel boxes” is commonly packaged together with ancillary materials in larger rectangular shaped cardboard boxes for shipping, sale and packaging. The “jewel boxes” are necessary to reliably protect the disc-shaped media from contact with the ancillary materials in the larger cardboard boxes. Such plastic case/cardboard box combination package arrangements are not only expensive, they also do not lend themselves to easy and secure repeated re-storage of the disc-shaped media and ancillary materials. They are often damaged during initial opening and repeated re-storage. They are often unable after initial opening to securely re-store the disc-shaped media (in the jewel box) and the other materials together in the cardboard packaging in a manner to preclude contact with each other. They frequently become unsightly after initial opening and repeated re-storage. They are, themselves, difficult to handle and store.
[0008] Other types of packaging and storage devices are needed to organize, protect, ship, display at retail and store disc-shaped media sold and/or shipped in combination with ancillary materials.
[0009] A need also exists for devices which can effectively and efficiently organize, protect, ship, display at retail and store disc shaped media with other materials.
[0010] An opportunity exists that is not being commercially exploited at the present time to distribute disc-shaped recording media with materials that are either ancillary or wholly unrelated to the content of the disc-shaped media. This opportunity is not being exploited due to the lack of an effective container design and method for efficiently organizing, protecting, shipping, displaying at retail and storing disc-shaped media packaged with other materials.
SUMMARY OF THE INVENTION
[0011] The primary object of this invention is to provide a container in which and a method whereby disc-shaped media and ancillary materials stored in packages of various shapes and sizes can initially be packaged together in stacked relationship and, after removal and use, can easily be re-stored in stacked relationship in a manner so as to avoid contact there between.
[0012] Another object of this invention is to provide a container and method of packaging whereby the container and the disc-shaped media may be larger in area than the package or packages wherein the other material is stored.
[0013] Still another object of this invention is to provide a container and method of packaging whereby the disc-shaped media is protected from damage to its edges.
[0014] Yet another object of this invention is to provide a container and method of packaging whereby the container is formed using an injection molding process whereby the dimensions and structures of the upper portion of the container remains constant while the dimensions and structures of the bottom portion may be varied depending upon the size of the package or packages to which the container will be attached.
[0015] Another object of the present invention is to provide a container that may be attached to the package or packages by sliding the container over the top or the cap of the package or packages.
[0016] Still another object of this invention is to provide a container and a method of packaging that eliminates the need for a separate case (i.e., the need for a “jewel box”) for the disc-shaped media.
[0017] Yet another object of this invention is to provide a container and a method of packaging whereby during initial storage, shipping, retail presentation and re-packaging the disc-shaped media is securely held against movement in the planes both parallel and perpendicular to the plane of the disc-shaped media.
[0018] Still another object of this invention is to provide a container and a method of packaging whereby during initial storage, shipping, retail presentation and re-packaging the disc-shaped media is protected from contact with the other materials and from external forces.
[0019] Another important object of this invention is to provide a shipping container in which and a method of shipping whereby disc-shaped media and other materials can be packaged, presented, conveyed, distributed and stored.
[0020] Another important object of this invention is to provide an aesthetically unique and compelling device and method for presenting at retail disc-shaped media and other materials which may or may not be related to the content of the media.
[0021] Still another object with this invention is to provide a container and a method packaging whereby the seat and lid are removable and the seat and lid can be combined to create a permanent storage and restoring package for the disc-shaped media alone.
[0022] Another object of this invention is to provide a container and a method of packaging whereby a protective insert is placed in the container before the disc-shaped media to protect the disc-shaped media from contact with the other materials.
[0023] Another object of this invention is to provide a container and a method of packaging whereby a replaceable protective insert is placed in the container before the disc-shaped media to protect the disc-shaped media from contact with the other materials, which insert can be removed to access the ancillary materials and can be replaced after the ancillary materials are re-stored in the container and before the disc-shaped media is re-stored in the container.
[0024] Another object of this invention is to provide a container and method of packaging whereby the first chamber is within the removable lid and the disc-shaped media support member is a center post fixedly attached to and extending from the inside center of the lid.
[0025] To accomplish these and other objects, the container of this invention in its preferred form comprises a first member for the storage of disc-shaped media in a chamber or cavity, which container may be attached to storage devices of various shapes and sizes for the storage of materials other than the disc-shaped media. The chamber includes means for maintaining the disc-shaped media in a stable state within the chamber, including a structure defining support for the disc-shaped media whether by means of the annular opening at the center thereof or the perimeter thereof, such that the disc-shaped media is allowed to rotate, while limiting the linear movement of the disc-shaped media both perpendicular to and parallel to the plane of the media. The disc-shaped media may be sealed within the inner chamber by means of either a circular protective element or by means of a complementary cap or lid adapted to engage the first member. The protective element may be affixed by a variety of means, including heat-sealing to either the inner structure or perimeter of the first member, or both, or snapping engagement onto the first member by means of at least one protrusion on either the inner structure or perimeter of the first member, or both. Other attachment means, such as adhesives, or sealing compression fits, are contemplated. The first member may be attached to the storage device by a variety of means including heat sealing, snapping engagement, adhesives or a compression fit whereby the first member is engaged to the top of or cover to the package or packages. In such device, the first member and disc-shaped media may be larger in diameter than one dimension of the top of or cover to the package or packages. The first member includes a protective element along the perimeter thereof to ensure the integrity of the first member as well as to prevent damage to the edges of the disc-shaped media. Alternatively, the first member may engage and hold two or more packages in juxtaposition.
[0026] In the preferred method of packaging, disc-shaped media is inserted into and releasably retained within the chamber of the storage device by means of a cylindrical inner structure and sealed therein by means of a protective element. The storage device is then attached to the top of or cap to the package or packages containing the other material.
[0027] The above, as well as additional objects, features and advantages of the invention will become apparent in the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The novel features believed characteristics of the invention are set forth in the appended claims. The invention itself, however, as well as the preferred mode of use, further objects and advantages thereof, will best be understood by reference to the following detailed description of illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
[0029] [0029]FIG. 1 is an exploded perspective view of the novel disc packaging device of the present invention with the lid and disk media removed, illustrating the use of a one-piece annular collar member with an annular ring and lip;
[0030] [0030]FIG. 2 is a cut-away, cross-sectional side view of a portion of the novel disc packaging device of FIG. 1 when the lid is on the container, along line AA illustrating the resultant first and second chambers thereof;
[0031] [0031]FIG. 2A is an alternative embodiment of the device shown in FIG. 2, wherein a protective element is inserted between the first and second chambers;
[0032] [0032]FIG. 2B is an alternative embodiment of the device shown in FIG. 2A, showing an alternative method of insertion of the protective element between the first and second chambers;
[0033] [0033]FIG. 2C is a further alternative embodiment of the device shown in FIG. 2A, showing, a further alternative method of insertion of the protective element between the first and second chambers;
[0034] [0034]FIG. 3 is a top plan view of the novel disc packaging device of the present invention illustrating the alternative use of abutments and protrusions affixed to the inside wall of the container;
[0035] [0035]FIG. 3A is a cut-away, cross-sectional side view of a portion of the device shown in FIG. 3, along line B-B, with a disc-shaped media and other materials inserted and the lid affixed;
[0036] [0036]FIG. 3B is a cut-away, cross-sectional side view of an alternative embodiment of the novel disc packaging device of the present invention illustrating the alternative use of the upstanding rim of the base and the inside wall of the cover in place of the abutments and protrusions of FIG. 3;
[0037] [0037]FIG. 3C is a cut-away, cross-sectional side view of an alternative embodiment of the novel disc packaging device of the present invention illustrating the alternative use of the outer surface of the cover and the inner surface of a supplementary cover in place of the abutments and protrusions of FIG. 3;
[0038] [0038]FIG. 4 is a top plan view of the novel disc packaging device of the present invention illustrating the alternative use of a center annular post support for the disc-shaped media suspended from spokes;
[0039] [0039]FIG. 4A is a cut-away, cross-sectional side view of the device shown in FIG. 4, along line C-C, with a disc-shaped media and other materials inserted and the lid affixed;
[0040] [0040]FIG. 5 is a top plan view of the novel disc packaging device of the present invention illustrating fingers that extend from a frame carried by the side wall of the container and that provide center support for the disc-shaped media;
[0041] [0041]FIG. 5A is a cut-away, cross-sectional side view of the device shown in FIG. 5, alone, line D-D, with a disc-shaped media and other materials inserted and the lid affixed;
[0042] [0042]FIGS. 6A and 6B are cross-sectional views of alternate embodiments of the packaging device of the present invention depicting two different methods of mounting the disc-shaped media support member to the device outer wall;
[0043] [0043]FIG. 7 is a cut-away, cross-sectional side view of an alternative embodiment of the present invention with disc-shaped media and other materials inserted, the protective element inserted and the lid closed, in which the first chamber in which the disc-shaped media is stored is in the cover;
[0044] [0044]FIG. 7A is a cut-away, cross-sectional side view of an alternative embodiment of the device shown in FIG. 7, wherein the disc-shaped media is inserted into a protective envelope that is affixed to the inner surface of the cover;
[0045] [0045]FIGS. 8 and 8A are side perspective, partially cut-away, cross-sectional views of alternative embodiments of the present invention, illustrating the use of the “lid” of the embodiment shown in FIG. 7 as the base, thereby allowing the portion of the invention defining the second chamber to be of an irregular shape (FIG. 8) or to have deformable construction (FIG. 8A);
[0046] [0046]FIG. 9 is a cut-away, cross-sectional side view of an alternative embodiment of the present invention in which the disk media is located in the lid and the lid and the container include second and third chambers, respectively, for storing other material;
[0047] [0047]FIG. 10 is a cut-away, cross-sectional view of another embodiment of the present invention in which the second chamber in the container for storing other materials includes a second opening separate and distinct from the lid and a removable cover such that access to the second chamber can be attained without removing the lid;
[0048] [0048]FIGS. 11 and 11A are cut-away, cross-sectional side views of another embodiment of the device shown in FIG. 10 in which the method of mounting shown in FIG. 6A is utilized and wherein the removable cover for the second chamber can be mated with the removable cover for the first chamber to form a mini-packaging device shown in FIG. 11A;
[0049] [0049]FIG. 12 is a cut-away, cross-sectional side view of an alternative embodiment of the device shown in FIGS. 11 and 11A in which the method shown in FIG. 3B for retaining the disc-shaped media is utilized and in which the two covers threadably engage the base and, when removed, can be threaded together to create a mini-packaging unit;
[0050] [0050]FIGS. 12A and 12B are cut-away, cross-sectional side views of alternative embodiments of the device shown in FIG. 12, wherein the two covers slidably engage after removal (FIG. 12A) or threadably engage after removal (FIG. 12B);
[0051] [0051]FIG. 13 is a cut-away, cross-sectional side view of another embodiment of the present invention in which a concave cavity on the exterior side of the cover for the device forms the first chamber for the disc-shaped media and a seal encloses the disc-shaped media within the concave cavity;
[0052] [0052]FIG. 14 is an exploded perspective view of a further alternative embodiment of the novel disc packaging device of the present invention with the lid, disk media and protective element removed, illustrating the use of a sealed base; and
[0053] [0053]FIG. 15 is an exploded perspective view of a further alternative embodiment of the novel disc packaging device of the present invention in which the disk media is sealed within the lid, and the base is separately sealed, and the lid and base are detachably joined together by an outer packaging skin that can be severed with a pull string.
[0054] [0054]FIG. 16 is a cut-away, cross-sectional view of a further alternative embodiment of the novel disc packaging device of the present invention in which in which the packaging device is larger than the cover to the container to which it is attached and fits about the cover or lid to said container.
[0055] [0055]FIG. 17 is a cut-away, cross-sectional view of a further alternative embodiment of the novel disc packaging device of the present invention in which in which the packaging device is larger than the cover to the container to which it is attached and is attached to the container by means of engagement to the inside rim of the container.
[0056] [0056]FIG. 18 is a cut-away, cross-sectional view of a further alternative embodiment of the novel disc packaging device of the present invention in the which the packaging device is formed from a two part injection mold wherein the dimension and size of the upper portion remain constant while the dimension and size of the lower portion may be varied so as to conform to the dimensions of the container to which the packaging device is to be attached.
[0057] [0057]FIG. 19 is a perspective view of a further alternative embodiment of the novel disc packaging device of the present invention in which the packaging device is attached to two or more containers.
[0058] [0058]FIG. 20 is a cut-away, cross-sectional view of the embodiment of FIG. 19 in which the disc-shaped media is stored on the bottom of the packaging device, facing the containers to which it is attached.
[0059] [0059]FIG. 21 is a cut-away, cross-sectional view of the embodiment of FIG. 19 in which the disc-shaped media is stored on the top of the packaging device, separated from the containers to which it is attached.
DETAILED DESCRIPTION OF THE INVENTION
[0060] With reference now to the figures and in particular with reference to FIG. 1, there is shown a front view of the disc packaging device 10 of the present invention. As illustrated, disc packaging device 10 includes a lower base component or container 12 and an upper cover component or lid 14 . Lower base component 12 and upper cover component 14 are utilized to form a generally cylindrical packaging device of dimension slightly larger than the disc shaped recording media to be stored. End plates 16 and 18 cooperate with lower base component 12 and upper cover component 14 to fully enclose the cylindrical packaging space defined thereby.
[0061] The lower base component 12 of the embodiment of this invention shown in FIGS. 1 and 2 includes a side wall 20 . The side wall can be constructed from either cardboard (i.e., natural fiber material) or plastic (i.e., man-made synthetic material) or other material suitably rigid for the base component to retain its shape, including metal, e.g., as in a vacuum sealed, canned product.
[0062] The base component 12 can be designed to threadably receive the bottom plate 16 which is of conventional design, made of stiff cardboard, plastic, metal or some similarly rigid material and used as a cover-all screw cap on a very wide variety of containers. Alternatively the bottom plate 16 can nest inside the side wall 20 where it is held by friction, stapling, gluing or some other means. The side wall 20 has an upper section 22 and the upper section 22 can be threaded to accommodate the upper cover component 14 although in the embodiment shown in FIGS. 1 and 2 the cover is made of plastic and snaps on in a conventional manner.
[0063] As best seen in FIG. 2, the upper section 22 is defined by an outer wall 24 , an inner wall 26 and a rim 28 . The cover component 14 has a side wall 30 defined by an outer wall 32 , an inner wall 34 and a rim 36 . The diameter of the inner wall 34 of the cover component is slightly greater than the diameter of the outer wall 24 of the base component. In the embodiment shown in FIGS. 1 and 2, there is an inner structure 40 which provides circumferential support for a disc shaped media 42 stored within the packaging device 10 . The structure 40 comprises an annular collar 44 having an annular ring 46 and an annular lip 48 . The inner structure 40 nests within the lower base component 12 . The annular collar 44 has an outer diameter greater than the diameter of the inner wall 26 of the base component such that the annular collar extends beyond the inner wall 26 and sits on top of the base rim 28 . The annular ring 46 has an outer diameter less than the diameter of the inner wall 26 , such that the annular ring nests inside the inner wall 26 . The annular lip 48 has an inner diameter less than the outer diameter of the disc shaped media 42 . Thus, the disc shaped media will rest on the annular lip, inside the annular ring. In this way, movement of the disc shaped media in the plane of the disc shaped media is precluded by the annular abutment 46 . Movement of the disc shaped media perpendicular to its plane is prevented in one direction by the annular lip 48 . When the cover component 14 is affixed to the base component 12 , the cover plate 18 acts to preclude movement of the disc shaped media in the opposite perpendicular direction to the plane of the disc shaped media.
[0064] In the embodiment disclosed in FIG. 2A, a protective member 50 is attached to the annular lip 48 . The protective member can be made of plastic film or any other conventional material to provide a barrier between the disc shaped media and other materials 52 which can be stored in the base component 12 of the packaging device 10 . The protective member can be permanently affixed to the annular lip or it can be affixed at the time of assembly and shipment and removed by the consumer after purchase, i.e., at a time when further “rough handling” that would cause interaction between the disc shaped media and the other materials is less likely to occur.
[0065] In an alternative embodiment disclosed in FIG. 2B, the protective element is removable and sized to seat on the annular lip 48 between the annular lip 48 and the disc shaped media. The protective element is round like the disc shaped media and has a central opening into which one's finger can be inserted to engage, lift and remove the protective element and subsequently engage, lift and replace the protective element.
[0066] In an alternative embodiment disclosed in FIG. 2C, the protective element 50 B is flexible and is removably inserted within the lower base component beneath the annular lip 48 and on top of the other materials 52 placed therein. The protective element is sized to correspond to the interior wall 26 and has a central opening into which one's finger can be inserted to engage, lift and remove the protective element and subsequently engage, lift and replace the protective element. Alternatively, the protective element can be provided with a lift tab or some other conventional means whereby it can be grabbed and removed.
[0067] In the alternative embodiment shown in FIGS. 3 and 3A, the inner structure 40 is modified. The annular collar 44 with annular ring 46 and annular lip 48 is replaced by discrete abutments 54 and discrete protrusions 56 . Collectively, the abutments 54 and protrusions 56 are positioned within the lower base component 12 around the circumference of the inner wall 26 spaced below the rim 28 , affixed to the inner wall 26 , so as to perform the same function as the annular ring 46 and annular lip 48 . Specifically, the abutments 54 preclude movement of the disc shaped media in the plane of the disc shaped media i.e., performing the same function as the annular ring 46 . Similarly, the protrusions 56 are positioned about the inner wall 26 and collectively preclude movement of the disc shaped media in a direction perpendicular to plane of the disc shaped media i.e., performing the same function as the annular lip 48 .
[0068] [0068]FIG. 3B shows a further alternative embodiment wherein the disc shaped media is seated on the rim 28 and movement of the disc shaped media perpendicular to its plane is prevented in one direction by the rim 28 . When the cover 14 is affixed to the base component 12 , movement of the disc shaped media in the plane of the disc shaped media is precluded by the inner wall 34 of the cover 14 and inner surface 14 a of the cover 14 acts to preclude movement of the disc shaped media in the second, opposite perpendicular direction to the plane of the disc shaped media.
[0069] [0069]FIG. 3C shows a further alternative embodiment wherein the disc shaped media is seated on the outside surface 14 b of the cover 14 and movement of the disc shaped media perpendicular to its plane is prevented in one direction by a supplementary cover 144 that snaps onto the cover 14 . When the supplementary cover 144 is affixed to the cover 14 , movement of the disc shaped media in the plane of the disc shaped media is precluded by the inner wall 144 a of the supplementary cover 144 and the inner wall 144 b of the supplementary cover 144 acts to preclude movement of the disc shaped media in the second, opposite perpendicular direction to the plane of the disc shaped media. The supplementary cover 144 can include a chamber 144 d and a protective element 50 b can be inserted to prevent contact between the disc shaped media and whatever materials 52 a are placed in the chamber 144 d.
[0070] In the alternative embodiment seen in FIGS. 4 and 4A, the inner support structure 40 is replaced with an inner support structure 58 that provides center support for the disc shaped media as opposed to the circumferential support provided by inner structure 40 . In the embodiment shown in FIGS. 4 and 4A, the alternative inner structure 58 includes an annular ring 60 and spokes 62 extending therefrom. As seen in FIG. 4A, the annular ring 60 has a raised portion 64 on which the disc-shaped media 42 sits, The spokes 62 each have a finger portion 66 which extends upwardly and outwardly such that when the structure 58 is inserted into the base component 12 , the fingers 56 frictionally engage the inner wall 26 and sit on the upper rim 28 . The structure 58 can include webbing between the fencers 56 (ala the webbing in a duck's foot) comprised of a thin material to provide protection for the disc shaped media 42 from the other materials 52 . Inside the annular ring 60 would be left open to allow the consumer, after removing, the cover 14 , to insert their finger into the annular ring and to thereby remove both the disc shaped media 42 and the structure 58 .
[0071] [0071]FIGS. 5 and 5A show a further alternative inner structure 68 comprising an annular collar 70 from which fingers 72 extend inwardly. At the ends of the fingers 72 are upstanding projections 74 . The annular collar 70 nests inside the inner wall 26 and sits on the rim 28 in the same manner as the inner structure 40 in the embodiment shown in FIGS. 1 and 2. The upstanding projections 74 cooperate to provide a center support structure for the disc shaped media.
[0072] As seen in FIGS. 6A and 6B, the fingers 72 in the embodiment shown in FIGS. 5 and 5A do not necessarily need to be suspended from an annular collar. Alternatively, the could be clipped to the side wall 20 as seen in FIG. 6A or they could be screwed into the side wall 20 as shown in FIG. 6B.
[0073] In an alternative embodiment shown in FIG. 7, a center support structure is provided for the disc shaped media in the upper cover component 14 . Specifically, projections 80 extend from the inside wall 82 of the end plate 18 . These projections 80 cooperate to provide secure support for the disc shaped media in the cover component 14 . A protective element 84 can be provided which is either removably nested within the cover as shown or which can be inserted at the time of manufacture and removed and discarded by the consumer after purchase. The cover 14 can engage the base component 12 in any variety Of conventional ways, e.g., snap on, telescope on, screw on, etc.
[0074] In a further alternative embodiment shown in FIG. 7A, the disc shaped media is encased within an envelope 84 a made of plastic or some other suitable material and which is affixed to the inside wall 82 of the end plate 18 . The envelope is either removably or permanently affixed, e.g., by gluing, with double-sided tape, or by other conventional means. The envelope can itself constitute a re-useable packaging container for the disc shaped media that either remains affixed to the plate 18 or can be removed from the plate 18 , e.g., so that the cover 14 can be discarded. Or the disc shaped media can be packaged within a packaging sleeve (not shown) ail of which can then be inserted into the envelope and then removed from the envelope once the envelope is opened.
[0075] [0075]FIGS. 8 and 8A show further alternative embodiments of the present invention. In FIG. 8, the fact that the disc shaped media is stored within the cover component 14 allows for an alternative construction of the container 12 . In this alternative embodiment, the cover 14 serves as the “base”. The alternative base 90 , in which the other materials, in this case, a doll 92 , are stored, has an end wall structure 94 which frictionally encases the inner wall 96 and seals the chamber in the base 90 . Alternatively, wall 94 can be provided with threads so that it will threadably engage corresponding threads on the inside wall 96 . The cover 14 and base 90 can be attached in the same manner as heretofore been discussed in connection with other embodiments.
[0076] In the embodiment showing in FIG. 8A, the cover 14 once again carries the disc shaped media 42 and thereby allows the base 12 to be of a deformable construction 98 . The deformable member 98 has a rigid internal support structure 100 which is designed to frictionally or threadably engage the cover 14 .
[0077] In the alternate embodiment shown In FIG. 9, the disc shaped media is stored in a first chamber 102 in the lid 14 defined by an annular support 40 similar in construction to the embodiment of FIG. 7, except that the lid includes a second chamber 104 defined by an outer wall 106 for other materials and the base 12 includes a third chamber 108 . In the alternate embodiment shown in FIG. 10, which is similar in construction to the embodiment of FIG. 4, there is provided an additional opening 110 in the container 22 and a cover 116 for closing the opening 110 . The cover 116 can be removed to gain access to the chamber 104 without removing the cover 14 .
[0078] In the alternative embodiment shown in FIGS. 11 and 11A, an inner structure 40 a is provided that is a slightly modified version of the inner structure 40 shown in FIG. 2, in that it includes an annular wall 45 that extends around the entire circumference of the annular collar 44 and engages the outer surface of the wall of the base 12 , and the cover 14 is configured to engage not the base 12 , but rather, the annular wall 45 . An additional opening 110 is provided as in the embodiment of FIG. 10, and a cover 116 a is provided that is a slightly modified version of the cover 116 of FIG. 10, in that it includes not only an outer annular wall 116 b for engaging the outer surface of the wall of the base 12 , but also an inner annular wall 116 c for engaging the inner surface of the wall of the base 12 . The circumferential dimension of the outer surface 116 d of the wall 116 b of the cover 116 a is identical to the circumferential dimension of the outer surface 45 d of the wall 45 , such that the covers 14 and 116 a can be removed and the cover 14 which matingly engaged the wall 45 will matingly engage the outer wall 116 b of the cover 116 a , as shown in FIG. 11A. In this way, as also shown in FIG. 11A, the covers 14 and 116 a can be used together as a mini-packaging device for the disc shaped media 42 . In the embodiment shown, the inner wall 116 c helps to securely retain the disc shaped media against movement. However, it is understood that the benefits of the invention could be achieved without such inner wall, or utilizing one of the other retaining methods disclosed herein.
[0079] In the alternative embodiment shown in FIG. 12, the disc shaped media seats on the rim 28 as in the embodiment shown in FIG. 3B, but the cover 14 x does not snap onto the base 12 , but rather, threadably engages it. Furthermore, the bottom 12 x of the base 12 is flared outwardly and contains internal threads that are of the same dimension as the internal threads of the cover 14 x . The cover 116 x includes mating external threads such that the cover 116 x can be threaded into the flared bottom 12 x of base 12 . In this way, the covers 14 x and 116 x can be removed from the base 12 and threadably engaged to form a mini-packaging unit for the disc shaped media.
[0080] In the alternative embodiments of FIGS. 12A and 12B, the need to flare out the bottom of the base 12 is eliminated. In FIG. 12A, the base 12 y receives a bottom cover 116 y that includes an overlapping portion 117 y , the outer surface 118 y of which is of equal dimension to the outer surface 118 y of which is of equal dimension to the outer wall of the base 12 y , such that covers 14 y and 11 y can be slidably engaged to form a mini-storage unit for the disc-shaped media. In FIG. 12B, the base 12 z has an external threaded portion 119 z and an internal threaded portion 120 z each of which extends beyond the center line “C” of the wall of the base 12 z . In this way, when the covers 14 z and 116 z are removed, they can be threadably engaged to form a mini-storage unit for the disc-shaped media.
[0081] [0081]FIG. 13 shows a further alternative embodiment, wherein the cover 244 nestingly seats within the base 12 and the disc shaped media 42 is placed within the concave recess 246 of the cover 244 . A seal 248 made of plastic or other suitable material is applied to the cover 244 to hold the disc shaped media within the cover 244 until the seal is removed by the user. The disc shaped media can be retained against movement within the cover 244 as a result of contact with the side walls 250 , bottom wall 252 and seal 248 , or by utilization of any of the other methods taught herein.
[0082] [0082]FIG. 14 shows a further alternative embodiment wherein the base 12 is a separately manufactured container of miscellaneous content, that includes a slightly concave end 251 , the depth 252 of which exceeds the combined thickness of a disc shaped media 42 and a protective element 50 which are seated within the concave end 251 and held there by cover 14 which snaps onto base 12 . In an alternate embodiment, a protective element is not used or the disc shaped media is packaged in an envelope (not shown).
[0083] [0083]FIG. 15 shows a further alternative embodiment wherein the disc shaped media is mounted and sealed within cover 14 , e.g., as taught herein in connection with other embodiments, and cover 14 is attached to base 12 by paper packaging material skin 0 1 that binds the cover 14 and base . 12 together. Cover 14 is separated from base 12 by pulling string 302 which tears the skin 301 and breaks the circumferential attachment between cover 14 and base 12 .
[0084] It would be understood that in each embodiment, a container device is provided in which disc shaped media can be packaged, distributed, displayed at retail and, if desired, restored with other materials and that, in effecting such usage, discrete chambers are provided for the disc-shaped media and for the other materials so as to prevent contact between the disc-shaped media and the other materials. In the embodiments shown in FIGS. 1 through 6B, the inner structure, whether it is the annular collar of FIG. 1, or the discretely positioned abutment/protrusion clips of FIG. 3, or the upstanding rim in FIG. 3B, or the lid and supplemental lid of FIG. 3C, or the “spider” structure of FIG. 4, or the “trap” structure of FIG. 5, in each case is located in and helps define a first chamber in the lower base component 12 . Underneath this first chamber is a second chamber. The first chamber receives and securely holds, despite repeated removal and re-packaging, the disc shaped media. The second chamber receives the other materials and keeps these materials separate from the disc shaped media. The need for a separate “jewel case” for the disc shaped media is thus completely eliminated.
[0085] It would be understood that the shape of the container can be varied without departing from the scope of the present invention, e.g., the cylindrical base 12 can be square or rectangular so long as the outer wall of the collar 40 corresponds and the collar includes spacers from the outer wall of the collar to the annular ring and annular lip of the present invention. Similar adjustments could be made to the other embodiments as would be apparent to those skilled in the an having reviewed this disclosure. The abutment/protrusions clips of FIG. 3 could be mounted on a non-cylindrical shaped base, as could the spider structure of FIG. 4 or the trap structure of FIG. 5.
[0086] It would be understood by those skilled in the art that the function of the annular ring of FIG. 1 or the abutments of FIG. 2 could be performed by an appropriately dimensioned inner wall 26 of the container 12 .
[0087] It would be further understood that while several methods of attaching the annular collar of FIG. 1, the abutment/protrusion clips of FIG. 2, the spider structure of FIG. 3 and the trap structure of FIG. 4 have been shown, those skilled in the alt after having reviewed this disclosure could devise other means of attachment without departing from the scope of the present invention.
[0088] It would be further understood by those skilled in the art that the device and method of this invention can accommodate one or more disc shaped media, e.g., through the insertion of protective elements therebetween.
[0089] Illustrated in FIGS. 16-21 are additional embodiments of the present invention comprising a first member or member 500 adapted to receive the disc-shaped media 42 , and thereafter to be affixed to the cover or top 502 of a container or containers 503 , which container or containers may be of any size or shape, regardless of whether smaller or larger in area than the member 500 . In the embodiments shown in FIGS. 16-21, provided at the center of the member 500 is a cylindrical projection 504 which serves the purpose of maintaining the disc shaped media 42 in a stable state within the cavity 506 formed by the member 500 , by receiving and retaining the disc-shaped media 42 such that the disc-shaped media 42 is prevented from moving linearly parallel to the plane of the disc-shaped media 42 , while allowing the disc-shaped media 42 to rotate around the cylindrical projection 504 . Toward that end, the outer diameter of the cylindrical projection 504 must be slightly less than the diameter of the annular aperture in the disc-shaped media 42 such that the cylindrical projection 504 may be in frictional contact with or loosely contact the annular aperture in the disc-shaped media 42 . It would be understood that the other means of maintaining the disc media in stable state taught herein, e.g., by means of members engaging the outer edge of the disc media, may alternatively be employed without departing from the scope of the present invention.
[0090] The disc-shaped media 42 is further protected within the member 500 by means of raised shoulder or edge element 508 encircling the perimeter the member 500 , which shoulder or edge element 508 serves the dual purpose of forming the outer wall of the cavity 506 and protecting the disc-shaped media 42 from damage to the edges of the media 42 caused by contact with external forces being applied to the member 500 . In the preferred embodiment, the shoulder or edge element 508 is composed of a stiff material having some flexibility such as plastic such that it can deform so as to absorb and redistribute any force applied thereto. A downwardly extending extension 510 may also be provided, which extension 510 serves to increase the surface area of the shoulder or edge element 508 to thereby supplement the protection to the disc-shaped media 42 . The height of shoulder or edge element 508 should be sufficient that it is at least coplanar with the upper surface of the disc-shaped media 42 , although it is preferable if its upper surface is above the upper surface of the disc-shaped 42 .
[0091] A separate annular downwardly extending skirt member 512 is provided to attach the member 500 to the cover or top 502 of the container or containers 503 . In the preferred embodiment, the skirt member 512 is also composed of a stiff material having some flexibility so that it can deform to match the contours of the cover or top 502 . This deformation also serves to help retain the member 500 in place on the cover or top 502 by allowing the skirt member 512 to “grip” the cover or top 502 . It should therefore be appreciated that the inner dimensions of the skirt member 512 should be slightly smaller than the external dimensions of the cover or top 502 so that the member 500 may be secured to the top of the container 503 by means of the compression fit between the skirt member 512 and cover or top 502 .
[0092] In an alternative embodiment illustrated in FIG. 17, the skirt member 512 may also engage the cover or top 502 about an inner perimeter of the cover or top 502 . In such embodiment, the external dimension of the skirt member 512 should be slightly larger than the internal dimension of the inner perimeter of the cover or top 502 such that the deformation of the skirt member 512 serves to provide an outwardly directed force that increases the frictional contact between the skirt member 512 and inner perimeter of the cover or top 502 .
[0093] Additional structures may also be included within the member 500 to ensure the stability and integrity of the disc-shaped media 42 . For example, as seen in FIG. 17, one or more outwardly extending protrusions 514 may be provided at the top of the cylindrical projection 504 , which protrusions 514 serve to prevent the disc-shaped media 42 from sliding off the cylindrical projection 504 . The protrusions 514 and the cylindrical projection 504 in such embodiment should be at least slightly flexible so as to allow the disc-shaped media 42 to be “snapped over” the protrusions 514 in order to repeatedly attach and remove the disc-shaped media 42 from the cylindrical projection 504 .
[0094] Inner and outer raised shelves 516 , 518 as seen in FIG. 16 may also be provided in the member 500 so as to raise the disc-shaped media 42 above the floor 520 of the member 500 , so as to prevent damage to the media surface of the disc-shaped media 42 . The inner raised shelf 516 may be disposed about the cylindrical projection 504 so that it does not come into contact with the media surface. The outer raised shelf 518 , however, may or may not come into contact with the media surface. Accordingly, if necessary, such shelf 518 should be composed of or covered by a material that will not damage the media surface.
[0095] [0095]FIG. 18 illustrates an alternative embodiment of the present invention in which the member 500 is formed by injection molding using a mold that has two halves—an upper mold 522 and a lower mold 524 , which molds 522 , 524 are joined at centerline 526 . It should be appreciated that the dimensions and structures formed by the upper mold 522 can be made constant, inasmuch as the dimensions of the disc-shaped media 42 never change, and therefore the raised shoulder or edge element 508 and cylindrical projection 504 do not need to change. The lower mold 524 , however, can be varied depending upon the shape and size of the container or container 503 to which the member 500 is to be attached. This embodiment eliminates the need for manufacturing numerous different molds so as to accommodate discs 42 and containers 503 of varying sizes. A manufacturer need only identify the size of the disc-shaped media 42 and the size and shape of the container or containers 503 , and match the two molds 522 and 524 appropriate for each together.
[0096] Illustrated in FIGS. 19 through 21 is the attachment of the member 500 to two or more containers simultaneously. In such embodiments, the skirt member 512 is sized so as to conform to the shape of the covers or tops 502 of the containers 503 . This embodiment has particular applicability for tube-shaped containers 503 such as tennis ball containers or containers for potato chips, for example. The advantage of such embodiment is that it allows for the positive juxtaposition of products, as well as allowing the products to be packaged in an alternating arrangement (e.g., “head” to “toe”) in shipping cartons, which saves packaging space. Furthermore, it should be appreciated that while the figures show the member 500 being attached to two containers 503 , any number of containers 503 may be covered/attached by this embodiment.
[0097] Furthermore, it should be appreciated that the disc-shaped media 42 may be situated in the cavity 506 created in the member 500 in several configurations, including the inwardly facing configuration shown in FIG. 20 as well as the outwardly facing configuration shown in FIG. 21. In the former, a separate protective element or seal 528 may be provided so as to prevent contact between the disc-shaped media 42 and the containers 503 . In the latter configuration, a cover 530 or lid may be provided to cover the member 500 and further serve to retain the disc-shaped media 42 within the cavity 506 . Of course, the protective element 528 or cover 530 may be used in any of the other embodiments already described.
[0098] Having thus described the invention with particular reference to the preferred forms thereof, it will be obvious that various changes and modifications can be made therein without departing from the spirit and scope of the present invention as defined by the appended claims. | A packaging device is provided for packaging at least one disc-shaped item such as a CD-ROM or a DVD. The packaging device includes a first member for the storage of disc-shaped media in a chamber or cavity, which container may be attached to storage devices of various shapes and sizes for the storage of materials other than the disc-shaped media. The chamber includes means for maintaining the disc-shaped media in a stable state within the chamber, such that the disc-shaped media is allowed to rotate, while limiting the linear movement of the disc-shaped media both perpendicular to and parallel to the plane of the media. The disc-shaped media may be sealed within the inner chamber by means of either a circular protective element or by means of a complementary cap or lid adapted to engage the first member. The first member is attached to the storage device by means of engagement of the first member with the top of or cover to the package or packages. In such device, the first member and disc-shaped media may be of a larger diameter than one dimension of the top of or cover to the package or packages. Alternatively, the first member may engage and hold in positive juxtaposition multiple packages. The first member includes a protective element along the perimeter thereof to ensure the integrity of the first member as well as to prevent the edges of the disc-shaped media from being damaged. A method is further provided for packaging such disc-shaped item and other material within the packaging device. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser. No. 07/726,912 filed Jul. 8, 1991 abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a novel thermotropic liquid crystal polyester, shaped articles comprising the same, and packaging materials and containers having high gas barrier properties.
2. Description of the Related Art
Polyesters, in particular polyethylene terephthalate (hereinafter sometimes referred to as "PET") are excellent in hygienic property, odor-keeping property, processability and like properties and are hence widely used as containers for seasonings such as soy sauce and sauce, soft drinks such as juice, cola and soda pop, draft beer, cosmetics, medicines and the like. It is expected that polyester bottles will be more widely used as replacement for glass bottles, since they are, in addition to the above features, lighter than glass and pressure-proof and of high gas barrier properties. For polyester containers, however, further improvement of gas barrier property is strongly desired since bottles for lager beer, wine and similar alcoholic drinks are stored for a long time and those for carbonated drinks are getting smaller in their size so that their surface areas per capacity are increasing, whereby there is more strictly required prevention of invasion of oxygen from outside or reduction in the amount of carbon dioxide gas dissipated outwardly. The gas barrier property of PET is very difficult to improve because it has already attained a considerably high level and that any improvement should not impair the processability into containers and the mechanical properties such as pressure-proofness. Various processes have been proposed to improve the gas barrier property of PET containers. For example a known process comprises coating polyvinylidene chloride or similar gas-barrier resins on the outer and inner surface of PET containers, and U.S. Pat. No. 4,980,211 discloses a multilayered structure of 2 to 5 layers utilizing a saponified ethylene-vinyl acetate copolymer. These processes however have disadvantages that additional equipment for coating or making multilayered container is required besides conventional molding and forming machines for polyesters and that the use of different polymers leads to readily delamination, with multilayered containers, or difficulty in the recovery or disposal by incineration of used containers. Japanese Patent Publication No. 33618/1978 and U.S. Pat. No. 4,398,642 propose a process which comprises producing containers from a composition obtained by previously blending polyester with nylon or like resins. Although the process enables containers to be produced with existing equipment, the obtained containers suffer a decrease in mechanical properties and have a disadvantage in recovery and re-use.
The use of what is known as thermotropic liquid crystal polymers, which are capable of forming optically anisotropic melt phase, has been proposed in recent years (See, for example, Japanese Patent Application Laid-opens Nos. 192762/1986, 119265/1987, 187033/1987, 45242/1989 and 288421/1 989). Also, Polym. Prepr. (Am. Chem. Soc., Div. Polym. Chem. ), 30 (1), 3-4 (1989) reports that the thermotropic liquid crystal polymer obtained from 40 mol % polyethylene terephthalate and 60 mol % of 4-acetoxybenzoic acid gives a melt-extruded film having an oxygen permeability of 36 ml . 20 μm/m 2 .day.atm. Further U.S. Pat. Nos. 3,778,410 and 3,804,805 disclose a process for producing a copolyester, which comprises reacting a polyester comprising repeating units represented by the formula --OC--R 1 --CO--O--R 2 --O-- wherein R 1 represents a divalent alicyclic radical having 4 to 20 carbon atoms, a divalent aliphatic radical having 1 to 40 carbon atoms or a divalent aromatic radical having 6 to 16 carbon atoms with carbonyl linkages separated by at least 3 carbon atoms, and R 2 represents a divalent aliphatic radical having 2 to 40 carbon atoms, a divalent alicyclic radical having 4 to 20 carbon atoms, a divalent aromatic radical having 6 to 20 carbon atoms or a divalent poly(alkylene oxide) radical having a molecular weight of 200 to 8,000; with an acyloxy aromatic carboxylic acid. These USP's mention substantially only acyloxy benzoic acids as examples of the acyloxy aromatic carboxylic acid.
However, the use of thermotropic liquid crystal polymers so far proposed for molding or forming shaped articles that act as gas-barrier materials has the following two principal problems.
Firstly, shaped articles obtained from thermotropic liquid crystal polymers so far proposed generally have high degree of crystallinity, large anisotropy in mechanical properties and low elongation, whereby their stretching is substantially impossible. It is very difficult to process these polymers into various gas-barrier shaped articles, such as film, sheet, bottles, cups, trays and bags.
To overcome the problem, Japanese Patent Application Laid-open No. 187033/1987 proposes a laminated and stretched shaped article comprising a layer of a thermotropic liquid crystal polyester and, on at least one surface thereof, a layer of polyester comprising polyethylene terephthalate component. The application discloses, with respect to the thickness ratio between the polyester (not exhibiting optical anisotropy) layer and the layer of the thermotropic liquid crystal polyester, that the thickness of the polyester layer is 50 to 98% of the total thickness of the laminated and oriented shaped article and that of the thermotropic liquid polyester layer is 2 to 50%, preferably 5 to 20% on the same basis, and describes that with a thickness of the thermotropic liquid crystal polyester exceeding 50% it is more difficult to stretch the laminated article than is the case with the usual polyester alone. Thermotropic liquid crystal polyesters having small anisotropy in mechanical properties have been also proposed. For example Japanese Patent Application Laid-open No. 28428/1985 discloses a thermotropic liquid crystal polyester comprising terephthaloyl units, 1,3-dioxyphenylene units and 2-substituted-1,4-dioxyphenylene units. Introduction of isoskeleton and substituents as in this proposal tends to improve processability of thermotropic liquid crystal polymer and to render it more ready, although not sufficient, to produce various shaped articles from the resulting polymers.
The second problem that arises when thermotropic liquid crystal polymers so far proposed are used for molding or forming gas barrier shaped articles is that these polymers are not always molded or formed into shaped articles having sufficient gas barrier properties. See, for example, the oxygen permeability of 36 ml . 20 μm/m 2 .day.atm described in the afore-mentioned Polym. Prepr. (Am. Chem. Soc., Div. Polym. Chem.), 30 (1), 3-4 (1989), for a film of the thermotropic liquid crystal polymer obtained from 40 mol % of polyethylene terephthalate and 60 mol % of 4-acetoxybenzoic acid. This film cannot be said to be a high gas barrier material. Further a study made by the present inventors has revealed that films obtained from the thermotropic liquid crystal polyester described in Japanese Patent Application Laid-open No. 28428/1985 do not have a sufficiently high oxygen barrier property.
Japanese Patent Application Laid-open No. 68813/1987 discloses a copolyester obtained by reacting an acetoxy aromatic carboxylic acid mixture comprising p-acetoxybenzoic acid and 6-acetoxy-2-naphthoic acid with polyethylene terephthalate or polybutylene terephthalate, and describes that the product has higher flexural strength, flexural modulus and thermal deformation temperature than products obtained by reacting p-acetoxybenzoic acid alone as the acetoxy aromatic carboxylic acid to be used. This application however does not describe any packaging material or container comprising said copolyester, or teach that said copolyester has high gas barrier property, formability (stretchability), low temperature fluidity and similar excellent characteristics.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a novel thermotropic liquid crystal polyester having excellent formability and excellent gas barrier properties in shaped articles therefrom, in particular excellent oxygen gas barrier property.
Another object of the present invention is to provide a shaped article having high gas barrier property and comprising the above novel thermotropic liquid crystal polyester.
Still another object of the present invention is to provide a packaging material and container having high gas barrier properties.
These objects as well as other objects and advantages of the present invention will become apparent to those skilled in the art from the following description.
One of the above objects is achieved by providing a novel thermotropic liquid crystal polyester consisting essentially of a structural unit (1) represented by the following formula ##STR3## wherein Ar represents a 1,4-phenylene group or 2,6-naphthylene group; a structural unit (2) represented by the following formula
--O--CH.sub.2 CH.sub.2 --O--
and a structural unit (3) represented by the following formula ##STR4## ; said structural units (1) and (2) being contained in substantially the same moles, the sum of said structural units (1) and (2) contained being 15 to 90 mol % and said structural unit (3) being contained in an amount of 10 to 85 mol % [hereinafter this thermotropic liquid crystal polyester is sometimes referred to as "thermotropic liquid crystal polyester (A)"]; or a novel thermotropic liquid crystal polyester consisting essentially of a structural unit (4) represented by the following formula ##STR5## , the above structural unit (2), the above structural unit (3) and a structural unit (5) represented by the following formula ##STR6## , said structural units (4) and (2) being contained in the same moles, the sum of said structural units (4) and (2) being 15 to 90 mol %, the sum of said structural units (3) and (5) being 10 to 85 mol % and the ratio of said structural unit (3) to the sum of said structural units (3) and (5) being at least 10 mol % [hereinafter this thermotropic liquid crystal polyester is sometimes referred to as "thermotropic liquid crystal polyester (B) "].
Another one of the above objects is achieved by providing a shaped article comprising the above thermotropic liquid crystal polyester (A) or (B).
Still another one of the above objects is achieved by providing a packaging material and container comprising at least one polyester selected from the group consisting of the above thermotropic liquid crystal polyester (A), the above thermotropic liquid crystal polyester (B) and a polyester consisting essentially of a structural unit (6) represented by the following formula ##STR7## , the above structural unit (2 ) the above structural unit (3 ) and the above structural unit (5 ), said structural unit (6) and said structural unit (2) being contained in substantially the same moles, the sum of said structural units (6) and (2) being 15 to 90 mol %, the sum of said structural units (3) and (5) contained being 10 to 85 mol %, and the ratio of said structural unit (3) to the sum of said structural units (3) and (5) being at least 10 mol % [hereinafter this polyester is sometimes referred to as "polyester (C) "].
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The structural unit (1) of the thermotropic liquid crystal polyester (A) of the present invention is derivable from an aromatic dicarboxylic acid and is, concretely, terephthaloyl group and/or naphthalene-2,6-dicarbonyl group. The structural unit (4) of the thermotropic liquid crystal polyester (B) of the present invention is naphthalene-2,6-dicarbonyl group. The structural unit (6) of the polyester (C) is terephthaloyl group. Part of the structural unit (1), (4) or (6), preferably not more than 20 mol % of the foregoing may be replaced by other dicarboxylic acid component. Examples of the other dicarboxylic acid component are units derivable from isophthalic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid and like dicarboxylic acids. Further, part of structural unit (1), (4) or (6) can be replaced by a structural unit derivable from a multi-valent carboxylic acid such as trimellitic acid, trimesic acid or pyromellitic acid within an amount that assures melt-processability of the resulting polyester.
The structural unit (2) in the thermotropic liquid crystal polyester (A), thermotropic liquid crystal polyester (B) and polyester (C) is ethylenedioxy group, part of which, preferably not more than 20 mol % of which, may be replaced by glycol components other than ethylene glycol. Examples of said glycol components are 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol and o-, m- or p-xylylene glycol. Part of the structural unit (2) can be replaced by a structural unit derivable from a polyhydric alcohol such as glycerol, trimethylolpropane, triethylolpropane or pentaerythritol, within an amount that assures melt processability of the resulting polyester.
The structural units (1) and (2) in the thermotropic liquid crystal polyester (A) are, generally, introduced into the thermotropic liquid crystal polyester (A) by utilizing as one of the starting materials the polyester obtained by reaction of a terephthalic acid or its ester-forming derivatives and ethylene glycol as principal components; reaction of 2,6-naphthalenedicarboxylic acid or its ester-forming derivatives and ethylene glycol as principal components; or reaction of a mixture of terephthalic acid and 2,6-naphthalenedicarboxylic acid or their ester-forming derivatives and ethylene glycol as principal components. The structural units (2) and (4) in the thermotropic liquid crystal polyester (B) are, generally, introduced into the thermotropic liquid crystal polyester (B) by utilizing as one of the starting materials a polyethylene naphthalate-based polyester obtained by reaction of 2,6-naphthalenedicarboxylic acid or its ester-forming derivatives and ethylene glycol as principal components. The structural units (2) and (6) in the polyester (C) are, generally, introduced into the polyester (C) by utilizing as one of the starting materials a polyethylene terephthalate-based polyester obtained by reaction of terephthalic acid or its ester-forming derivatives and ethylene glycol as principal components.
The above polyethylene terephthalate, polyethylene naphthalate or their copolymers used in the production of the thermotropic liquid crystal polyester (A), the above polyethylene naphthalate-based polyester used in the production of the thermotropic liquid crystal polyester (B) and the above polyethylene terephthalate-based polyester used in the production of the polyester (C) can be produced by known processes having been established for producing conventional polyesters. The known processes include one which comprises esterifying a dicarboxylic acid with a glycol and then conducting polycondensation and one which comprises conducting transesterification of a dicarboxylate and a glycol and then conducting polycondensation. It sometimes gives good results, to use on this occasion an esterification catalyst, transesterification catalyst, polycondensation catalyst, stabilizer and the like. Known catalysts and stabilizers in the production of conventional polyesters, in particular polyethylene terephthalate, can be used for this purpose. Examples of the catalysts accelerating the above reactions are compounds of metals such as sodium, magnesium, calcium, zinc, manganese, tin, tungsten, germanium, titanium and antimony; and examples of the stabilizers are phosphorus compounds such as phosphoric acid, phosphoric acid esters, phosphorous acid and phosphorous acid esters. There can, as required, be added other additives such as a color, ultraviolet absorber, light stabilizer, antistatic agent, flame retardent and crystallization accelerator. There are no specific restrictions with respect to the degree polymerization of the starting material polyesters used for producing the thermotropic liquid crystal polyester (A), thermotropic liquid crystal polyester (B) or polyester (C), but it is preferred that they have an logarithmic viscosity as measured in a 1/1 by weight mixed phenol/tetrachloroethane mixed solvent at 30° C. of 0.01 to 1.5 dl/g.
The sum of the structural units (1) and (2) in the thermotropic liquid crystal polyester (A), that of the structural units (2) and (4) in the thermotropic liquid crystal polyester (B) and that of the structural units (2) and (6) in the polyester (C) are all within the range of from 15 to 90 mol % and preferably within the range of from 25 to 85 mol %, more preferably within the range of from 30 to 80 mol %.
The structural unit (3) in the thermotropic liquid crystal polyester (A), the thermotropic liquid crystal polyester (B) and the polyester (C) is 6-oxy-2-naphthoyl groups. Part, preferably not more than 10 mol %, of the structural unit (3) may be replaced by other hydroxy carboxylic acid component. Examples of said hydroxy carboxylic acid component are oxynaphthoyl groups such as 7-oxy-2-naphthoyl group, 4-oxy-1-naphthoyl group and 5-oxy-1-naphthoyl group.
The structural unit (5) in the thermotropic liquid crystal polyester (B) and the polyester (C) is p-oxybenzoyl group. Part, preferably not more than 10 mol %, of the structural unit (5) may be replaced by other hydroxy carboxylic acid component. Examples of the other hydroxy carboxylic acid component are oxybenzoyl groups which may be substituted, such as 4-oxybenzoyl group, 4-oxy-3-chlorobenzoyl group, 4-oxy-3,5-dimethylbenzoyl group, 4-oxy-3-methylbenzoyl group, and the like.
It is suitable that the structural unit (3) be contained in the thermotropic liquid crystal polyester (A) in an amount of 10 to 85 mol %, preferably 15 to 75 mol %, more preferably 20 to 70 mol %. Melt polymerization becomes difficult, formability is markedly impaired and other troubles occur with a content of the structural unit (3) exceeding 85 mol %, while with the content being less than 10 mol % the obtained polyester does not form thermotropic liquid crystal and its gas barrier property decreases to a large extent, which are not preferred.
In the thermotropic liquid crystal polyester (B) and the polyester (C), it is suitable that the sum of the structural units (3) and (5) be 10 to 85 mol %, preferably 15 to 75 mol %, more preferably 20 to 70 mol %. If the sum exceeds 85 mol %, the melt polymerization will become difficult and the formability of the obtained polyester will be markedly impaired. If the sum is less than 10 mol %, the obtained polyester will exhibit insufficient gas barrier property. It is necessary that the ratio of the structural unit (3) to the sum of the structural units (3) and (5) be at least 10 mol %, which assures the obtained polyester yielding shaped articles having excellent oxygen gas barrier properties.
The structural unit (3) in the thermotropic liquid crystal polyester (A) and the structural units (3) and (5) in the thermotropic liquid crystal polyester (B) and the polyester (C) are, generally, introduced in the polymer molecules by utilizing corresponding acyloxy carboxylic acids as starting materials. Preferred examples of the acyloxy carboxylic acids are acetoxy carboxylic acids obtained by reacting corresponding hydroxy carboxylic acids with acetic anhydride.
The thermotropic liquid crystal polyesters (A) and (B) are capable of forming liquid crystal (i.e. exhibiting optical anisotropy) in the melt phase. The polyester (C) is, in most cases, capable of forming liquid crystal in the melt phase. The optical anisotropy in the melt phase can be confirmed by a method known to those skilled in the art. That is, a specimen foil, preferably one having a thickness of about 5 μm to about 20 μm, is sandwiched between a pair of cover glasses, and observed, while being placed under a crossed nicol and heated at a constant temperature-elevating rate, with a polarization microscope equipped with a heating device for light transmission at a certain temperature or above. To make surer the observation of the transmission of polarized light, a small pressure may be applied at high temperature on the specimen sandwiched between cover glasses, or the top cover glass may be shifted back and forth. The temperature at which polarized light starts transmission in this observation is the transition temperature to an optically anisotropic melt phase. The transition temperature is preferably not higher than 350° C., more preferably not higher than 300° C. from the viewpoint of good melt processability. It is difficult to determine the transition temperature to an optically anisotropic melt phase of the thermotropic liquid crystal polyesters (A) and (B) with a differential scanning calorimeter as used for determining that of conventional thermotropic liquid crystal polyesters. Thus, when differential scanning calorimetry is conducted on the thermotropic liquid crystal polyesters (A) and (B), there often occur the cases where distinct endothermic peak is not observed depending on the monomer contents in the polyesters or, if an endothermic peak is ever observed it is not always based on a transition from crystal to liquid crystal. In the thermotropic liquid crystal polyester (A), the endothermic peak becomes smaller as the content of the structural unit (3) increases and in most cases disappears with the content exceeding 35 mol %. In the thermotropic liquid crystal polyester (B), the endothermic peak becomes smaller as the contents of the structural units (3) and (5) increase and often disappears when the sum of the contents of the structural units (3) and (5) exceeds 35 mol %.
The thermotropic liquid crystal polyester (A) is produced for example by first effecting acidolysis of polyethylene terephthalate, polyethylene naphthalate, a copolymer or mixture of the foregoing with 6-acyloxy-2-naphthoic acid to prepare the desired polyester fragment and then increasing the degree of polymerization of the polyester fragment.
The thermotropic liquid crystal polyester (B) is produced for example by first effecting acidolysis of polyethylene naphthalate-based polyester with 6-acyloxy-2-naphthoic acid and p-acyloxybenzoic acid to prepare the desired polyester fragment and then increasing the degree of polymerization of the polyester fragment. The polyester (C) is produced for example by first effecting acidolysis of polyethylene terephthalate-based polyester with 6-acyloxy-2-naphthoic acid and p-acyloxybenzoic acid to prepare the desired polyester fragment and then increasing the degree of polymerization of the polyester fragment.
In the above processes for the production of the thermotropic liquid crystal polyesters (A) and (B) and the polyester (C), the acidolysis of the first step is generally effected at 250° to 300° C. and under an atmosphere of an inert gas such as nitrogen, argon or carbon dioxide. In most cases, it is preferred to use 6-acetoxy-2-naphthoic acid and p-acetoxybenzoic acid for the 6-acyloxy-2-naphthoic acid and p-acyloxybenzoic acid, respectively.
6-Hydroxy-2-naphthoic acid can be used as a starting material compound instead of 6-acyloxynaphthoic acid in the above process for the production of the thermotropic liquid crystal polyesters (A) and (B) or that of the polyester (C). p-Hydroxybenzoic acid can be used as a starting material instead of P-acyloxybenzoic acid in the above process for the production of the thermotropic liquid crystal polyester (B) or that of the polyester (C). In these cases, the hydroxy carboxylic acid (i.e. 6-hydroxy-2-naphthoic acid and/or P-hydroxybenzoic acid), which is the starting material, is reacted with a lower aliphatic acid anhydride, preferably acetic anhydride, to convert (effect acylation) substantially all the hydroxyl groups to acyloxy groups, preferably acetoxy groups, and the resulting acyl ester is, without being isolated, reacted with a prescribed starting material polyester, to give the desired thermotropic liquid crystal polyester (A), thermotropic liquid crystal polyester (B) or polyester (C). Here the starting material polyester can be added to the reaction system at an optional point time before and after the acylation reaction of 6-hydroxy-2-naphthoic acid and/or p-hydroxybenzoic acid. Where in the production process utilizing a hydroxy carboxylic acid 6-hydroxy-2-naphthoic acid alone or a mixture of 6-hydroxy-2-naphthoic acid and a small amount of p-hydroxybenzoic acid is used, it is preferred to add to the reaction system a solvent, particularly acetic acid, that does not impair the intended acylation reaction and has a boiling point of about 100° C. to about 200° C. for the purpose of preventing deposition in the system of 6-acyloxy-2-naphthoic acid that forms by the acylation, the deposition rendering it difficult to stir the reaction system.
During the acidolysis reaction of 6-acyloxy-2-naphthoic acid or a mixture thereof with p-acyloxybenzoic acid and a starting material polyester, lower aliphatic acids that form are mostly evaporated off from the system. Then, the reaction mixture remaining in the system is heated at 250° to 350° C. in vacuo to evaporate off the lower aliphatic acids and to increase the degree of polymerization of the reaction product to a suitable one, preferably to an logarithmic viscosity of at least 0.1 dl/g, suitable for molding or forming the desired shaped article. Here the polymerization temperature is preferably at least 270° C. in view of reaction rate and not higher than 350° C. to suppress the decomposition of the polyester and more preferably in a range of 270° to 320° C. It is preferred to gradually reduce the pressure at this polymerization stage to eventually not more than 1 mmHg, more preferably not more than 0.5 mmHg. Solid phase polymerization or the like known to those skilled in the art can also be employed to further increase the molecular weight.
The thermotropic liquid crystal polyester (A) or (B) or polyester (C) generally has an logarithmic viscosity as determined in pentafluorophenol at 60° C. of at least 0.1 dl/g and preferably at least 0.3 dl/g, more preferably at least 0.5 dl/g in view of the mechanical property of the obtained shaped articles. Although the inherent viscosity has no critical upper limit, it is preferably not more than 3.0 dl/g, more preferably not more than 2.0 dl/g in view formability and the like.
The contents of the structural units constituting the thermotropic liquid crystal polyesters (A) and (B) and polyester (C) are determined by NMR spectrometry on a solution prepared by dissolving the specimen polyester in an appropriate solvent. The contents thus determined are generally substantially the-same as the ratios of starting materials fed.
The thermotropic liquid crystal polyesters (A) and (B) give, when their melt are rapidly cooled, shaped articles having markedly low degree of crystallinity of generally not more than 20% as determined by X-ray diffraction method, thus differing from known thermotropic liquid crystal polymers. The degree of crystallinity decreases with increasing ratio of the structural units (3) and (5) in the polyester. Shaped articles such as film obtained from the thermotropic liquid crystal polyester (A) or (B) can therefore be heat stretched uniaxially and biaxially, thus being different from thermotropic liquid crystal polyesters so far proposed. In most cases the film can be heat stretched by at least 2×2 times or at least 3×3 times simultaneously or successively. In addition, shaped articles such as film obtained from the thermotropic liquid crystal polyester (A) or (B) are excellent in gas barrier properties both before and after such heat stretching. These characteristic features never develop in those thermotropic liquid crystal polyesters comprising as the hydroxy aromatic carboxylic acid component one from p-hydroxybenzoic acid or its ester-forming derivatives alone or two types of hydroxybenzoic acids or their ester-forming derivatives alone. Shaped articles obtained from the thermotropic liquid crystal polyester (A) or (B) have, in spite of their low degree of crystallinity, markedly high mechanical properties such as flexural strength and flexural modulus than those obtained from thermotropic liquid crystal polyesters so far proposed.
The thermotropic liquid crystal polyesters (A) and (B) can be melt processed into various shaped articles by known processes for conventional polyesters and are particularly suited for forming sheets and films thanks to their capability to be heat-stretched. Hollow shaped articles can also be produced by extrusion blow molding or what is known as direct blowing, injection blow molding, biaxial stretching blow molding or like processes. Films obtained from the thermotropic liquid crystal polyester (A) are transparent when they are thin, and for example most extruded films having a thickness of 25 μm have sufficient transparency. Capability of yielding such transparent films is also the feature of the thermotropic liquid crystal polyester (A) that is never possessed by conventional thermotropic liquid crystal polyesters.
The thermotropic liquid crystal polyester (A) or (B) can be laminated with other polymers, e.g. polyolefin resins such as polyethylene and polypropylene, polyester resins such as polybutylene terephthalate, polyethylene terephthalate and polyethylene naphthalate and polyamide resins such as nylon. Thus, laminated films, sheets, tubes and the like can be produced by co-extrusion, dry lamination, sandwich lamination or like processes, and laminated containers such as cups and bottles can be produced by injection molding, blow molding, biaxially stretching blow molding, vacuum forming, compression molding or like molding or forming processes.
Shaped articles obtained from the thermotropic liquid crystal polyester (A) or (B) have excellent oxygen gas barrier properties, which are 20 to 400 times those of polyethylene terephthalate. Moreover, the excellent oxygen gas barrier properties are very little dependent on humidity. For example, the thermotropic liquid crystal polyesters (A) and (B) each gives a rapidly quenched film having an oxygen permeability of not more than 20 ml . 20 μm/m 2 .day.atm. The oxygen gas barrier property thus initially obtained sometimes increases by heat treating the shaped article.
Accordingly, the thermotropic liquid crystal polyesters (A) and (B) have moldability and formability far improved over conventional thermotropic liquid crystal polyesters and stretchability, as well as excellent oxygen gas barrier properties and are hence used suitably for various packaging materials and containers for which high oxygen barrier properties are required. The thermotropic liquid crystal polyesters (A) and (B) therefore can widely be used for the gas-barrier packaging of for example foods, medicines, cosmetics, textiles, industrial chemicals and the like. The containers or packaging materials comprising the thermotropic liquid crystal polyester (A) or (B) generally have an oxygen permeability as measured on its wall surface at 20° C. of not more than 20 ml.20 μm/m 2 .day.atm.
The term "containers" used herein means shaped articles principally suited for use in packaging foods, medicines and the like, and the "containers" include sheets and films, as well as bottles, trays, cups, bags and like bottomed containers.
Further the thermotropic liquid crystal polyesters (A) and (B) can be used for producing fibers and as coating agents and also, utilizing their low temperature fluidity which is specifically different from conventional thermotropic liquid crystal polyesters, as adhesives and paints.
The thermotropic liquid crystal polyester (C) is produced by a method comprising reacting a polyethylene terephthalate consisting essentially of a structural unit (6) and a structural unit (2), hydroxy aromatic carboxylic acids consisting essentially of 6-hydroxy-2-naphthoic acid and p-hydroxybenzoic acid and a lower aliphatic acid anhydride of from 1.02 to 1.50 mole equivalent based on the hydroxy aromatic carboxylic acids in the presence of solvent at a temperature ranging from 100° C. to 150° C. till the conversion of the hydroxy aromatic carboxylic acids reaches not less than 95 mol % and reacting the obtained reaction mixture at a temperature higher than 150° C.
The polyester (C) is very homogeneous because the contamination to high melting point components such as homopolymer of hydroxy aromatic carboxylic acids can be depressed and sequential randomness of structural units in molecule can be increased. According to said method, the reaction time can be reduced and the polyester (C) having a high degree of polymerization can be obtained easily.
As the lower aliphatic acid anhydride are used preferably anhydride of lower aliphatic acid having 1 to 8 carbon atoms, for example, acetic anhydride, propionic anhydride, monochloroacetic anhydride, dichloroacetic anhydride, trichloroacetic anhydride, succinic anhydride, glutaric anhydride, maleic anhydride, butyric anhydride, valeric anhydride, and so on. In view of price and boiling point preferable in reaction operation, acetic anhydride is used most preferably. The lower aliphatic acid anhydride should be used in an amount of from 1.02 to 1.50 mole equivalent based on the hydroxy aromatic carboxylic acids. Where the amount is below 1.02 mole equivalent, it takes long time to obtain the desired polyester (C), or the degree of polymerization cannot be sufficiently increased. Where the amount is beyond 1.50 mole equivalent, the obtained polyester colors remarkably.
As the solvent is used preferably organic compound which has boiling point of from 100° to 300° C. and solubility of the 6-acyloxy-2-naphthoic acid corresponding to the product obtained from the employed lower aliphatic acid anhydride and 6-hydroxy-2-naphthoic acid as solute at 25° C. being not less than 15 g(solute)/100 g(solvent) and does not have an evil effect on the acylation, acidolysis, and polymerization. The preferable examples of solvent are a lower aliphatic acid such as acetic acid, propionic acid, butyric acid, isobutyric acid, trimethylacetic acid, etc.; aromatic hydrocarbon such as toluene, xylene, pseudocumene, diphenylmethane, biphenyl, diphenyl ether, diphenyl sulfide, diphenyl sulfone, etc. In view of boiling point, price and easiness of recovery, acetic acid is used most preferably. The reaction system should be kept in the condition of suspension or solution in the presence of said solvent so that the system can be sufficiently stirred at least till the system reaches the molten state. From this point of view, solvent is used preferably in an amount of from 0.5 to 5 times by weight based on the hydroxy aromatic carboxylic acids.
In the above method, first, a reaction among the polyethylene terephthalate, hydroxy aromatic carboxylic acids and lower aliphatic acid anhydride is caused in the presence of solvent at 100° to 150° C. At this stage is mainly caused acylation, that is, hydroxy aromatic carboxylic acids react with lower aliphatic acid anhydride to yield the corresponding acyloxy aromatic carboxylic acids. In this acylation reaction, the system should be maintained at a temperature not higher than 150° C. till the conversion of the hydroxy aromatic carboxylic acids reaches not less than 95 mol %. Where the system is at a temperature higher than 150° C. before the conversion of the hydroxy aromatic carboxylic acids is beyond 95 mol %, the acylation reaction proceeds no more and evil effects are produced on the reaction velocity in the following polymerization stage and the degree of the obtained polyester. The reaction time for which the conversion of hydroxy aromatic carboxylic acids reaches 95 mol % is usually from 0.5 to 4 hours, although it changes depending on the reaction conditions such as reaction temperature, etc. The conversion of hydroxy aromatic carboxylic acids can be determined, for example, by measuring the residual amount of unreacted hydroxy aromatic carboxylic acids by high performance liquid chromatography, it can be also determined by 1H-NMR spectrometry. Where solvent is absent in this stage, as acylation reaction proceeds, the produced acyloxy naphthoic acid solidifies and the reaction system becomes heterogeneous remarkably and so the reaction can proceed smoothly no more as the case may be. In such heterogeneous system, acidolysis reaction at a temperature beyond 150° C. does not proceed smoothly as well as acylation reaction, homopolyester of acyloxy naphthoic acid produces remarkably, and the resulting polyester has the inferior randomness and contains high boiling point components. The acylation reaction is preferably carried out in an atmosphere of inert gas such as nitrogen, argon, carbon dioxide, etc. under near atmospheric pressure or higher pressure with stirring.
The reaction mixture obtained in acylation which is carried out at a temperature not higher than 150° C. is subjected to a reaction which is carried out at a temperature beyond 150° C. This reaction consists of acidolysis reaction (the second stage) which is generally carried out at a temperature ranging from 150° to 230° C. under near atmospheric pressure or higher pressure and polymerization reaction (the third stage) which is generally carried out at a temperature ranging from 250° to 350° C. under pressure ranging from atmospheric pressure to reduced pressure.
During the acidolysis reaction, the polyethylene terephthalate is acidolysized mainly by the produced acyloxy aromatic carboxylic acids to yield polyester fragments. The acidolysis reaction is preferably carried out in an atmosphere of inert gas such as nitrogen, argon, carbon dioxide, etc. at a temperature ranging from 150° to 230° C. under pressure from near atmospheric pressure or higher pressure for from 30 minutes to 5 hours with stirring. Controlling the reaction temperature to be not higher than 230° C., the formation of high melting point polyester rich in acyloxy aromatic carboxylic acid components is suppressed, and the obtained polyester becomes more homogeneous. And carrying a reaction at a temperature beyond 150° C. for not shorter than 30 minutes, the acidolysis reaction of the polyethylene terephthalate proceeds sufficiently, the randomness of the obtained polyester is increased, and the resulting polyester has excellent homogeneity and formability.
In the polymerization reaction, it is preferable to increase the temperature from 230° C. to a temperature ranging from 250° to 350° C. with stirring in an atmosphere of inert gas such as nitrogen argon, carbon dioxide, etc. At this temperature increasing stage, the greater part of theoretical amount of the formed lower aliphatic acid is usually evaporated off from the system. And after the reaction temperature reaches a temperature ranging from 260° to 270° C., it is preferable to gradually increase the degree of vacuum up to not higher than 1 mmHg, preferably not higher than 0.5 mmHg finally over a period of at least 1 hour, preferably not less than 2 hours so as to evaporate off the lower aliphatic acid. In this way, it is preferable to increase the degree of polymerization of polyester to a suitable one, preferably to a logarithmic viscosity of at least 0.1 dl/g. As the polymerization temperature under such reduced pressure, it is preferable to employ a temperature of at least 270° C. in view of reaction velocity and to employ a temperature of not higher than 350° C. in view of suppressing decomposition of the produced polyester. It is most preferable to employ a temperature ranging from 270° to 320° C.
The polyester (C) is, different from other known thermotropic liquid crystal polyesters, excellent in heat processability and hence desirably used for packaging materials and containers having various shapes, which, although sometimes inferior to those obtained from the thermotropic liquid crystal polyester (A) or (B), have a gas barrier property of markedly high level. For example containers or packaging materials comprising the polyester (C) generally have an oxygen permeability as measured on its wall surface at 20° C. of not more than 20 ml . 20 μm/m 2 .day.atm. These containers or packaging materials thus have oxygen gas barrier properties 20 to 400 times as high as those from polyethylene terephthalate. Thanks also to a very small humidity dependency of its oxygen gas barrier properties, the polyester (C) is suitably used for packaging materials and containers for which high oxygen gas barrier properties are required. These packaging materials and containers are therefore widely used for gas-barrier packaging of for example foods, medicines, cosmetics, textiles, industrial chemicals and the like.
Containers and packaging materials comprising the polyester (C) can be obtained, utilizing the above-described excellent processability of the polyester, by injection molding, blow molding, biaxial stretching blow molding, vacuum forming, compression molding or like molding or forming processes. The containers and packaging materials can be of various shapes including trays prepared from sheets by vacuum or pressure forming, shapes prepared by deep drawing an unstretched sheet, shapes prepared by direct blowing or biaxial stretching blowing parisons obtained by injection molding or parisons prepared by providing a pipe with a bottom, and the like.
The containers or packaging materials comprising the polyester (C) includes, in addition to those formed of the polyester alone, those comprising a blend of the polyester and another resin, comprising multilayered structure comprising layers of other resins and those coated. Examples of the other resins are polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate and polyamide resins such as nylon.
Having generally described this invention, a further understanding can be obtained by reference to certain specific examples which are provided herein for purpose of illustration only and are not intended to be limitative of this invention unless otherwise specified.
Various properties in the Examples were determined by the following methods.
1) Logarithmic viscosity (η inn )
Determined at 60° C. on a 0.1 g/dl solution of specimen in pentafluorophenol.
η.sub.inn =1n (t.sub.1 /t.sub.0)/c
wherein η inn means the ligarithmic viscosity in dl/g, t 0 the flow down time (sec) of the solvent, t 1 that of the specimen solution and c the concentration (0.1 g/dl) of specimen in the solution.
2) Melting point (T m ) and glass transition temperature (T g )
A specimen obtained by rapid quenching of the polyester to test is tested with a differential scanning calorimeter (DSC; TA-3000; made by Mettler) at a temperature elevating rate of 10° C./min.
3) Oxygen gas permeability (PO 2 )
A heat-pressed film, a stretched film or a film laminated with PET and stretched of specimen is tested with a gas transmission rate tester (OX-TRAN 10/50A; made by Modern Control Co.) at 20° C., 0%, 65% (unless otherwise specified) or 100% RH. The results are expressed in ml . 20 μm/m 2 .day.atm.
4) Stretchability
A specimen is formed at 260° to 290° C. into a heat-pressed film having a thickness of about 100 μm. The film is biaxially stretched by 3×3 times at 100° to 240° C. with a biaxially stretching apparatus made by Shibayama Kagaku Kiki Seisakusho Co. The results-of the stretchability evaluated are expressed as:
Good: a uniform biaxially stretched film is obtained; and
Unstretchable: no stretchability is observed and the film tested breaks.
5) Polymer composition
A specimen polymer is dissolved in trifluoroacetic acid and subjected to 500 MHz, 1 H-NMR spectrometry (with JNM GX-500, made by JEOL Ltd.). The compositions obtained by the spectrometry were confirmed to be the same within analysis precision as those of starting materials fed.
Example 1 [Preparation example of thermotropic liquid crystal polyester (A)]
An 8-1 reaction vessel equipped with a stirrer, a distillation column and a nitrogen gas inlet was charged with 975 g (4.0 moles) of a polyethylene naphthalate having an logarithmic viscosity as determined at 30° C. on its solution in a 1/1 by weight mixed phenol/tetrachloroethane solvent of 0.65 dl/g and 1,390 g (6.0 moles) of 6-acetoxy-2-naphthoic acid. The reaction system was substituted three times with nitrogen gas and the contents were heated with stirring at 290° C. for 1 hour with nitrogen gas flowing into the system, and, after the system had gradually been evacuated, reaction was further effected under a pressure of about 30 mmHg for about 2 hours. By this operation, about 90% of theoretical amount of acetic acid was distilled off. The reaction system was further evacuated and reaction was effected under a pressure of 1 mmHg or below for 5 hours, and the product polyester was withdrawn.
The thus obtained polymer was dissolved in trifluoroacetic acid and the solution was subjected to 1 H-NMR spectrometry, to reveal that the ratio of the contents of structural units constituting the polymer, [structural unit (1)+structural unit (2)]/[structural unit (3)], was 57/43, which is substantially the same as the ratio of the amounts of starting materials fed. A minute specimen of the obtained polymer was heated in a heating device for microscope (TH-600; made by Linkam Co.) under a nitrogen atmosphere at a rate of 10° C./min and observed with a polarization microscope and under a crossed nicol. Then, the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 88° C. but no endothermic peak at all. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 8%. Next, a test specimen with a size of 75×15×2 mm was prepared from the polymer with an injection molding machine, TK14-1AP made by Tabata Kikai Co., at a cylinder temperature and mold temperature of 280° C. and 30° C. respectively and under an injection pressure of 800 kg/cm 2 . The test specimen obtained was tested for flexural strength and flexural modulus according to JIS K7203, to give the following results (data in the direction of resin flow).
Flexural strength: 2,138 kg/cm 2
Flexural modulus: 12.9×10 4 kg/cm 2
The polymer was melted and pressed at 280° C. and then rapidly quenched through a water-cooled cooling press to form a film having a thickness of about 100 μm. The film obtained was tested for oxygen gas permeability with a gas transmission tester, OX-TRAN 10/50A made by Modern Control Co. at 20° C. 65% RH to give one of 1.6 ml . 20 μm/m 2 .day.atm. A heat-pressed film having a thickness of about 100 μm and obtained in the same manner was subjected to 3×3 simultaneous biaxial stretching at a temperature of 150° C. through a biaxially stretching machine made by Shibayama Kagaku Kiki Seisakusho Co., to give a uniform film having a thickness of about 10 μm.
The ligarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 2 [Preparation example of thermotropic liquid crystal polyester (A)]
Example 1 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid to 50/50, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 230° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 82° C. and a small endothermic peak at 235° C. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 11%. Next, a test specimen was prepared from the polymer by the same injection molding conditions as in Example 1 and tested for flexural strength and flexural modulus, to give the following results (data in the direction of resin flow).
Flexural strength: 2,046 kg/cm 2
Flexural modulus: 12.1×10 4 kg/cm 2
The inherent viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 3 [Preparation example of thermotropic liquid crystal polyester (A) ]
Example 1 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid to 60/40, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 250° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 80° C. and an endothermic peak at 252° C. Next, injection molding was conducted under the same conditions as in Example 1 and the obtained test specimen was tested for flexural strength and flexural modulus, to give the following results (data in the direction of resin flow).
Flexural strength: 1,844 kg/cm 2
Flexural modulus: 10.8×10 4 kg/cm 2
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 4 [Preparation example of thermotropic liquid crystal polyester (A) ]
Example 1 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid to 70/30, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 93° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity by X-ray wide-angle scattering, to give one of 7%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 5 [Preparation example of thermotropic liquid crystal polyester (A)]
An 8-1 reaction vessel equipped with a stirrer, a distillation column and a nitrogen gas inlet was charged with 1,504 g (8.0 moles) of 6-hydroxy-2-naphthoic acid, 918 g (9.0 moles) of acetic anhydride, 484 g (2.0 moles) of a polyethylene naphthalate having an logarithmic viscosity as determined on its solution in a 1/1 by weight mixed phenol/tetrachloroethane solvent of 0.65 dl/g and 960 g (16.0 moles) of acetic acid as a reaction solvent. The reaction system was substituted three times with nitrogen gas and the contents were heated with stirring and under reflux for 2 hours with nigrogen gas flowing into the system. Thereafter, after the temperature of the system had been elevated up to 290° C. over about 3 hours, the system was gradually evacuated and reaction was further effected under a pressure of about 30 mmHg for about 2 hours. By this operation, about 95% of theoretical value of acetic acid and acetic anhydride was distilled off. The reaction system was further evacuated, and reaction was effected under a pressure of 1 mmHg or below for 1 hour, and the product polyester was withdrawn.
The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 97° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity by X-ray wide-angle scattering, to give one of 9%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 6 [Preparation example of thermotropic liquid crystal polyester (A)]
Example 5 was repeated except for changing the amounts of the starting materials and solvent to 564 g (3.0 moles) for 6-hydroxy-2-naphthoic acid, 367 g (3.6 moles) for acetic anhydride, 360 g (6.0 moles) for acetic acid and 1,694 g (7.0 moles) for the polyethylene naphthalate, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 250° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 122° C. and an endothermic peak at 256° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 7 [Preparation example of thermotropic liquid crystal polyester (A)]
Example 5 was repeated except for changing the amounts of the starting materials and solvent to 376 g (2.0 moles) for 6-hydroxy-2-naphthoic acid, 245 g (2.4 moles) for acetic anhydride, 240 g (4.0 moles) for acetic acid and 1,936 g (8.0 moles) for the polyethylene naphthalate, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 255° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 122° C. and an endothermic peak at 258° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 8 [Preparation example of thermotropic liquid crystal polyester (A)]
Example 1 was repeated except for using instead of the polyethylene naphthalate 4.0 moles of a polyethylene terephthalate having an logarithmic viscosity as determined at 30° C. on a solution in a 1/1 by weight mixed phenol/tetrachloroethane solvent of 0.70 dl/g and changing the polymerization temperature to 280° C., to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 180° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 82° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity by X-ray wide-angle scattering, to give one of 13%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 9 [Preparation example of thermotropic liquid crystal polyester (A)]
Example 3 was repeated except for using instead of the polyethylene naphthalate the same polyethylene terephthalate (6.0 moles) as used in Example 8 and changing the polymerization temperature to 280° C., to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 225° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 80° C. and an endothermic peak at 226° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
Example 10 [Preparation example of thermotropic liquid crystal polyester (A) ]
Example 5 was repeated except for using as starting materials and solvent 1,128 g (6.0 moles) of 6-hydroxy-2-naphthoic acid, 643 g (6.3 moles) of acetic anhydride, 720 g (12.0 moles) of acetic acid, 484 g (2.0 moles) of the polyethylene naphthalate and 384 g (2.0 moles) of the same polyethylene terephthalate as used in Example 8, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 50° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 85° C. but no endothermic peak at all.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 1.
TABLE 1__________________________________________________________________________η.sub.inh T.sub.g T.sub.m PO.sub.2 StretchabilityExample(dl/g) (°C.) (°C.) (ml · 20 μm/m.sup.2 · day · atm) (3 × 3 times)__________________________________________________________________________1 0.65 88 -- 1.6 good2 0.58 82 235 2.0 good3 0.60 80 252 2.0 good4 0.57 93 -- 0.8 good5 1.25 97 -- 0.5 good6 0.69 122 256 5.3 good7 0.71 122 258 9.0 good8 0.68 82 -- 2.6 good9 0.57 80 226 3.1 good10 1.10 85 -- 2.0 good__________________________________________________________________________
Example 11 [Preparation example of thermotropic liquid crystal polyester (B)]
An 8-1 reaction vessel equipped with a stirrer, a distillation column and a nitrogen gas inlet was charged with 975 g (4.0 moles) of a polyethylene naphthalate having an logarithmic viscosity as determined at 30° C. on its solution in a 1/1 by weight mixed phenol/tetrachloroethane solvent of 0.65 dl/g, 1,150 g (5.0 moles) of 6-acetoxy-2-naphthoic acid and 180 g (1.0 mole) of p-acetoxybenzoic acid. The reaction system was substituted three times with nitrogen gas and the contents were heated with stirring at 290° C. for 1 hour with nitrogen gas flowing into the system, and, after the system had gradually been evacuated, reaction was further effected under a pressure of about 30 mmHg for about 2 hours. By this operation, about 90% of theoretical amount of acetic acid was distilled off. The reaction system was further evacuated and reaction was effected under a pressure of 1 mmHg or below for 5 hours, and the product polyester was withdrawn.
The thus obtained polymer was dissolved in trifluoroacetic acid and the solution was subjected to 1 H-NMR spectrometry, to reveal that the ratio of the contents of structural units constituting the polymer, [structural unit (4)+structural unit (2)]/[structural unit (3)+structural unit (5)], was 57/43, which is substantially the same as the ratio of the amounts of starting materials fed. A minute specimen of the obtained polymer was heated in a heating device for microscope (TH-600; made by Linkam Co.) under a nitrogen atmosphere at a rate of 10° C./min and observed with a polarization microscope and under a crossed nicol. Then, the specimen started to transmit light at a temperature near 160° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 86° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 10%. Next, a test specimen with a size of 75×15×2 mm was prepared from the polymer with an injection molding machine, TK14-1AP made by Tabata Kikai Co., at a cylinder temperature and mold temperature of 280° C. and 30° C. respectively and under an injection pressure of 800 kg/cm 2 . The test specimen obtained was tested for flexural strength and flexural modulus according to JIS K7203, to give the following results (data in the direction of resin flow).
Flexural strength: 2,254 kg/cm 2
Flexural modulus: 13.3×10 4 kg/cm 2
The polymer was melt pressed at 280° C. and then rapidly quenched through a water-cooled cooling press to form a film having a thickness of about 100 μm. The film obtained was tested for oxygen gas permeability with a gas transmission tester, OX-TRAN 10/50A made by Modern Control Co. at 20° C, 65% RH, to give one of 1.2 ml . 20 μm/m 2 .day.atm. A heat-pressed film having a thickness of about 100 μm and obtained in the same manner was subjected to 3×3 simultaneous biaxial stretching at a temperature of 150° C. through a biaxially stretching machine made by Shibayama Kagaku Kiki Seisakusho Co., to give a uniform film having a thickness of about 10 μm.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 2.
Example 12 [Preparation example of thermotropic liquid crystal polyester (B)]
Example 11 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid to 40/30/30, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, and found to show a glass transition temperature at 81° C. but no endothermic peak at all. The polymer was also tested for degree of crystallinity in the same manner as in Example 11, to be found to have one of 11%. Injection molding was next conducted under the same conditions as in Example 11 and the obtained specimen was tested for flexural strength and flexural modulus, to give the following results (data in the direction of resin flow).
Flexural strength: 2,134 kg/cm 2
Flexural modulus: 12.7×10 4 kg/cm 2
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 2.
Example 13 [Preparation example of thermotropic liquid crystal polyester (B)]
Example 11 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid to 40/10/50, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then the specimen started to transmit light at a temperature near 140° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 75° C. but no endothermic peak at all. The polymer was tested for degree of crystallinity in the same manner as in Example 11, to show one of 12%. Injection molding was next conducted under the same conditions as in Example 11 and the obtained test specimen was tested for flexural strength and flexural modulus, to give the following results (data in the direction of resin flow).
Flexural strength: 2,055 kg/cm 2
Flexural modulus: 12.3×10 4 kg/cm 2
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3 simultaneous biaxial stretching) of the pressed film are shown in Table 2.
Example 14 [Preparation example of thermotropic liquid crystal polyester (B)]
Example 11 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid to 30/60/10, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then the specimen started to transmit light at a temperature near 160° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 89° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity in the same manner as in Example 11, to give one of 8%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 2.
Example 15 [Preparation example of thermotropic liquid crystal polyester (B)]
Example 11 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid to 30/35/35, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 80° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity in the same manner as in Example 11, to give one of 10%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 2.
Example 16 [Preparation example of thermotropic liquid crystal polyester (B) ]
Example 11 was repeated except for setting the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid to 30/10/60, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 72° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity in the same manner as in Example 11, to give one of 14%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 2.
Example 17 [Preparation example of thermotropic liquid crystal polyester (B)]
An 8-1 reaction vessel equipped with a stirrer, a distillation column and a nitrogen gas inlet was charged with 1,316 g (7.0 moles) of 6-hydroxy-2-naphthoic acid, 138 g (1.0 mole) of p-hydroxybenzoic acid, 918 g (9.0 moles) of acetic anhydride, 484 g (2.0 moles) of a polyethylene naphthalate having an logarithmic viscosity as determined at 30° C. on its solution in a 1/1 by weight mixed phenol/tetrachloroethane solvent of 0.65 dl/g and 960 g (16.0 moles) of acetic acid as a reaction solvent. The reaction system was substituted three times with nitrogen gas and the contents were heated with stirring at 290° C. under reflux for about 2 hours with nitrogen gas flowing into the system. Thereafter, the system was heated to 290° C. over about 3 hours, then gradually evacuated and subjected to further reaction under a pressure of about 30 mmHg for about 2 hours. By this operation, about 95% of theoretical amount of acetic acid and acetic anhydride was distilled off. The reaction system was further evacuated and reaction was effected under a pressure of 1 mmHg or below for 1 hour, and the product polyester was withdrawn.
The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 160° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 96° C. but no endothermic peak at all. The specimen was also tested for degree of crystallinity in the same manner as in Example 11, to give one of 7%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 2.
Example 18 [Preparation example of thermotropic liquid crystal polyester (B) ]
Example 17 was repeated except for using 564 g (3.0 moles) of 6-hydroxy-2-naphthoic acid, 138 g (1.0 mole) of p-hydroxybenzoic acid, 490 g (4.8 moles) of acetic anhydride, 480 g (8.0 moles) of acetic acid and 1,452 g (6.0 moles) the polyethylene naphthalate, to obtain a polyester.
The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 250° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 78° C. and an endothermic peak at 252° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result stretchability (3×3 , simultaneous biaxial stretching) of the pressed film are shown in Table 2 .
Example 19 [Preparation example of thermotropic liquid crystal polyester (B) ]
Example 17 was repeated except for using 376 g (2.0 moles) of 6-hydroxy-2-naphthoic acid, 138 g (1.0 mole) of p-hydroxybenzoic acid, 367 g (3.6 moles) of acetic anhydride, 360 g (6.0 moles) of acetic acid and 1,694 g (7.0 moles) of the polyethylene naphthalate, to obtain a polyester.
The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 255° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 122° C. and an endothermic peak at 256° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result stretchability (3×3 simultaneous biaxial stretching) of the pressed film are shown in Table 2.
TABLE 2__________________________________________________________________________η.sub.inh T.sub.g T.sub.m PO.sub.2 StretchabilityExample(dl/g) (°C.) (°C.) (ml · 20 μm/m.sup.2 · day · atm) (3 × 3 times)__________________________________________________________________________11 0.62 86 -- 1.2 good12 0.68 81 -- 2.0 good13 0.58 75 -- 3.2 good14 0.64 89 -- 1.3 good15 0.66 80 -- 1.8 good16 0.62 72 -- 3.0 good17 1.15 96 -- 0.5 good18 0.67 78 253 2.3 good19 0.70 122 256 6.3 good__________________________________________________________________________
Comparative Example
Example 1 was repeated except for using p-acetoxybenzoic acid (6 moles) instead of 6-acetoxy-2-naphthoic acid, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 255° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 250° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed no glass transition temperature and only showed an endothermic peak at 258° C. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 27%.
The polymer was melted and pressed at 290° C. and then rapidly quenched with a water-cooled cooling press to form a film having a thickness of about 100 μm. An attempt was made to simultaneously biaxially stretching by 3×3 times the obtained film with a biaxially stretching apparatus made by Shibayama Kagaku Kiki Seisakusho Co. while changing the stretching temperature within a range of from 100° to 240° C. The film could not be stretched at all and broke at any temperature. The heat-pressed film was further tested for oxygen permeability with a gas transmission rate tester, OX-TRAM 10/50A made by Modern Control Co. at 20° C., 65% RH, to give one of 5.8 ml . 20 μm/m 2 .day.atm.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 3.
Comparative Example 2
Example 3 was repeated except for using p-acetoxybenzoic acid (4.0 moles) instead of 6-acetoxy-2-naphthoic acid, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 260° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed no glass transition temperature and only showed an endothermic peak at 263° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 3.
Comparative Example 3
Example 8 was repeated except for using p-acetoxybenzoic acid (6.0 moles) instead of 6-acetoxy-2-naphthoic acid, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 200° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer -was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed no glass transition temperature and only showed an endothermic peak at 205° C. Injection molding was next conducted under the same conditions as in Example 1, to obtain a specimen, which was then tested for flexural strength and flexural modulus, to give the following results (data in the direction of resin flow).
Flexural strength: 970 kg/am 2
Flexural modulus: 8.1×10 4 kg/cm.sup. 2
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 3.
Comparative Example 4
Example 1 was repeated except for changing the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid to 90/10, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. However, the specimen formed no optically anisotropic melt phase at any temperature below 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 123° C. and an endothermic peak at 260° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 3.
Comparative Example 5
A reaction vessel equipped with a stirrer, a distillation column and a nitrogen gas inlet was charged with 166 g (1.0 mole) of terephthalic acid, 100 g (0.52 mole) of resorcinol diacetate and 104 g (0.5 mole) of methylhydroquinone diacetate. The reaction system was substituted three times with nitrogen gas and the contents were heated over 5 hours to 200° to 320° C. with stirring with nitrogen gas flowing into the system, whereby about 90% of theoretical amount acetic acid was distilled off. The reaction system was further evacuated and reaction was effected under a pressure of 1 mmHg or below for 1 hour, and the product polyester was withdrawn.
The obtained polymer was observed with the same apparatus as used in Example 1 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 200° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 127° C. and an endothermic peak at 200° C. The specimen was also tested for degree of crystallinity by X-ray wide-angle scattering, to give one of 10%.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 3.
Comparative Example 6
The same polyethylene naphthalate as used in Example 1 alone was analyzed by DSC in the same manner as in Example 1, and a pressed film was prepared therefrom and evaluated for oxygen permeability and stretchability in the same manner as in Example 1. The results are shown in Table 3.
Comparative Example 7
The same polyethylene terethalate as used in Example 6 alone was analyzed by DSC in the same manner as in Example 1, and a pressed film was prepared therefrom and evaluated for oxygen permeability and stretchability in the same manner as in Example 1. The results are shown in Table 3.
Comparative Example 8
Example 11 was repeated except for changing the moles ratio of polyethylene naphthalate/6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid to 90/5/5, to obtain a polyester. The obtained polymer was observed with the same apparatus as used in Example 11 under a crossed nicol. However, the specimen formed no optically anisotropic melt phase at any temperature below 350° C. The polymer was analyzed by DSC in the same manner as in Example 11, to be found to show a glass transition temperature at 123° C. and an endothermic peak at 260° C.
The logarithmic viscosity and results by DSC of this polymer and the oxygen permeability and evaluation result of stretchability (3×3 simultaneous biaxial stretching) of the pressed film are shown in Table 3.
TABLE 3__________________________________________________________________________η.sub.inh T.sub.g T.sub.m PO.sub.2 StretchabilityComp. Ex.(dl/g) (°C.) (°C.) (ml · 20 μm/m.sup.2 · day · atm) (3 × 3 times)__________________________________________________________________________1 0.58 -- 258 5.8 unstretchable2 0.64 -- 263 7.5 unstretchable3 0.60 -- 205 16.3 unstretchable4 0.68 123 260 59.0 good5 0.55 127 200 71.0 unstretchable6 -- 123 272 70.0 good7 -- 80 252 175 good8 0.68 123 260 59.0 good__________________________________________________________________________
Examples 20 through 22 and Comparative Examples 9 and 10 [Preparation examples of stretched film]
The pressed films obtained in Examples 1 to 3 and Comparative Examples 6 and 7 were each simultaneously biaxially stretched by 3×3 times at a temperature of 100° to 240° C. and then heat set at a temperature of 120° to 200° C. for 15 minutes, to give biaxially stretched films . The oxygen permeabilities of the obtained films are shown in Table 4.
TABLE 4______________________________________ PO.sub.2 of stretched film Pressed film used (ml · 20 μm/m.sup.2 · day · atm)______________________________________Example 20 Film of Example 1 1.7Example 21 Film of Example 2 1.0Example 22 Film of Example 3 1.0Comparative Film of Compara- 20Example 9 tive Example 6Comparative Film of Compara- 70Example 10 tive Example 7______________________________________
Examples 23 through 26 and Comparative Examples 17 through 13 [Preparation example of laminated and stretched films]
Multilayered sheets were prepared by using the thermotropic liquid crystal polymers obtained in Examples 1, 8, 11 and 12 and a PET resin having an intrinsic viscosity as determined at 30° C. in a 1/1 by weight mixed solvent of phenol/tetrachloroethane of 0.75 dl/g. Thus, each one of the thermotropic liquid crystal polyesters and the PET resin were vacuum-dried at 80° C. and 150° C. respectively for 1 full day and then co-extruded through two extruders to give a PET/thermotropic liquid crystal polyester/PET 3-layer sheet. Each layer of the PET/thermotropic liquid crystal polyester/PET of the obtained sheets had a thickness of 280 μm/20 μm/200 μm. The multilayered sheets thus obtained were simultaneously biaxially stretched by 3×3 times at a temperature of 100° to 120° C. through the biaxially stretching apparatus as used in Example 1, to give stretched films (Examples 23 through 26).
Attempts were made to form the same 2 kinds/3 layers PET/thermotropic liquid crystal polyester/PET film as above using the thermotropic liquid crystal polyester obtained in Comparative Example 1 or that in Comparative Example 3. In both cases, a good film could not be obtained because the intermediate layer (thermotropic liquid crystal polyester layer) could not be stretched (Comparative Examples 11 and 12).
A single-layer sheet having a thickness of about 500 μm was prepared using the PET resin alone and through one of the above extruders. The obtained sheet was simultaneously biaxially stretched by 3×3 times with the above biaxially stretching apparatus at 120° C., to give a stretched film (Comparative Example 13).
These films were evaluated for gas barrier property by the afore-described method. The results are shown in Table 5.
TABLE 5______________________________________ Thermotropic PO.sub.2 of laminated liquid crystal and stretched film polymer used (ml · 20 μm/m.sup.2 · day · atm)______________________________________Example 23 Polymer of 31.8 Example 1Example 24 Polymer of 45.9 Example 8Example 25 Polymer of 25.2 Example 11Example 26 Polymer of 37.9 Example 12Comparative Polymer of Com- Could not be formedExample 11 parative Example 1Comparative Polymer of Com- Could not be formedExample 12 parative Example 3Comparative -- 150Example 13______________________________________
Example 27 [Preparation example of thermotropic liquid crystal polyester (C)]
An 8-1 reaction vessel equipped with a stirrer, a distillation column and a nitrogen gas inlet was charged with 1,316 g (7.0 moles) of 6-hydroxy-2-naphthoic acid(HNA), 138 g (1.0 mole) of p-hydroxybenzoic acid(HBA), 918 g (9.0 moles) of acetic anhydride, 384 g (2.0 moles) of a polyethylene terephthalate(PET) having an intrinsic viscosity as determined on its solution in a 1/1 by weight mixed phenol/tetrachloroethane solvent of 0.70 dl/g and 960 g (16.0 moles) of acetic acid as a reaction solvent. The reaction system was substituted three times with nitrogen gas and the contents were heated with stirring at 130° C. under reflux for about 2 hours with nitrogen gas flowing into the system. Thereafter, the system was heated with stirring at 230° C. for about 2 hours, then heated with stirring to 270° C. over about 2 hours, then gradually evacuated and subjected to further reaction under a pressure of about 30 mmHg for about 2 hours. By this operation, about 95% of theoretical amount of acetic acid and acetic anhydride was distilled off. The reaction system was further evacuated and reaction was effected under a pressure of 1 mmHg or below for 1 hour, and the product polyester was withdrawn.
The condition of reaction system was suspension-like until the temperature of the system was raised up to 270° C., afterward, was shifted into molten state with the evolution of acetic acid. So, smooth stirring was achieved throughout all reaction processes.
The thus obtained polymer was dissolved in pentafluoro-phenol and the solution was subjected to H-NMR and C-NMR spectrometries, to reveal that the ratio of the contents of structural units constituting the polymer, structural unit (6)/structural unit (2)/structural unit (3)/structural unit (5) was 16.9/16.6/58.1/8.4, which is substantially the same as the ratio of the amounts of starting materials fed.
The minute specimen of the obtained polymer was heated in a heating device for microscope (TH-600; made by Linkam Co.) under a nitrogen atmosphere at a rate of 10° C./min and observed with a polarization microscope and under a crossed nicol. Then, the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 95° C. but no endothermic peak at all. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 10%.
Next, the polymer was melted and pressed at 280° C. and then rapidly quenched through a water cooled cooling press to form a film having a thickness of about 100 m. The film obtained was tested for oxygen gas permeability with a gas transmission tester, OX-TRA/10/5OA made by modern Control Co. at 20° C., 65% RH, to give one of 0.4 ml 20 m/m day atm.
A heat-pressed film having a thickness of about 100 m and obtained in the same manner was subjected to 3×3 simultaneous biaxial stretching at a temperature of 160° C. through a biaxially stretching machine made by Shibayama Kagaku Kiki Seisakusho Co., to give a uniform film having a thickness of about 10 m.
Example 28 [Preparation example of thermotropic liquid crystal polyester (C)]
Example 27 was repeated except for setting the molar ratio of 6-hydroxy-2-naphthoic acid/p-hydroxybenzoic acid/polyethylene terephthalate to 60/10/30, to obtain a polyester.
The analysis of the polyester using NMR spectrometries revealed that the ratio of the contents of structural units constituting the polymer, structural unit (6)/structural unit (2)/structural unit (3)/structural unit (5) was 23.5/23.3/45.8/7.4, which is substantially the same as the ratio of the amounts of starting materials fed.
The obtained polymer was observed with the same apparatus as used in Example 27 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 86° C. but no endothermic peak at all. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 8%.
The inherent viscosity and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 6.
Example 29 [Preparation example of thermotropic liquid crystal polyester (C)]
Example 27 was repeated except for setting the mole ratio of 6-hydroxy-2-naphthoic acid/p-hydroxybenzoic acid/polyethylene terephthalate to 50/10/40, to obtain a polyester.
The analysis of the polyester using NMR spectrometries revealed that the ratio of the contents of structural units constituting the polymer, structural unit (6) structural unit (2)/structural unit (3)/structural unit (5) was 28.5/28.8/35.8/6.9, which is substantially the same as the ratio of the amounts of starting materials fed.
The obtained polymer was observed with the same apparatus as used in Example 27 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 140° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 82° C. but no endothermic peak at all. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 11%.
The inherent viscosity and the oxygen permeability and evaluation result of stretchability (3×3 simultaneous biaxial stretching) of the pressed film are shown in Table 6.
Example 30 [Preparation example of thermotropic liquid crystal polyester (C)]
Example 27 was repeated except for setting the mole ratio of 6-hydroxy-2-naphthoic acid/p-hydroxybenzoic acid/polyethylene terephthalate to 30/30/40, to obtain a polyester.
The analysis of the polyester using NMR spectrometries revealed that the ratio of the contents of structural units constituting the polymer, structural unit (6)/structural unit (2)/structural unit (3)/structural unit (5) was 28.4/28.6/21.2/21.8, which is substantially the same as the ratio of the amounts of starting materials fed.
The obtained polymer was observed with the same apparatus as used in Example 27 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 140° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 76° C. but no endothermic peak at all. The specimen as tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 13%.
The inherent viscosity and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 6.
Comparative Example 14
An 8-1 reaction vessel equipped with a stirrer, a distillation column and a nitrogen gas inlet was charged with 1.610 g (7.0 moles) of 6-acetoxy-2-naphthoic acid (Ac-NHA), 180 g (1.0 mole) of p-acetoxybenzoic acid (Ac-HBA), and 384 g (2.0 moles) of a polyethylene terephthalate (PET) which was used in Example 27.
The reaction system was substituted three times with nitrogen gas and the contents were heated with stirring at 280° C. under nitrogen purge during about 1 hour after which time approximately 90% of theoretical acetic acid had evolved and was distilled off. Then, the reaction system was evacuated and reaction was effected under a pressure of 1 mmHg or below for 5 hours, and the product polyester was withdrawn.
The analysis of the polyester using NMR spectrometries revealed that the ratio of the contents of structural units constituting the polymer, structural unit (6)/structural unit (2)/structural unit (3)/structural unit (5) was 17.1/17.2/57.7/8.0, which is substantially the same as the ratio of the amounts of starting materials fed.
The obtained polymer was observed with the same apparatus as used in Example 27 under a crossed nicol, then, the specimen started to transmit light at a temperature near 150° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapedly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 94° C. and endothermic peak at 205° C. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 17%.
Next, the polymer was melted and pressed at 280° C. and then rapidly quenched through a water-cooled cooling press to form a film having a thickness of about 100 μm. The film obtained was subjected to 3×3 simultaneous biaxial stretching at a temperature of 160° C. through a biaxially stretching machine made by Shibayama Kagaku Kiki Seisakusho Co., to give a film having a thickness of about 10 μm. Thus obtained stretched film contained crystals which measure approximately 10˜20 μm in diameter, and was inferior in surface uniformity.
The inherent viscosity and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 6.
Comparative Example 15
Comparative Example 14 was repeated except for setting the mole ratio of 6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid/polyethylene terephthalate to 50/10/40 to obtain a polyester.
The analysis of the polyester using E spectrometries revealed that the ratio of the contents of structural units constituting the polymer, structural unit (6)/structural unit (2)/structural unit (3)/structural unit (5) was 28.8/28.6/35.4/7.2, which is substantially the same as the ratio of the amounts of starting materials fed.
The obtained polymer was observed with the same apparatus as used in Example 27 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 140° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 80° C. and endothermic peak at 210° C. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 20%.
The inherent viscosity and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 6.
Comparative Example 16
Comparative Example 14 was repeated except for setting the mole ratio of 6-acetoxy-2-naphthoic acid/p-acetoxybenzoic acid/polyethylene terephthalate to 30/30/40 to obtain a polyester.
The analysis of the polyester using NMR spectrometries revealed that the ratio of the contents of structural units constituting the polymer, structural unit (6)/structural unit (2)/structural unit (3)/structural unit (5) was 28.8/28.6/21.4/21.2, which is substantially the same as the ratio of the amounts of starting materials fed.
The obtained polymer was observed with the same apparatus as used in Example 27 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 140° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed a glass transition temperature at 70° C. and endothermic peak at 213° C. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 19%.
The inherent viscosity and the oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film are shown in Table 6.
Comparative Example 17
Comparative Example 15 was repeated except for using p-acetoxybenzoic acid instead of 6-acetoxy-2-naphthoic acid, to obtain a polyester.
The analysis of the polyester using NMR spectrometries revealed that the ratio of the contents of structural units constituting the polymer, structural unit (6)/structural unit (2)/structural unit (5) was 28.8/28.6/42.6, which is substantially the same as the ratio of the amounts of starting materials fed.
The obtained polymer was observed with the same apparatus as used in Example 27 under a crossed nicol. Then, the specimen started to transmit light at a temperature near 200° C., the amount of light transmitted increasing thereafter with temperature, and, eventually, remained forming optically anisotropic melt phase when the temperature reached 350° C. A specimen obtained by rapidly quenching the melt of this polymer was analyzed by DSC at a temperature elevating rate of 10° C./min. The specimen showed an endothermic peak at 205° C. but no apparent glass transition temperature. The specimen was tested for degree of crystallinity by X-ray wide-angle scattering, to be found to have one of 25%.
The inherent viscosity and the oxygen permeability and evaluation result of stretchability (3×3 simultaneous biaxial stretching) of the pressed film are shown in Table 6.
Comparative Example 18
The oxygen permeability and evaluation result of stretchability (3×3, simultaneous biaxial stretching) of the pressed film prepared from polyethylene terephthalate used in Example 27 as starting material, are shown in Table 6. Examples 31 and 32 [Preparation example of laminated and stretched film]
Comparative Examples 19 and 20
A multi-layered sheet was prepared by using the thermotropic liquid crystal polymer obtained in Examples 27 or 28 and a polypropylene resin(PP). Thus, the thermotropic liquid crystal polyester and the polypropylene resin were vacuum-dried at 90° C. for 1 day and then co-extruded through two extruders to give a 3-layer PP/thermotropic liquid crystal polyester/PP sheet. Each layer of the PP/thermotropic liquid crystal polyester/PP of the obtained sheet had thickness of 280 μm/20 μm/280 μm. Thus obtained multi-layered sheet was simultaneously biaxially stretched at 170° C. by 3×3 times through the same biaxially stretching apparatus as used in Example 27 to give a stretched film. (Examples 31 and 32).
Next, the polypropylene resin was vacuum-dried at 90° C. for 1 day and then co-extruded through one extruder to give a single-layer sheet. Thus obtained single-layer sheet was simultaneously biaxially stretched at 170° C. by 3×3 times through the same biaxially stretching apparatus as used in Example 27 to give a stretched film. (Comparative Example 19).
The oxygen permeability of these laminated and stretched films which was tested with the same apparatus as used in Example 1, are shown in Table 7.
Next, stretching of 3-layer PP/thermotropic liquid crystal polyester/PP sheet using thermotropic liquid crystal polyester prepared in Example 27 was tried. However, stretching of middle layer (Thermotropic liquid crystal layer) as not achieved at 140°˜200° C., so good stretched film could not be obtained (Comparative Example 20).
TABLE 6______________________________________ η.sub.inh PO.sub.2 Stretch- (dl/g) (ml · 20 μm/m2 · day · ability______________________________________Example27 1.02 0.4 good28 0.97 1.2 good29 0.92 2.2 good30 0.86 2.6 goodComparativeExample14 0.60 1.1 not good15 0.64 4.1 not good16 0.55 4.7 not good17 0.66 16.3 impossible18 175.0 good______________________________________
TABLE 7______________________________________ Thermotropic liquid crystal PO.sub.2 polyester as used (ml · 20 μm/m.sup.2 · day · atm)______________________________________Example31 TLCP prepared in 10.0 Example 2732 TLCP prepared in 29.7 Example 28ComparativeExample19 -- 250020 TLCP prepared in impossible to mold Comparative Example 17______________________________________
Having now fully described the invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention as set forth herein. | Provided are novel thermotropic liquid crystal polyesters consisting essentially of the following structural units (1), (2) and (3) or those (2), (3), (4) and (5) and shaped articles comprising these polyesters. Also provided are packaging materials and containers comprising the above thermotropic liquid crystal polyesters or a polyester consisting essentially of the following structural units (2), (3), (5) and (6). ##STR1## wherein Ar represents a 1,4-phenylene group or 2,6-naphthylene group ##STR2## | 2 |
BACKGROUND OF THE INVENTION
The invention relates to a pressure foot unit for a sewing machine, in particular, a pressure foot unit which is specially adapted for use with an embroidery sewing machine.
Generally in a sewing machine, the shaft (needle bar) of a sewing needle is connected to an upper shaft which is driven for rotation through a cam or the like, and the sewing needle repeats its elevating motion in synchronism with the rotation of the upper shaft. When the sewing needle is raised to be withdrawn from a fabric, the fabric tends to be lifted by being pulled by the upper thread, thereby disturbing the thread tension. In order to prevent this, it is necessary to hold the fabric in position. In particular, a sewing operation of an embroidery sewing machine takes place while moving the fabric in diverse directions, and accordingly there is a high need to suppress the movement of the fabric during the passage of the needle. For this reason, a pressure foot in the form of a plate is disposed adjacent to the sewing needle of a sewing machine. However, it is necessary to unlock the pressure foot when moving the cloth or fabric, and hence the plate serving as a pressure foot is connected with the needle bar, and repeatedly undergoes an up and down movement through a relatively increased stroke as the sewing needle is being elevated. Hence, when the rotational speed of the upper shaft is increased to accelerate the elevating motion of the sewing needle, sounds are produced by percussion or impact as the pressure foot is being elevated.
A prior art for a pressure foot mechanism of a general sewing machine can be known from U.S. Pat. No. 4,981,094 (Class 235), for example.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide a pressure foot unit which is capable of providing a reliable pressure foot action while allowing a movement of a fabric in any desired direction within a horizontal plane by releasing such action as required and while suppressing the generation of sounds during the operation.
The object is accomplished in accordance with the invention by providing a pressure foot unit for a sewing machine, comprising a pressure foot member (10) disposed adjacent to a sewing needle (1) and elevatably supported by the body of the sewing machine; a plurality of spherical members (15A-15D) rotatably mounted at different positions within the pressure foot member and each disposed partly exposed through the lower surface of the pressure foot member; and elastic members (16A-16D) mounted on the pressure foot member for urging each spherical member downward.
According to another feature of the invention, the pressure foot unit further comprises drive means (20) for driving the pressure foot member for elevating motion; reference position detecting means (30) for detecting the pressure foot member located at a given position; and positioning control means (40) for energizing the drive means to position the pressure foot member as referenced to a position detected by the detecting means, to position the pressure foot member at a first position (P1) during the elevating motion of the sewing needle and during the movement of a fabric, and to position the pressure foot member at a second position (P2) higher than the first position in response to a given release command.
According to a further feature of the invention, the pressure foot unit further comprises drive means (20) for driving the pressure foot member for elevating motion; reference position detecting means (30) for detecting the pressure foot member located at a given position; and positioning control means (40) for energizing the drive means to position the pressure foot member as referenced to a position detected by the detecting means, to position the pressure foot member at a first position (P1) during the elevating motion of the sewing needle, to position the pressure foot member at a third position (P3) higher than the first position by an amount which is substantially on the order of the thickness of the fabric during the movement of the fabric, and to position the pressure foot member at a second position (P2) higher than the third position in response to a given release command.
According to an additional feature of the invention, the positioning control means includes position presetting means (50) which adjust each of the first, the second and the third position.
It is to be understood that numerals or characters appearing in parentheses refer to reference numerals used to designate elements shown in an embodiment to be described later, but that the elements used to practise the invention are not limited to specific form or construction of elements shown in the embodiment.
According to the invention, it is unnecessary to connect the pressure foot member with an elevating mechanism for a sewing needle mechanically, but may be positioned by driving it with independent drive means. A plurality of spherical members are rotatably disposed within the pressure foot member so as to be exposed through the lower surface of the member. These spherical members are urged downward by elastic members, so that when the pressure foot member is located at a pressed position (P1) and the spherical members urge the fabric downward, the fabric is permitted to move in a horizontal direction inasmuch as these spherical members are rotatable. Thus, during the operation of the sewing machine, the pressure foot member assumes its pressed position to press against the fabric while allowing its movement in a horizontal direction. Hence, the need to move the pressure foot member up and down as the sewing needle is elevated is eliminated, thus removing the occurrence of sounds by percussion or impact.
In accordance with another feature of the invention, the positioning control means which positions the pressure foot member operates to position the pressure foot member at a first position (pressed position) during the elevating motion of the sewing needle and during the movement of the fabric, and to position the pressure foot member at a second position (retracted position) higher than the first position in response to a given release command. Accordingly, when the pressure foot member is located at the first position, the fabric may be held in place against movement in vertical direction. However, in response to a given release command, the pressure foot member is raised to its retracted position, whereupon the engagement or disengagement of an embroidery frame or fabric can be easily implemented.
In accordance with a further feature of the invention, the positioning control means which positions the pressure foot member operates to position the pressure foot member at a first position during the elevating motion of the sewing needle, to position the pressure foot member at a third position higher than the first position during the movement of the fabric, and to position the pressure foot member at a second position higher than the third position in response to a given release command. Specifically, when the pressure foot member is located at its first position, the fabric can be held against movement, while when the pressure foot member is located at its third position where it is disposed above the first position by an amount which corresponds to the order of thickness of the fabric, any constraint exerted upon the fabric is released, allowing the fabric to be freely moved in a horizontal direction. When the pressure foot member is located at its third position, a clearance between the lower surface thereof and the fabric is very small, which is insufficient to allow the engagement or disengagement of an embroidery frame, and which is also unsuitable to perform the engagement or disengagement of the fabric alone. However, the pressure foot member may be raised to its second position by applying a given release command, whereupon the engagement or disengagement of an embroidery frame or fabric can be easily implemented. During the operation of the sewing machine, the pressure foot member repeatedly moves back and forth between the first and the third position, allowing a movement of the fabric when it is located at its third position. Since a distance between the first and the third position is relatively small, the stroke travelled by the pressure foot member during such reciprocating motion is reduced and does not require a high speed movement, thus suppressing the generation of sounds of percussion or impact caused by such movement.
In accordance with an additional feature of the invention, position presetting means may be used, and each of the first, the second and the third position may be adjusted. Accordingly, the first position may be adjusted to provide an optimum pressing force in accordance with the thickness of a fabric. The third position may be adjusted in accordance with the thickness of the fabric so that the pressing force is positively released at the second position while minimizing the stroke travelled by the pressure foot member. The second position may be adjusted in accordance with the height of an embroidery frame so as to facilitate its engagement and disengagement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing the appearance of an embroidery machine according to an embodiment;
FIG. 2 is a cross section, to an enlarged scale, of a portion of the machine around a needle shown in FIG. 1;
FIG. 3 is an enlarged bottom view as viewed in the direction of the line III--III shown in FIG. 2;
FIG. 4 is a block diagram of an electrical arrangement of the embroidery machine;
FIG. 5 is a flow chart for a microcomputer shown in FIG. 4;
FIG. 6 is a flow chart of a standby processing shown in FIG. 5;
FIG. 7 is a cross section of parts located around the needle shown in FIG. 1 when it assumes a retracted position;
FIG. 8 is a flow chart illustrating the operation of another embodiment;
FIG. 9 is a flow chart of the standby processing for the embodiment shown in FIG. 8; and
FIG. 10 is a cross section of parts located around the needle shown in FIG. 1 when it assumes a released position.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The appearance of an overall embroidery machine according to an embodiment is shown in FIG. 1. The embroidery machine is provided with six sewing needles 1, one of which is selected by a needle selector, which is known in the art, and is positioned directly above a needle hole 8a formed in a throat plate 8 before it is driven for elevating motion to perform a sewing operation. An embroidery frame 12 which is formed so as to surround the needle hole 8a is driven in the directions of X- and Y-axes in a horizontal plane when the sewing needle 1 is located about it in order to bring a next desired stitch position of a fabric supported thereby to the position of the needle hole 8a. In actuality, a mechanism associated with a pressure foot is disposed above the needle hole 8a, but is omitted from illustration in FIG. 1 for ease of illustration of other parts.
A pair of bobbin bases 81L and 81R, on which thread bobbins are placed, are mounted on a machine arm on the both sides thereof. Four bobbins may be normally mounted on each of the bobbin bases 81L and 81R. Each of threads which are taken out of six bobbins out of a total of eight bobbins is passed through a thread tension regulator 82, through an opening in a guide plate and through an opening in a thread take-up lever to be engaged with each of the sewing needles 1.
A specific construction around the needle 1 which is selected and which is positioned directly above the needle hole 8a is shown in FIG. 2a and a view as viewed from the line III--III shown in FIG. 2 is shown to an enlarged scale in FIG. 3. Referring to FIGS. 2 and 3, a needle bar 2 carrying the needle 1 is supported by a frame 3 through a bearing 4 interposed therebetween, and is connected to an upper shaft (not shown) which rotates as driven by a motor of the sewing machine, thus repeating its elevating motion in synchronism with the rotation of the upper shaft. A push bar 5 disposed substantially parallel to the needle bar 2 is supported by the frame 3 through a bearing 6 interposed therebetween, and is vertically movable. A pressure foot 10 is coupled to the lower end of the push bar 5 and is secured thereto by a screw 7.
The pressure foot 10 comprises an arm portion which is coupled to the push bar 5, and a lower retainer foot 10e which is in the form of a ring. The retainer foot 10e is formed with four circular openings 10a, 10b, 10c, 10d in its lower surface, into which coiled compression springs 16A, 16B, 16C and 16D are inserted, with spheres 15A, 15B, 15C and 15D disposed therebelow. To prevent the compression springs 16A-16D and the spheres 15A-15D from being disengaged from the four openings 10a, 10b, 10c and 10d, the lower surface of the retainer foot 10e is covered by a circular plate 11, which is secured thereto by screws 17A, 17B, 17C and 17D. The plate 11 is formed with openings 11a, 11b, 11c and 11d in alignment with the spheres 15A, 15B, 15C and 15D, respectively, each having a diameter slightly less than the diameter of these spheres so that part of the spheres 15A to 15D is exposed through these openings 11a to 11d and projecting below the lower surface thereof. A needle opening 11e is formed centrally in the plate 11.
An electric motor 20, which is a stepping motor in the example shown, for vertically driving the push bar 5 is secured to the frame 3 by a fixture 26 and a screw 27. The motor 20 has a drive shaft on which a screw 21 is mounted and is in meshing engagement with a nut 22. The nut 22 is fixedly mounted on a stud 23 which is engaged with a follower 24. The follower 24 is fixedly mounted on the push bar 5 by means of a screw 25. Accordingly, as the motor 20 is driven, the screw 21 rotates to move the nut 22 in the vertical direction, thereby moving its connected push bar 5 and the pressure foot 10 in the vertical direction.
When the pressure foot 10 is moved down to its pressed position (P1) shown in FIG. 2, a fabric 9 which is placed on the throat plate 8 is urged downward by the compression springs 16A-16D acting through the spheres 15A-15D, and accordingly the fabric 9 can be held against lifting by the force which is produced when the needle 1 is inserted into and withdrawn from the fabric 9. However, under such condition, the spheres 15A-15D can be rotated with a relatively small force applied thereto, and hence can be moved in the directions of X- and Y-axes as the embroidery frame 12 is driven. In other words, there is no need to move the pressure foot 10 up and down as the needle 1 undergoes an elevating motion. However, before the commencement and at the completion of a sewing operation, the pressure foot 10 is raised to its retracted position (P2) shown in FIG. 7 in order to engage and disengage the fabric and the embroidery frame 12.
In order to detect a home position of the push bar 5, a colored annular positioning member 31 is fixedly mounted on an upper portion of the push bar, and an optical sensor of reflection type, acting as a home position sensor 30, is mounted on the frame 3 at a position where it can be disposed opposite to the positioning member 31. Specifically, when the pressure foot 10 is at its lower limit position shown in FIG. 2, the sensor 30 detects the presence of the positioning member 31, and determines this as the detection of the home position. Otherwise, the sensor assumes a non-detection condition. The position of the push bar 5 is detected in terms of a travel from this home position, and the travel is determined on the basis of the number of drive steps of the motor 20.
An electric arrangement of the embroidery machine shown in FIG. 1 is illustrated in FIG. 4. Referring to FIG. 4, a microcomputer 40 is provided for controlling the entire embroidery machine in this example. An operating board 60, a machine drive unit 61, a pressure foot drive unit 62, an embroidery frame drive unit 63, a thread cutter unit 64, a needle selector unit 65, a thread color detector unit 66 and data entry unit 67 are connected to the microcomputer 40. The machine drive unit 61, the embroidery frame drive unit 63, the thread cutter unit 64, the needle selector unit 65, the thread color detector unit 66 and the data entry unit 67 are similarly constructed as conventional ones. The pressure foot drive unit 62 includes the motor 20, its associated driver and the home position sensor 30.
The operating board 50 contains a display 51 capable of displaying various information items and a variety of key switches. The key switches include numerical keys 52, data selection key 53, pressure foot position key 54, UP key 55, DOWN key 56, start key 57, stop key 58, and set key 59. Data selection key 53 is used when selecting one of a plurality of embroidery date items stored on a flexible magnetic disc which is loaded into the data entry unit 67. The pressure foot position key 54 is used for adjustment of the pressed position (P1) and the retracted position (P2) of the pressure foot 10 by a user.
The operation of the microcomputer 40 shown in FIG. 4 is illustrated by a flow chart shown in FIG. 5, and the detail of a standby processing subroutine of FIG. 5 (shown at step 109) is illustrated in FIG. 6. Initially referring to FIG. 5, the overall operation of the embroidery machine will be described. Upon turning on the power supply, an initialization is executed. Specifically, internal memories within the microcomputer 40 itself are initialized, various modes are established and given interrupts are set up, thus bringing the various units connected to the microcomputer 40 to predetermined initial conditions. Then "initialization of pressure foot position" routine is executed, followed by the execution of "initialization of embroidery frame position" routine.
In the "initialization of pressure foot position" routine, while the home position sensor 30 is not detecting a home position at step 102, the motor 20 is driven one step at step 103 to move the pressure foot 10 down. When the pressure foot 10 is moved down to the lower limit position shown in FIG. 2, the sensor 30 detects the home position, whereupon the program proceeds from step 102 to step 104 where the pressure foot 10 is positioned. Under the initial condition, the lower limit position (or home position) is chosen to be the pressed position (P1). At step 104, the content of a pressure foot position counter which is assigned to an internal memory is cleared. The pressure foot position counter is utilized to detect a travel from the home position. At next step 105, the motor 20 is driven one step to raise the pressure foot 10, followed by step 106 where "+1" is added to the content of the pressure foot position counter. At step 107, the content of the pressure foot position counter is examined to see if it matches the value of the retracted position P2. If it does not match, the program returns to step 105, and then the steps 105 and 106 are repeated. This operation is effective to position the pressure foot 10 at its retracted position (P2) shown in FIG. 7.
Subsequent to the initialization of the embroidery frame position indicated at step 108, a standby processing routine indicated by step 109 follows. This routine is repeatedly run until a start command is detected at step 110. Upon detection of the start command, the motor 20 is driven one step at step 111 to move the pressure foot 10 down, and at next step 112, "-1" is added to the content of the pressure foot position counter. At following step 113, the content of the pressure foot position counter is examined to see if it matches the value of the pressed position P1. If no matching is found, the program loops back to step 111, then repeating the steps 111 and 112. If the matching is found, namely, if the pressure foot 10 is positioned at the pressed position P1 (which is equal to the condition shown in FIG. 2 under the initial condition), the program proceeds to step 114.
At step 114, selected embroidery data items are sequentially entered through the data entry unit 67, and the elevating drive of the needle bar 2 is controlled in accordance with such embroidery data at step 115. At step 116, the movement of the embroidery frame is controlled. At step 117, an exchange of the needle 1 is controlled. Such operation is repeatedly executed until the end of the embroidery data is detected at step 118 or until a stop command is detected at step 119. If the end of the embroidery data is detected at step 118 or the stop command is detected at step 119, a thread cutting is performed at step 120, followed by positioning the pressure foot to its retracted position P2 at following step 121.
Referring now to FIG. 6, "standby processing" subroutine will be described in detail. When the "data selection" key on the operating board 50 is depressed, the program proceeds from step 201 to step 202 where "data selection mode" is displayed on the display 51. At step 203, a key entry is waited for. When the numerical key 52 is depressed, a numerical value which corresponds to the operated key is stored in a memory at step 204, and when the "set" key is depressed, the data entry unit 67 is accessed for embroidery data having a number corresponding to the numerical value entered by the numerical key, and such data is retrieved. When embroidery data having a number corresponding to the entered value is not found, an error is displayed at step 208, whereupon the program loops back to step 203. If such data is found, "ready to start" is displayed at step 209, and step 210 waits for the depression of the "start" key. Upon depression of the "start" key, the start flag is set at step 211, whereupon the program returns to the main routine. The start flag is referred to at step 110 in FIG. 5, and if the flag is set, this is interpreted as the presence of the start command.
When the "pressure foot position" key is depressed on the operating board 50, the program proceeds from step 212 to step 213 where "pressure foot position set-up mode" is displayed on the display 51. Then step 214 waits for a key entry. If the numerical key 52 corresponding to "1" is now depressed, the program proceeds to step 216, and if "2" is depressed, the program proceeds to step 217. At step 216, the content of a read-write memory which stores positional information of the pressed position P1 is read out and is stored in a memory of a work area. Similarly, at step 217, the content of a read-write memory storing positional information of the retracted position P2 is read out, and is stored in a memory of a work area. At next following step 218, the positional information (either P1 or P2) stored in the memory of the work area is displayed on the display 51 and then the program waits for a key entry. Upon depression of UP key 55, "+1" is added to the value of the positional information stored in the memory of the work area, while upon depression of DOWN key 56, "-1" is added to the value of positional information stored in the memory of the work area. Upon depression of "set" key 59, the updated value of positional information stored in the memory of the work area is written into a read-write memory which is assigned to positional information of pressed position P1 or retracted position P2, thus updating and registering P1 or P2. Thus, by using the "pressure foot position set-up" mode, a user is allowed to adjust the pressed position P1 or the retracted position P2 as required in accordance with the thickness of the fabric, for example, through an instruction from the operating board 50. It is to be understood that an initial value which is previously stored in ROM is stored into the read-write memory assigned to positional information of the pressed position P1 or retracted position P2 during the initialization.
Another embodiment will now be described. This embodiment remains the same as the embodiment mentioned above except for a modification relating of the processing such as the positioning control, and accordingly, similar parts are designated by like reference characters without repeating their description. An embroidery machine which incorporates this embodiment has the same appearance as shown in FIG. 1, and has an electrical arrangement which remains the same as shown in FIG. 4 except that the operation performed by the microcomputer 40 is modified. The pressure foot mechanism remains the same as before. The operation of the microcomputer 40 according to this embodiment is illustrated in FIGS. 8 and 9, and will now be described with reference to these Figures.
Initially referring to FIG. 8, the detail of "initialization of pressure foot position" remains the same as in the previous embodiment. When a start command is detected at step 110, the motor 20 is driven one step at step 111 to move the pressure foot 10 down. At next step 112, "-1" is added to the content of the pressure foot position counter, and step 113 examines if the content of the counter matches the value of the pressed position P1. If matching is not found, the program returns to step 111 and repeats the steps 111 and 112. When matching is found, or when the pressure foot 10 is positioned at the pressed position P1 (which is equal to the condition shown in FIG. 2 under the initial condition), the program then proceeds to step 114.
At step 114, selected embroidery data is sequentially entered through the data entry unit 67, and at step 115, the elevating motion of the needle bar 2 is controlled in accordance with such embroidery data. Step 116 controls the movement of the embroidery frame while the next following step 117 controls an exchange of the needle 1. When the needle bar 2 is not at its elevated position (where the needle 1 is not engaged with the fabric), the program proceeds from step 131 to step 133, moving the pressure foot to the released position P3 (the condition shown in FIG. 10). Thus, the motor 20 is driven to change the position of the pressure foot 10 until the content of the pressure foot position counter matches P1 (or P3).
Accordingly, in the present embodiment, the fabric is firmly retained in position by the pressure foot when the needle 1 engages and disengages from the fabric, thereby positively preventing a lifting or wandering of the fabric. When a movement of the embroidery frame is required to move the fabric, the pressure foot is slightly raised beforehand to release the pressing force, and hence the possibility that the pressure foot mechanism interferes with a movement of the fabric as the embroidery frame is moved is avoided. The stroke travelled by the pressure foot between the pressed position P1 and the released position P3 is only a slight distance corresponding to the order of the thickness of the fabric, and there is no need to move the pressure foot rapidly. Accordingly, the likelihood of producing sounds of high level as a result of a percussion or impact is prevented.
In the "standby processing" subroutine shown in FIG. 9, it is possible to adjust the released position P3, in the same manner as the positions P1 and P2 are adjusted, by entering "3" from the numerical key during the "pressure foot position set-up" mode. In other respects, the arrangement remains the same as shown in FIG. 6.
As discussed above, in accordance with the invention, there is no need to mechanically connect the pressure foot member with a needle elevating mechanism, but the pressure foot member may be driven and positioned by independent drive means. The pressure foot member internally houses a plurality of spherical means in a rotatable manner which are exposed through the lower surface of the member, and which are urged downward by an elastic member, so that the spherical members remain rotatable to permit a free movement of the fabric in the horizontal direction even when the spherical members presses against the fabric at the pressed position (P1) of the pressure foot member. Thus, during the operation of the sewing machine, the pressure foot member assumes the pressed position where it holds the fabric while allowing it to be movable in a horizontal direction, and hence there is no need to elevate the pressure foot member in accordance with the elevating motion of the needle, thus eliminating the likelihood of producing sounds of percussion or impact.
According to another embodiment of the invention, the positioning control means positions the pressure foot member at a first position (pressed position) during the elevating motion of the needle and during a movement of the fabric, and positions the pressure foot member at a second position (retracted position) higher than the first position in response to a given release command. Specifically, when the pressure foot member is at its first position, the fabric can be held against a vertical movement. When the given release command is applied, the pressure foot member is raised to its retracted position, facilitating the engagement or disengagement of the embroidery frame or fabric.
According to a further feature of the invention, the positioning control means positions the pressure foot member at a first position during the elevating motion of the needle, positions the pressure foot member at a third position higher than the first position during a movement of the fabric, and positions the pressure foot member at a second position higher than the third position in response to a given release command. Thus, when the pressure foot member is at its first position, the fabric can be held against movement. When the pressure foot member is at its third position where it is located by the order of the thickness of the fabric higher than the first position, the force which presses the fabric is released, permitting a free movement of the fabric in the horizontal direction. When the pressure foot member is at its third position, there is a very slight clearance between the lower surface of the pressure foot member and the fabric, which is insufficient to allow the engagement or disengagement of the embroidery frame, and which is also unsuitable to engaging or disengaging the fabric alone. However, by providing a given release command, the pressure foot member may be raised to its second position, where the engagement or disengagement of the embroidery frame or fabric can be easily implemented. During the operation of the sewing machine, the pressure foot member repeatedly moves back and forth between the first and the third position, and the fabric is allowed to move when it assumes the third position. Since the first and the third position are close to each other, the stroke travelled by the pressure foot member for its movement between these positions is reduced and hence need not be driven rapidly, preventing the occurrence of sounds of percussion or impact as it moves.
According to an additional feature of the invention, each of the first, the second and the third position may be adjusted by utilizing position presetting means. Thus, the first position may be adjusted to provide an optimum pressing force in accordance with the thickness of the fabric. The second position may be adjusted in accordance with the thickness of the fabric so as to release the pressing force positively while minimizing the stroke travelled by the pressure foot member. The third position may be adjusted in accordance with the height of the embroidery frame so as to facilitate its engagement and disengagement. | A sound of percussion or impact which is produced as a result of a vertical movement of a pressure foot driven in synchronism with a vertical movement of a sewing needle is eliminated. A sphere 15 exposed through the lower surface of a pressure foot 10 as well as a coiled compression spring 16 which urges the sphere are provided, so that the resilience of the spring is effective to suppress a vertical movement of the fabric while allowing a movement of a fabric 9 in a horizontal plane, thus eliminating the need for a vertical movement of the pressure foot as the needle is driven up and down. Alternatively, an independent drive source may be provided to move the pressure foot in synchronism with the vertical motion of the needle through a minimized stroke. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates generally to a configurable partition that is mobile and interconvertible in configuration. A method and system of use thereof is also disclosed.
[0003] 2. Related Art
[0004] There is a need for an improved partition that offers increased flexibility of use and configurability than existing partition devices and partition systems which overcomes at least one of the aforementioned and possibly other deficiencies, in the art of partitions and partition systems.
SUMMARY OF THE INVENTION
[0005] The present invention provides a device, a method, and a system of use thereof for partitioning areas or spaces which overcomes at least one of the aforementioned deficiencies.
[0006] One general aspect of the present invention provides a device comprising: at least one partition body; at least one motility assembly operably adapted to at least one said partition body; and at least one interconnect, wherein said at least one interconnect is used to interchangeably link said at least one partition body in multiple configurations with another partition body.
[0007] A second general aspect of the present invention provides a method for partitioning space comprising: providing a first partitioning device, wherein said partitioning device includes at least one interconnect, wherein said interconnect is used to interchangeably link said partitioning device body with a second partitioning device body; providing at least a first removably attachable portion on said first partitioning device; removing said removably attachable portion; and replacing said removably attachable portion with a second removably attachable portion, wherein said removably attachable portion is different than said first removably attachable portion.
[0008] A third general aspect of the present invention provides a system for partitioning space comprising: at least one first partitioning device, wherein said partitioning device includes at least one interconnect, wherein said interconnect is used to interchangeably link said partitioning device body with a second partitioning device body; at least a first removably attachable portion on said first partitioning device; and a second removably attachable portion, wherein said removably attachable portion is different than said first removably attachable portion.
[0009] The foregoing and other features and advantages of the invention will be apparent from the following more particular description of embodiments of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Some of the embodiments of this invention will be described in detail, with reference to the following figures, wherein like designations denote like members wherein:
[0011] FIG. 1 depicts a perspective view of a partitioning device, in accordance with the present invention;
[0012] FIG. 2A depicts a face of a first embodiment of a partitioning device, in accordance with the present invention;
[0013] FIG. 2B depicts a face of a second embodiment of a partitioning device, in accordance with the present invention;
[0014] FIG. 2C depicts a face of a third embodiment of a partitioning device, in accordance with the present invention;
[0015] FIG. 2D depicts a face of a fourth embodiment of a partitioning device, in accordance with the present invention;
[0016] FIG. 2E depicts a face of a fifth embodiment of a partitioning device, in accordance with the present invention;
[0017] FIG. 2F depicts a face of a sixth embodiment of a partitioning device, in accordance with the present invention;
[0018] FIG. 3A depicts a cut away end view of a first embodiment of a motility assembly of the device in an extended configuration, in accordance with the present invention;
[0019] FIG. 3B depicts a cut away side view of a first embodiment of the motility assembly of the device in an extended configuration, in accordance with the present invention;
[0020] FIG. 4A depicts a cut away end view of a first embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0021] FIG. 4B depicts a cut away side view of a first embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0022] FIG. 5A depicts a cut away end view of a second embodiment of a motility assembly of the device in an extended configuration, in accordance with the present invention;
[0023] FIG. 5B depicts a cut away side view of a second embodiment of a motility assembly of the device in an extended configuration, in accordance with the present invention;
[0024] FIG. 6A depicts a cut away end view of a second embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0025] FIG. 6B depicts a cut away side view of a second embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0026] FIG. 7A depicts a cut away end view of a third embodiment of a motility assembly of the device in an extended configuration, in accordance with the present invention;
[0027] FIG. 7B depicts a cut away side view of a third embodiment of a motility assembly of the device in an extended configuration, in accordance with the present invention;
[0028] FIG. 8A depicts a cut away end view of a third embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0029] FIG. 8B depicts a cut away side view of a third embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0030] FIG. 9A depicts a cut away end view of a fourth embodiment of a motility assembly of the device in an extended configuration, in accordance with the present invention;
[0031] FIG. 9B depicts a cut away side view of a fourth embodiment of a motility assembly of the device in an extended configuration, in accordance with the present invention;
[0032] FIG. 10A depicts a cut away end view of a fourth embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0033] FIG. 10B depicts a cut away side view of a fourth embodiment of a motility assembly of the device in a retracted configuration, in accordance with the present invention;
[0034] FIG. 11A depicts a cut away end view of a fifth embodiment of the motility assembly of the device in a mobile configuration, in accordance with the present invention;
[0035] FIG. 11B depicts a cut away side view of a fifth embodiment of the motility assembly of the device in a stationary configuration, in accordance with the present invention;
[0036] FIG. 12A depicts a first embodiment of an interconnect of the device, in accordance with the present invention;
[0037] FIG. 12B depicts a second embodiment of an interconnect of the device, in accordance with the present invention;
[0038] FIG. 12C depicts a third embodiment of an interconnect of the device, in accordance with the present invention;
[0039] FIG. 12D depicts a fourth embodiment of an interconnect of the device, in accordance with the present invention;
[0040] FIG. 13A depicts a perspective view of an embodiment of the device including interconnects, in accordance with the present invention;
[0041] FIG. 13B depicts an end view of an embodiment of the device including interconnects, in accordance with the present invention;
[0042] FIG. 13C depicts a side view of an embodiment of the device including interconnects, in accordance with the present invention;
[0043] FIG. 13D depicts another side view of an embodiment of the device including interconnects, in accordance with the present invention;
[0044] FIG. 14 depicts a perspective view of a first embodiment of partitioning devices in use, in accordance with the present invention;
[0045] FIG. 15 depicts a close up view of an embodiment of interconnects of the partitioning device in use, in accordance with present invention;
[0046] FIG. 16 depicts a perspective view of a second embodiment of partitioning devices in use, in accordance with the present invention;
[0047] FIG. 17 depicts a perspective view of a third embodiment of partitioning devices in use, in accordance with the present invention;
[0048] FIG. 18 depicts a perspective view of a fourth embodiment of partitioning devices in use, in accordance with the present invention; and
[0049] FIG. 19 depicts a perspective view of a fifth embodiment of partitioning devices in use, in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0050] Although certain preferred embodiments of the present invention will be shown and described in detail, it should be understood that various changes and modifications may be made without departing from the scope of the appended claims. The scope of the present invention will in no way be limited to the number of constituting components, the materials thereof, the shapes thereof, the relative arrangement thereof, etc., and are disclosed simply as an example of an embodiment. The features and advantages of the present invention are illustrated in detail in the accompanying drawings, wherein like reference numerals refer to like elements throughout the drawings.
[0051] As a preface to the detailed description, it should be noted that, as used in this specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents, unless the context clearly dictates otherwise.
[0052] The present invention offers an improved partitioning device as well as a method and system of use thereof. The present invention offers greater flexibility and more options for configuration than current partitioning devices known in the art. The term partition as used herein denotes a structure, either substantially or partially solid, which separates or divides an area or space into two or more sub-areas or sub-spaces. Partitions can be used, for example, to divide a room having an area into smaller areas.
[0053] For example, the present invention provides for a partition that provides many features including: a capability to attach or interlock two or more partitions together; a capability to attach or interlock two or more partitions together in a plurality of configurations; and a capability to readily move partitions.
[0054] FIG. 1 depicts a perspective view of a partitioning device 5 , in accordance with the present invention. As shown in FIG. 1 , an embodiment of the present invention is a partitioning device 5 comprising: a partition body 10 , a motility assembly 30 , and interconnects 90 . A definition of partition body 10 components follows. In a macroscopic view, a partition body is a three-dimensional form comprised of a plurality of surfaces. Each surface may generally be referred to as a side. A face is a special type of a side. It is a principal, prominent side of a partition body 10 . A side, hereafter, is any secondary side of a partition body 10 . A partition body 10 comprises: at least one face and at least one side. A partition body face typically has a much larger area than a partition body side. As represented in the FIG. 1 embodiment, the body 10 is rectangular in shape forming a cuboid. It should be noted, however, that although the components of the FIG. 1 embodiment are rectangular, partition body shapes may also include but are not limited to other shapes such as triangle, polygons of any number of sides, circle, ellipse, super-ellipse, oval, and combinations thereof. A partition body face 11 A and sides 12 A, 12 B, 12 C, and 12 D, as represented in the FIG. 1 embodiment, may be substantially flat or they may be three dimensional surfaces of any configuration or design. Although not shown in FIG. 1 , it should be apparent that a partition body face exists opposite 11 A. Furthermore, partition body faces and sides, may be comprised of one or more components. Partition body faces and sides may be removably attachable to a partition body.
[0055] In one configuration of a partition body, the partition body faces are made of fabric type materials that may be natural or synthetic. Examples of fabric type materials include but are not limited to polyester, rayon, nylon, sateen, spandex, plastic, cotton, satin, silk, and combinations thereof. Alternatively, the materials used for partition body faces also may include but are not limited to solid type materials that may be natural or synthetic. Examples of solid type materials include but are not limited to steel, aluminum, sheet rock, wood, plexiglass, fiber glass, sound deadening material, nanocomposites, and combinations thereof. The partition body may have for example the partition body faces may be entirely opaque, entirely translucent or any degree of transparency in between. The partition body faces may have surfaces configured to deaden sound. Additionally, partition body faces may be removably replaced with entire partition body faces or subcomponents of different materials, colors, designs, etc. Replacing partition body faces may be done to change the appearance and/or function of the partition body faces. For example, a first partition body face, colored red, may be removed and replaced with a second partition body face, colored green. Likewise, a first partition body face, constructed of wood paneling, may be removed and replaced by a second partition body face, constructed of sound deadening material and having surfaces configured to deaden sound. Typically, partition body faces are about 3 feet by about 6.5 feet. The partition body faces may be any size that allows for the partition body 10 to maintain the capability of dividing an area into a smaller area. FIG. 2A depicts a partition body face 11 B of a partition body 10 , in accordance with the present invention. One embodiment is the partition body 10 having a partition body face 11 B that is cage like in structure. Referring to FIG. 2A , the partition body face 11 B is comprised of parallel slats that substantially span the entire partition body face. Typically, the slats 13 are about 5 inches apart but may be spaced from each other in a range from about 1 inch to about 10 inches. Further, the slats 13 typically are 1 inch in width but may range from about 0.5 inch to about 3 inches in width.
[0056] FIG. 2B depicts a partition body face 11 C of the partition body 10 in accordance with the present invention. One embodiment is the body 10 having the face 11 C that also is cage like in structure. Referring to FIG. 2B , the face 11 C is comprised of parallel slats 13 . The slats 13 do not span the entire partition body face 11 C, but instead stop at some intermediate point. The slats 13 extend from one edge of the partition body face 11 C toward an opposite end a distance from about 0.5 feet to about 3 feet. This configuration of the face 11 C allows from about 4.5 feet to about 2 feet of the face 11 C to be solid like in structure. Alternatively, the slats 13 may begin or end at any location on a partition body face. Typically, the slats 13 are about 5 inches apart but may be spaced from each other in a range from about 1 inch to about 10 inches.
[0057] FIG. 2C depicts a partition body face 11 D of the partition body 10 in accordance with the present invention. One embodiment is the partition body 10 having the face 11 D with circular cutouts 14 distributed throughout. The cutouts 14 may be of any shape or size. Other cutout shapes may be stars, rectangles, triangles, spheroids, or any other decorative or functional shape. In choosing the cutout 14 designs or patterns to be used in a face 11 D, the designs or patterns previously described are not meant to limit the scope of the cutout 14 that may be used in the face 11 D of the partition body 10 . Any cutout 14 design or pattern that can be envisioned and/or reduced to practice may be used in the face 11 D. The size of the cutouts 14 used in a face 11 D typically range from about 5 inches to about 15 inches. The number of cutouts 14 used in the face 11 D ranges from about 2 to about 15 in number. The number and size of the cutouts 14 used in the face 11 D are only limited by the size of the partition face 11 D.
[0058] FIG. 2D depicts a partition body face 11 E of the partition body 10 in accordance with the present invention. One embodiment is the partition body 10 having the partition body face 11 E that is mesh like in structure. Referring to FIG. 2D , the partition body face 11 E is comprised of parallel slats 13 that intersect at a right angle with parallel slats 15 forming spaces 16 . Typically, the slats 13 and 15 are about 5 inches apart, respectively, but may be spaced apart in a range from about 1 inch to about 10 inches. Furthermore, the slats 13 and 15 are typically 1 inch in width but may range from about 0.5 inch to about 3 inches in width.
[0059] FIG. 2E depicts a partition body face 11 F of the partition body 10 in accordance with the present invention. One embodiment is the partition body 10 having the partition body face 11 F that has a rectangular cut out 14 that constitutes a substantial area of the partition body face 11 F. Referring to FIG. 2E , the cut out 14 has dimensions in a range from about 2.5 feet by about 4.5 feet. The dimensions given are not meant to limit the size of the cut out 14 that may be used with the face 11 F. The cut out 14 may range in dimensions between from about 2.5 feet by about 2.5 feet to from about 2.5 feet by about 5.5 feet. This configuration of the face 11 F allows from about 4.5 feet by about 2 feet of the face 11 F to be solid like in structure.
[0060] FIG. 2F depicts a partition body face 11 G of the partition body 10 in accordance with the present invention. One embodiment is the partition body 10 having the partition body face 11 G that has a substantial circular cutout 14 . Referring to FIG. 2F , the face 11 G is comprised of a single cutout 14 . The cutout 14 may by in any shape or size that constitutes a substantial part of the face 11 G. The cutouts 14 may be of any shape or size. Other cutout shapes may be stars, rectangles, triangles, spheroids, or any other decorative or functional shape. In choosing the cutout 14 designs or patterns to be used in a face 11 G, the designs or patterns previously described are not meant to limit the scope of the cutout 14 that may be used in the face 11 G of the partition body 10 . Any cutout 14 design or pattern that can be envisioned and/or reduced to practice may be used in the face 11 G. The size of the cutout 14 used in a face 11 G typically range from about 20% to from about 80% of the area of the face 11 G.
[0061] Referring to FIG. 1 , the dimensions of the sides 12 B and 12 D are typically in range from about 3 inches by about 3.5 feet to about 5 inches by about 5 feet, and the dimensions of the sides 12 A and 12 C are in a range from about 3 inches by about 6 feet to about 5 inches by about 7 feet. At least one of the sides 12 A, 12 B, 12 C, and 12 D is capable of having at least one motility assembly 30 operatively attached or operably integrated into the sides 12 A- 12 D. At least one of the sides 12 A, 12 B, 12 C, and 12 D are capable of functioning as a base for the partition body 10 at any given time.
[0062] As shown in FIGS. 3A , 3 B, 4 A, and 4 B, one embodiment of the present invention focuses on a motility assembly 30 operably integrated within a partition body 10 . The assembly 30 may comprise: a wheel 31 , an axel 32 , an axel mount 33 , a wheel mount 34 , a wheel mount guide 35 , a spring 40 , and a locking mechanism 41 . The wheel 31 may have a diameter from about 2 inches to about 6 inches and a width from about 0.5 inches to about 3 inches. The wheel 31 is centered and rotates about the axel 32 . The axel mount 33 connects the axel 32 with the wheel mount 34 . The wheel mount 34 is further configured to move within the wheel mount guide 35 . The mount guides 35 are operably attached to the partition body 10 . The spring 40 may couple the wheel mount 34 to the wheel mount guide 35 . The spring 40 may be configured to provide a force to extend the wheel 31 out of the partition body 10 and/or to retract the wheel 31 within the partition body 10 . A locking mechanism 41 may be configured to lock the wheel 31 in an extended position out of the partition body 10 and/or in a retracted position within the partition body 10 . The locking mechanism may be released via a lever accessible outside of the partition body 10 . Alternatively, in place of a spring 40 , a lever accessible outside a partition body 10 may be used to apply a force to extend the wheel 31 out of the partition body 10 and/or to retract the wheel 31 within the partition body 5 . Wheel movement is indicated by the direction arrow 37 .
[0063] In the extended configuration (See FIGS. 3A and 3B ), typically the wheel 31 is extended a distance 36 below a partition body 10 side from about 0.5 to about 2.5 inches. In this configuration, a partitioning device may be moved along a surface by simply applying force along the directional arrow 38 . The extended configuration allows a partitioning device to roll across the surface along the directional arrow 38 .
[0064] In the retracted configuration (See FIGS. 4A and 4B ), typically the wheel 31 is retracted a distance 39 above a partition body 10 side from about 0.5 inches to about 2.5 inches. In this configuration, a partitioning device may rest and support itself on a surface using one of the partition body sides. Access between the two configurations is accomplished via the wheel mount guides 35 . The retracted configuration (See FIGS. 4A and 4B ) can be accessed from the extended configuration (See FIGS. 3A and 3B ) by simply applying a force downward along the directional arrow 37 . This causes the wheel mount 34 to move upward along the directional arrow until the wheel 31 is a retracted distance 39 from a partition body 10 side thus accessing the retracted configuration.
[0065] Accessing the extended configuration from the retracted configuration is accomplished by applying an upward force along the directional arrow 37 lifting a partition body 10 side off of the supporting surface. This will cause the wheel mount 34 to automatically move downward within the wheel mount 35 and along the directional arrow 37 until the wheel 31 has been extended a distance 36 below a partition body 10 side. The mechanism of extension and retraction of the wheel 31 is via a pressure loaded spring system within the wheel mount 35 . The spring system reacts to upward and downward forces automatically extending or retracting the wheel 31 . The spring system may have a locking mechanism to hold the wheel 31 in an extended or a retracted position.
[0066] As shown in FIGS. 5A , 5 B, 6 A, and 6 B, one embodiment of the present invention focuses on the assembly 45 operably integrated onto the outside of a partition body 10 face. The assembly 45 may comprise: a wheel 46 , an axel 47 , an axel mount 48 , a wheel mount 49 , wheel mount guides 50 , and axel guides 51 , a spring 56 , and a locking mechanism 57 . The wheel 46 has a diameter from about 2 inches to about 6 inches and a width from about 0.5 inches to about 3 inches. The wheel 46 is centered and rotates about the axel 47 . The axel mount 48 connects the axel 47 with the wheel mount 49 . The wheel mount 49 is further configured to move within the wheel mount guide 50 . The mount guides 50 are operably attached to the partition body 10 . The spring 56 may couple the wheel mount 49 to the wheel mount guide 50 . The spring 56 may be configured to provide a force to extend the wheel 46 below a partition body 10 side and/or to retract the wheel 31 above a partition body 10 side. A locking mechanism 57 may be configured to lock the wheel 46 in an extended position below a partition body 10 side and/or in a retracted position above a partition body 10 side. The locking mechanism may be released via a lever accessible outside of the partition body 10 . Alternatively, in place of a spring 56 , a lever accessible outside a partition body 10 may be used to apply a force to extend the wheel 46 below the partition body 10 side and/or to retract the wheel 46 above a partition body 10 side. Wheel movement is indicated by the direction arrow 52 .
[0067] In the extended configuration (See FIGS. 5A and 5B ), typically the wheel 46 is extended a distance 54 below the partition body 10 side from about 0.5 to about 2.5 inches. In this configuration, a partitioning device may be moved along a surface by simply applying force along the directional arrow 53 .
[0068] In the retracted configuration (See FIGS. 6A and 6B ), typically the wheel 46 is retracted a distance allowing the wheel 46 to be in line with or slightly above a partition body 10 side. In this configuration, a partitioning device may rest and support itself on a partition body 10 side or using the wheels 46 . Access between the retracted and extended configurations may be accomplished via the wheel mount guides 50 and the axel guide 51 . The retracted configuration (See FIGS. 6A and 6B ) can be accessed from the extended configuration (See FIGS. 5A and 5B ) by simply applying a force downward along the directional arrow 52 . This causes the wheel mount 49 to move upward along the directional arrow until the wheel 46 is a retracted distance 54 , to a partition body 10 side, thus accessing the retracted configuration. The axel guide 51 may be a slot that to allow the axel 47 to move upwards along the directional arrow 52 during the retraction and extension steps.
[0069] Accessing the extended configuration from the retracted configuration is accomplished by applying an upward force along the directional arrow 52 lifting a partition body 10 side off of a supporting surface. This will cause the wheel mount 49 to automatically move downward within the wheel mount guide 50 and along the directional arrow 52 until the wheel 46 has been extended a distance 54 below a partition body 10 side. The mechanism of extension and retraction of the wheel 47 may be by a pressure loaded spring system within the wheel mount guide 50 . The spring system may react to upward and downward forces automatically extending or retracting the wheel 46 . The spring system may have a locking mechanism to hold the wheel 46 in an extended or a retracted position.
[0070] As shown in FIGS. 7A , 7 B, 8 A, and 8 B, one embodiment of the present invention focuses on the assembly 60 operably integrated within a partition body 10 . The assembly 60 may comprise: a wheel 61 , an axel 62 , an axel mount 63 , a wheel mount 64 , and a wheel mount guide 65 . The wheel 61 has a diameter from about 5 inches to about 6 inches and a width from about 0.5 inches to about 3 inches. The wheel 61 is centered and rotates about the axel 62 . The axel mount 63 connects the axel 62 with the wheel mount 64 . The wheel mount 64 is further connected to the wheel mount guide 65 . The mount guide 65 is operably attached to the inside of the partition body 10 .
[0071] In the extended configuration (See FIGS. 7A and 7B ), typically the wheel 61 is extended a distance 68 below a partition body 10 side from about 0.5 to about 2.5 inches. In this configuration, a partitioning device may be moved along a surface by simply applying force along the directional arrow 67 . This causes a partitioning device to roll across the surface along the directional arrow 67 .
[0072] In the retracted configuration (See FIGS. 8A and 8B ), typically the wheel 61 is retracted a distance allowing the wheel 61 to be in line with or slightly above a partition body 10 side. In this configuration, a partitioning device may rest and support itself on a partition body 10 side or using the wheel 61 . Access between the extended and retracted configurations is accomplished via the wheel mount guide 65 . The retracted configuration (See FIGS. 8A and 8B ) can be accessed from the extended configuration (See FIGS. 7A and 7B ) by simply applying a force downward along the directional arrow 66 . This causes the wheel mount 65 to move upward along the directional arrow 66 until the wheel 61 is retracted to a partition body 10 side.
[0073] Accessing the extended configuration from the retracted configuration is accomplished by applying an upward force along the directional arrow 66 lifting a partition body 10 side off of a supporting surface. This will cause the wheel mount guide 65 to automatically move downward along the directional arrow 66 until the wheel 61 has been extended a distance 68 below the partition body 10 side. The mechanism of extension and retraction of the wheel 61 is by a reversibly conforming wheel mount guide 65 .
[0074] The wheel mount 65 reacts to upward and downward forces automatically causing the wheel mount guide 65 to conform to one of two shapes. The wheel mount is in an inverted shape, as in FIGS. 7A and 7B , causing the wheel 61 to be in an extended configuration. The wheel mount 65 is in a converted shape, as in FIGS. 8A and 8B , causing the wheel to be in a retracted configuration. The wheel mount 65 is reversibly conformable due to the materials of the wheel mount 65 . The wheel mount 65 may be constructed of materials including but not limited to steel, aluminum, copper, brass, ceramic composites, polymer composites, nano-composites, alloys of the aforementioned, and combinations thereof.
[0075] As shown in FIGS. 9A , 9 B, 10 A, and 10 B, one embodiment of the present invention focuses on the assembly 75 operably integrated on a partition body 10 . The assembly 75 comprises: wheels 76 , axels 77 , axel mounts 78 , wheel swivels 79 , a wheel mount 80 , a wheel mount pin 81 , and a swivel 82 . The wheels 76 have a diameter from about 2 inches to about 6 inches and a width from about 0.5 inches to about 3 inches. The wheels 76 are centered and rotate about the axels 77 . The axel mounts 78 connect the axels 77 with the wheel swivels 79 . The wheel swivels 79 are connected to the wheel mount 80 . The mount 80 is connected to the wheel mount pin 81 which is connected to partition body 10 via the swivel 82 .
[0076] In a first configuration (See FIGS. 9A and 9B ), the assembly 75 extends laterally outwards from the partition body 10 . The wheels 76 are extended a distance 83 from about 3 inches to about 7 inches. In this configuration, a partitioning device may be moved along a surface by simply applying force along a directional arrow 84 . In the first configuration the assembly 75 , specifically the wheels 76 , may be used to assist in stabilizing and/or supporting a partitioning device on the surface.
[0077] In a second configuration (See FIGS. 10A and 10B ), the assembly 75 extends parallel and directly underneath the face 12 A. The wheels 76 are extended a distance 83 from about 3 inches to about 7 inches. In this configuration, the wheels 76 and the entire assembly 75 are out of the way. In the second configuration, a partitioning device may rest and support itself on the surface via the assembly 75 . In the second configuration, a partitioning device may also be moved along a surface by simply applying force along a directional arrow 84 .
[0078] Conversion between the first and second configuration is accomplished via the swivel 82 . The first configuration (See FIGS. 9A and 9B ) can be accessed from the second configuration (See FIGS. 10A and 10B ) by applying a force on the wheel mount 80 . The force causes the wheel mount pin 81 , and subsequently the assembly 75 , to rotate or spin about the swivel 82 . The force may be continuously applied until the assembly 75 is parallel and under a partition body 10 side, see FIGS. 10A and 10B . Continued application of the force may be used to access the first configuration. Rotation may be resisted by locking detents to keep the assembly 75 in the desired configuration until a force sufficient to overcome the detent is applied in the manner addressed above.
[0079] Referring to FIGS. 11A and 11B , one embodiment of the present invention focuses on a motility assembly 130 operably integrated with a partition body 10 . The assembly 130 may comprise two support arms 134 coupled for simultaneous movement. The support arms 134 may have wheels 131 to provide mobility of a partition device. The support arms 134 may have feet 132 to provide stability when a partition device is statically positioned. As represented in FIGS. 11A and 11B , a coupling of two support arms may be a gear-type interface. The support arms 134 may be attached to the partition body 10 such that the axes of rotation for the support arms are fixed relative to the partition body 10 . Rotation of either support arm 134 may cause a corresponding rotation in the other, causing the two support arms to move in-and-out in a scissor-like motion as illustrated by directional arrows 137 and 138 . Swivel wheels 131 and feet 132 may be attached at the opposite ends of the support arms 134 from the gear-type interface. The swivel wheels 131 and feet 132 may be configured to contact a support surface, but not at the same time. For example, the swivel wheels 131 and feet 132 may be configured such that when the support arms 134 are in a “V” shape, the swivel wheels 131 will be in contact with a support surface but the feet 132 will not. This provides for mobility of a partitioning device. On the other hand, the swivel wheels 131 and feet 132 may be configured such that when the support arms 134 are substantially collinear or in a flattened “V” shape, the feet 132 will be in contact with a support surface but the swivel wheels 131 will not. This provides for a partitioning device to be stably supported while statically positioned. A spring 135 may be incorporated to provide force for support arm 134 movement. Alternatively, in place of a spring, a lever accessible outside a partition body 10 may be used to apply a force for support arm movement. Additionally, a locking mechanism 136 may be incorporated to prevent unintentional movement of the support arms. The locking mechanism 136 may be released via a lever accessible outside of the partition body 10 .
[0080] Referring to FIGS. 12A-12D , an interconnect may be configured for removably attaching a plurality of partitioning devices together. An interconnect may be attached to any side or face of a partition body. An interconnect may attach to a side or face by sliding a T-bar 125 into an interlocking groove such as a T-slot, or fastening by screws, bolts, clamps, etc. A T-bar may be a part of an interconnect or a partition body. Similarly, an interlocking groove such as a T-slot may be part of an interconnect or a partition body. An interconnect may take on a variety of forms as represented by several embodiments in FIGS. 12A-12D . For example, referring to FIG. 12A , an interconnect 90 may comprise: an interconnect plate 91 , an interconnect arm 92 , and an interconnect head 93 . The plate 91 has height and width dimensions in a range from about 2 inches to about 7 inches by 1 inch to about 6 inches respectively. The plate 91 further has a depth dimension in a range from about 0.5 inch to about 1 inch.
[0081] The interconnect plate 91 is attached to the interconnect head 93 via the interconnect arm 92 . The arm 92 extends out and downward such that the head 93 or a portion of the head 93 is below a plate bottom 94 . The arm 92 is typically integrated with the plate 91 and the head 93 . Alternatively though, it can be envisioned that the arm 92 may be removably attachable to the plate 91 , the head 93 , and/or both. An interconnect may be composed of materials that allow the interconnect to function with the partition body 10 . Examples of materials include but are not limited to metals, metal blends or composites, ceramics or ceramic composites, natural materials such as wood, and the like.
[0082] Referring to FIG. 12B , one embodiment of an interconnect may comprise a ball and socket joint 140 . The ball and socket components may be removably connectable, such as by snapping together. A ball component 141 may be located on a partition device such that it may engage a socket 142 component located on another partition device. On the other hand, the ball and socket components may be permanently connected to each other and attached to partition devices once the devices are in close proximity. The ball and socket embodiment may allow an interconnect to provide 360° angle rotation of a partition device. For example, a partition device may have two ball and socket type interconnects located on opposite ends of the device at the same vertical height. Assuming no other attachment points, the partition device may be rotated about the horizontal axis created by the two interconnects. This type of interconnect may allow a broad range of motion.
[0083] Referring to FIG. 12C , another embodiment may be a cylindrical interconnect 150 . A cylindrical interconnect 150 may comprise a cylinder 151 within a cylindrical shell 152 . One type of cylindrical interconnect may resemble a door hinge. The cylindrical interconnect components may be removably connectable, such as by snapping or sliding together. A cylindrical component 151 may be located on a partition device such that it may engage a cylindrical shell component 152 located on another partition device. On the other hand, the cylindrical interconnect components may be permanently connected to each other and attached to partition devices once the devices are in close proximity. The cylindrical interconnect embodiment may allow a broad range of rotation for a partition device.
[0084] Referring to FIG. 12D , another embodiment may be a fixed angle interconnect 160 . A fixed angle interconnect may connect a plurality of partition devices without allowing a variation of the relative angle between them. Fixed angle interconnects 160 may be provided in a variety of angles. A fixed angle interconnect may resemble a “L” bracket for connecting two partition devices, a “Y” bracket for connecting three partition devices, or a “+” bracket for connecting four partition devices, etc.
[0085] Referring to FIGS. 13A-13D , the interconnects 90 are attached to the partition body 10 at multiple places. Interconnects may be attached to any face or side of the body 10 . In the case of a cuboid body 10 as represented in FIGS. 13A-13D , ten interconnects may be attached in the periphery of each rectangular face: eight in the corner regions and one on each long side. The interconnects 90 are extended a distance 95 below the bottom of the partition body 10 in a range from about 0.5 inch to about 1.5 inches. In this configuration, the body 10 is supported and stabilized in a position normal to a surface 96 that the interconnects 90 rest on.
[0086] Referring to FIGS. 14 and 15 in use of the partitioning devices, three rectangular shaped partitioning devices 5 , 6 , and 7 are provided. Each device 5 , 6 , and 7 is placed on the surface 96 with the long sides vertical. The interconnects 90 , 98 , and 102 are used to support each device 5 , 6 , and 7 , respectively, a distance 95 above the surface 96 .
[0087] Devices 5 and 6 further are placed in line with each other such that three of the interconnects 90 and three of the interconnects 98 of each device 5 and 6 are in a general vicinity of one another. The interconnects 90 and 98 may be placed a distance 110 from another. The distance 110 maybe in a range from about 0.5 inch to about 2 inches. The devices 5 and 6 may be secured to each other via a U-bolt 111 . Although a U-bolt 111 and interconnects may be described and claimed throughout the application, it should be understood that in place of U-bolt 111 and respective interconnects, many various types of connecting members may be used to join one partitioning device to another. That is, those types disclosed in FIGS. 12A , 12 B, 12 C, and 12 D are inherently included herein. Additionally included herein are those equivalents to the interconnects disclosed herein which may be known and understood by persons having skill in the art. The bolt 111 may be inserted into each interconnect head 93 and 99 so as to prevent the heads 93 and 99 , and by extension the devices 5 and 6 from separating or disengaging.
[0088] Device 7 may then be connected to the device 6 forming a generally 90° angle. Similar to the description above, device 6 and 7 may be placed near each other such that three of the interconnects 98 and three of the interconnects 102 of each device 6 and 7 are in a general vicinity of one another. The interconnects 98 and 102 may be placed a distance 110 from another. The devices 6 and 7 may be secured to each other via a U-bolt 111 . The bolt 111 may be inserted into each interconnect head 99 and 103 so as to prevent the heads 99 and 103 , and by extension the devices 6 and 7 from separating or disengaging.
[0089] The above example describes connecting the device 5 with device 6 in a generally straight line and connecting the device 6 with device 7 at a generally 90° angle via the interconnects 98 , 99 , and 102 respectively. The description is not meant to limit the scope of the configuration of the devices 5 , 6 , and 7 in use in an embodiment of the present invention. The partitioning devices 5 , 6 , and 7 as well as any other partitioning devices maybe configured in any shape allowed via the interconnects of the aforementioned devices, in accordance with the present invention.
[0090] For example, the partitioning devices may be configured in shapes such as an “L”, a “T”, a “V”, a wall, a divider, a cube, a rectangle, a triangle, and the like. The partitioning devices may also be configured so as to provide private rooms and cubicle like structures.
[0091] Referring to FIG. 16 , in use of the partitioning devices, seven rectangular shaped partitioning devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 are provided to form a private room or cubicle like structure. Each device 5 , 6 , 7 , 115 , 116 , 117 , and 118 is placed on the surface 96 with the long sides vertical. The devices respective interconnects 90 , 98 , 102 , 119 , 120 , 121 , and 122 are used to support each partitioning device a distance 95 above the surface 96 .
[0092] The devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 are placed and configured to allow formation of a cubicle like structure. The devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 are placed near each other such that the interconnects 90 , 98 , 102 , 119 , 120 , 121 , and 122 respectively of the aforementioned devices are able to be locked and secured in place relative to each other. This may be accomplished via a U-bolt 111 . The bolt 111 may be inserted into the interconnects 90 , 98 , 102 , 119 , 120 , 121 , and 122 so as to prevent the interconnects, and by extension the devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 from separating or disengaging.
[0093] The above example portrays connecting rectangular shaped partitioning devices in a configuration wherein the devices are positioned with the long sides vertical. The vertical configuration is not meant to limit the scope of the configuration of the devices in use in an embodiment of the present invention. The partitioning devices may also be configured wherein the devices are positioned with the long sides horizontal, or a combination of the two configurations in accordance with the present invention.
[0094] Referring to FIG. 17 in use of the partitioning devices, four rectangular shaped partitioning devices 5 , 6 , 7 , and 115 are provided. Devices 5 , 7 , and 115 are placed on the surface 96 with the long sides vertical and device 6 is placed with the long sides horizontal. The interconnects 90 , 98 , 102 , and 119 may be used to support each device 5 , 6 , 7 , and 115 , respectively, a distance 95 above the surface 96 .
[0095] Devices 5 , 6 , and 7 further are placed in line with each other such that two of the interconnects 90 and two of the interconnects 98 of each device 5 and 6 are in a general vicinity of one another. The devices 5 and 6 may be secured to each other via a U-bolt 111 . The bolt 111 may be inserted into each interconnect head 93 and 99 so as to prevent the heads 93 and 99 , and by extension the devices 5 and 6 from separating or disengaging. The devices 6 and 7 may also be secured to each other via a U-bolt 111 . The bolt 111 may be inserted into each interconnect 98 and 102 so as to prevent the interconnects 98 and 102 , and by extension the devices 6 and 7 from separating or disengaging.
[0096] Device 115 may be connected to the device 7 forming a generally 90° angle. Similar to the description above, device 7 and 115 are placed near each other such that three of the interconnects 102 and three of the interconnects 119 of each device 7 and 115 are in a general vicinity of one another. The devices 7 and 115 may be secured to each other via a U-bolt 111 . The bolt 111 may be inserted into each interconnect 102 and 119 so as to prevent the interconnects 102 and 119 , and by extension the devices 7 and 115 from separating or disengaging.
[0097] The above example describes connecting the partitioning devices 5 , 6 , and 7 in a generally straight line and connecting the device 115 with device 7 at a generally 90° angle via the interconnects 98 , 99 , 102 , 119 , respectively. The description is not meant to limit the scope of the configuration of the devices 5 , 6 , 7 , and 115 in use in an embodiment of the present invention. The partitioning devices 5 , 6 , 7 , and 115 as well as any other partitioning devices may be configured in any shape allowed via the interconnects of the aforementioned devices, in accordance with the present invention.
[0098] For example, the partitioning devices may be configured in shapes such as an “L”, a “T”, a “V”, a wall, a divider, a cube, a rectangle, a triangle, and the like. The partitioning devices may also be configured such that as to provide private rooms and cubicle like structures.
[0099] Referring to FIG. 18 in use of the partitioning devices, seven rectangular shaped partitioning devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 are provided to form a private room or cubicle like structure. Devices 5 , 7 , 115 , and 117 are placed on the surface 96 with the long sides vertical while devices 6 , 116 , and 118 are placed on the surface 96 with the long sides horizontal. The devices' respective interconnects 90 , 98 , 102 , 119 , 120 , 121 , and 122 may be used to support each partitioning device a distance 95 above the surface 96 .
[0100] The devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 are placed and configured to allow formation of a cubicle like structure. The devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 are placed near each other such that the interconnects 90 , 98 , 102 , 119 , 120 , 121 , and 122 , respectively, of the aforementioned devices are able to be locked and secured in place relative to each other. This may be accomplished via a U-bolt 111 . The bolt 111 may be inserted into the interconnects 90 , 98 , 102 , 119 , 120 , 121 , and 122 so as to prevent the interconnects, and by extension the devices 5 , 6 , 7 , 115 , 116 , 117 , and 118 from separating or disengaging.
[0101] The above examples each portray connecting rectangular shaped partitioning devices in a configuration wherein the rectangular shaped partitioning devices appear to be of roughly equal dimensions. The dimensions of each of the rectangular shaped partitioning devices portrayed respective to one another is not meant to limit the scope of the configuration of the devices in use in an embodiment of the present invention. That is, the rectangular shaped partitioning devices may be used to configure, for example, a table structure, a desk structure, a doored structure or a shelving structure. Further, the partitioning devices may also be configured wherein the devices are configured from a variety of dimensioned rectangular shaped partitioning devices. Therefore, configurations such as a table structure, a desk structure, a doored structure, or a shelving structure may be comprised of rectangular shaped partitioning devices with differing dimensions in accordance with the present invention.
[0102] Referring to FIG. 19 in use of the partitioning devices, eight rectangular shaped partitioning devices 5 , 6 , 7 , 201 , 202 a , 205 , 206 , 209 , 210 and 117 are provided to form a desk-like configuration. Each of the devices 5 , 205 , and 206 may be placed to contact the surface 96 such that devices 6 , 7 , 201 , 202 a , 209 and 117 do not come into contact with the surface 96 . The devices' interconnects, 90 , 98 , 102 , 219 , 220 a , 221 , 222 , 223 and 121 , may be used to support each partitioning device in, for example, a desired configuration above the surface 96 . That is, the devices 5 , 6 , 7 , 201 , 202 a , 205 , 206 , 209 , 210 and 117 are placed near each other such that the interconnects 90 , 98 , 102 , 219 , 220 a , 221 , 222 , 223 and 121 , respectively, of the aforementioned devices may be locked and secured in place relative to each other. This may be accomplished via a U-bolt 111 . The U-bolt 111 may be inserted into interconnects 90 , 98 , 102 , 219 , 220 , 221 , 222 , 223 and 121 so as to prevent interconnects and by extension, the devices 5 , 6 , 7 , 201 , 202 a , 205 , 206 , 209 and 117 , from separating or disengaging. That is, in FIG. 19 , a U-bolt 111 may be placed into two interconnects (for example, 220 a and 223 ) of two different rectangular-shaped partitioning devices ( 202 a and 209 , respectively) so as to hold the two rectangular shaped partitioning devices together. This may be repeated for each side of a rectangular-shaped partitioning device that may, for example, be in close proximity to a side of another rectangular-shaped partitioning device so that the two may be secured together.
[0103] As shown in FIG. 19 , once a desk-like structure is configured, the rectangular-shaped partitioning device 202 a that is securedly suspended over surface 96 may be moved in such a manner so that the device may come to a rest at a point depicted by phantom rectangular-partitioning device 202 b . Rectangular-shaped partitioning device 202 a may be initially secured to mini-panels 209 and 210 via U-bolts 111 (or other type of interconnector, as previously discussed) connecting interconnects 220 a , 223 , and 224 , of panels 202 a , 209 , and 210 , respectively, to create a desk-like configuration. Thereafter, the U-bolts 111 may be removed from interconnects 220 a , 223 , and 224 , and moved by various means. Further, examples that are set forth in the following paragraphs are meant to be illustrative, and non-limiting to the manner in which the panel device 202 a may be moved into the phantom panel device 202 b placement.
[0104] As a first example, the rectangular-shaped partitioning device 202 a may, for example, be removably attached from either of the (now free-standing) configurations located proximal to the initial placement of rectangular-shaped partitioning panel 202 a . The phantom rectangular-shaped partitioning panel 202 b may then be removably reattached to the minipanels 209 and 210 , but on different sides of the respective minipanels than those that were previously the sites of interconnection. U-bolts 111 may then be used to secure the interconnects 220 b (of 202 b ) to the interconnects 223 and 224 of minipanels 209 and 210 , respectively. In such a fashion, the rectangular-shaped partitioning device 202 b (depicted as a phantom in FIG. 19 ) may then be substantially perpendicular to the surface 96 .
[0105] As a second example, the rectangular-shaped partitioning device 202 a may be equipped with a rotating member 240 that is removably attached to minipanels 209 and 210 respectively. The rectangular-shaped partitioning device 202 a may either be coupled to or integral to the rotating member 240 . Also, the rotation of panel 202 a may be done in various intervals or portions. Using this manner, when the U-bolts 111 are removed from the various interconnects 220 a , 223 , and 224 , the panel device 202 a may be rotatably moved along the axis of rotating member 240 to create any degree of inclination of phantom rectangular-shaped partitioning device 202 b from the initial state of panel device 202 a . That is, the panel device 202 a may be freely rotated with the rotating member 240 about an axis in a 360 degree fashion, and the phantom panel 202 b of FIG. 19 represents but one resting place of the device after rotation may be completed. Further, the phantom panel may be secured into place with U-bolts 111 and interconnects 220 b , 223 , and 224 . Alternatively, the phantom panel may be secured into place by a rotation preventing member 241 of the rotating member 240 . Such a rotation preventing member may comprise any such means known and used by those skilled in the art. A rotation preventing member 241 may, for example, be either a brake member. That is, the brake member may act upon the points into which the rotating member 240 is removeably attached to the rectangular-shaped mini panels 209 and 210 .
[0106] Referring again to FIG. 19 , the interconnects 121 of device 117 may be secured to devices 205 and 206 at each of their respective interconnects, 221 and 222 , in such a manner that device 117 may create a shelf-like structure in cooperation with devices 205 and 206 . That is, the interconnects of each panel may be located in a plurality of locations such that one, two, or more shelves may be built from into configuration of the interlocking partitioning devices. Further, the shelf-like or tabletop-like configurations of panel devices 6 , 202 a , and 117 may be constructed to be load bearing for certain materials or amounts. For example, if the load were known to be great, cause an unequal weight distribution, there may be different materials used in the rectangular-shaped partitioning device that would hold all of the loaded materials on its surface area. Alternatively, if the load were known to cause an unequal weight distribution, the u-bolts may be composed of materials with a greater tensile strength, constructed with a greater diameter, or constructed with a superior weight bearing geometric shape (for example, a hexagonal configuration) than other U-bolts 111 of the configuration. Additionally, although not depicted in FIG. 19 , any of the interconnect configurations known and appreciated in the art, as well as those previously illustrated, for example, in FIGS. 12A , 12 B, 12 C, 12 D, and 15 may be used in various configurations.
[0107] The above examples each portray rectangular shaped partitioning devices in a configuration wherein the rectangular shaped partitioning devices appear without any inconsistencies in the face of the device. The homogenously appearing face of the rectangular shaped partitioning devices is not meant to limit the scope of the configuration of the devices in use in an embodiment of the present invention. That is, the rectangular shaped partitioning devices may be configured to have one or more openings in the face of the rectangular partitioning device. Also, the openings may be made of the same material as the rectangular shaped partitioning device, or it may be comprised of different materials.
[0108] Referring to the rectangular-shaped partitioning device 201 of FIG. 19 , a partitioning device may be configured to have openings in its face. The openings in device 201 , for example, may have removably attached covers or doors to cover the opening. As illustrated, device 201 has two openings in its face. However, a device may have no openings, one opening, or a plurality of openings in its face. Further, an opening in a partitioning device may transgress through the entirety of a face of a partitioning device. Alternatively, the opening may only go through a portion of the rectangular-shaped partitioning device. Such examples will be discussed further, infra. As shown in FIG. 19 , a removably attached door 203 a may have interconnects 204 , and may be connected to the interconnects 219 of the rectangular shaped partitioning device 201 by u-bolts 111 . However, it should be noted that although interconnects shown in FIG. 15 are depicted, any of the interconnects illustrated in FIGS. 12A , 12 B, 12 C, or 12 D, or any other interconnects known and appreciated in the art may be used. As shown in FIG. 19 , one side of the removably attached door 203 a may be connected to the rectangular shaped partitioning device 201 with the interconnects. When interconnected in this fashion, the removably attached door 203 a may be swung along the axis of movement created by the interconnects and U-bolts 111 , and with such movement, the removably attached door 203 a may be opened and closed. The open configuration is illustrated by the phantom door 203 b . The closed configuration will be more thoroughly discussed below.
[0109] For example, the removably attached door 203 a may fit into the opening of rectangular partitioning device 201 so as to create a consistent surface area. Alternatively, the door removably attached 203 a may fit onto or over the opening in rectangular shaped partitioning device 201 such that at least a portion of the removably attached door 203 a may create an inconsistency in the surface of the rectangular shaped partitioning device 201 that may be readily visible by an observer. Also, if the door is in either configuration, the removably attached door 203 a may be secured in a closed position so that it may not freely open. For example, an additional interconnect may be present on the removably attached door 203 a and the rectangular shaped partitioning device 201 such that at least one additional side of the removably attached door 203 a may be interconnected to the device 201 with interconnects 204 . Alternatively, there are many attaching means available in the art to secure the removably attached door 203 a to the rectangular shaped partitioning device 201 . For example, the door 203 a may be removably secured to the rectangular shaped partitioning device 201 with a hook and loop, button and hole, zipper, Velcro® hook and eye, button and snap, a door knob and accompanying bar, et cetera. Alternatively, the removably attached door 203 a may not be connected with interconnects; rather, the removably attached door may be configured to fit inside of the rectangular shaped partitioning device 201 and translationally slide open to reveal the opening or slide closed to close the opening.
[0110] Although FIG. 19 shows that removably attached door 203 a may be removably attached to the rectangular partitioning device, the removable cover 207 a may be completely removed from the rectangular shaped partitioning device 201 to yield an opening. This completely removed position of the removable cover 207 a is depicted in FIG. 19 by the phantom removable cover 207 b . Similar to door 203 a , the removable cover 207 a may be either (a) fitted into the opening of device 201 so that there are no visual surface irregularities in the face of device 201 or (b) fitted over or onto the rectangular shaped partitioning device 201 so that at least a portion of the removable cover 207 a is readily visible to an observer. Similarly, the removable cover 207 a , while in a closed position, may be secured as previously discussed with respect to removably attached door 203 a . Also, the removable cover 207 a may be, for example, a portion of the rectangular shaped partitioning device. For example, as depicted in FIG. 19 , the device 201 may have had a preexisting substantial perforation along a predetermined perimeter. At the user's option, then, the perforation into the rectangular shaped partitioning device may be completed, and the removable cover 207 a may be removed. Alternatively, the removable cover 207 a may have been placed either on or in the rectangular shaped partitioning device 201 in such a manner that it was already completed detached from the device 201 and ready to be removed from the apparatus by a user.
[0111] With respect to any doors or covers associated with covering an opening in a rectangular shaped partitioning device, the doors or covers may be labeled or otherwise denoted (e.g. different colored or patterned material from the remainder of the partitioning device) so that they may indicate to a user that a door or cover exists in the partitioning device that may be removably attached or completely removed therefrom. Specifically referring to FIG. 19 , upon removal of either the removably attached door 203 a or the completely removable cover 207 a , the opening in the partitioning device 201 may be either a complete via from one side of the rectangular shaped partitioning device to the other, or an inner pane 208 .
[0112] The inner pane 208 may be designed to facilitate the transfer of either light or sound, or a combination thereof. That is, inner pane 208 may, for example, be composed of a transparent or translucent material that would allow light to propagate from one side of device 201 through inner pane 208 to the other side of device 201 . [It should be mentioned that there are also some opaque materials that may still transfer light therethrough, given an appropriate thickness or density of the opaque material. Such materials, given the properties aforementioned, are also inherently included in the current discussion.] For example, the inner pane 208 may be completely transparent to facilitate an observer's or user's vision through device 201 , in effect creating a window in the rectangular partitioning device 201 with either a cover 207 a or a removably attached door 203 a . As another example, the inner pane 208 may be translucent to facilitate the filtration of light from one side of the device 201 to the other side of device 201 , while fostering privacy of the environment of one side of the device 201 from the other side of the device 201 by maintaining a limited visibility through the pane 208 . Additionally, as previously stated, the device 201 may comprise an inner pane 208 that facilitates the propagation of sound from one side of the device 201 to the other side of device 201 . That is, the inner pane 208 may be comprised of a material less dense than the device 201 , a material with a small thickness, or of a material with a plurality of vias or perforations therethrough, such that sounds may easily transfer from one side of the device 201 to the other side of device 201 . An inner pane 208 for light or sound propagation may be useful in cases where a configuration of rectangular shaped partitioning devices comprises several devices which are of a substantial surface area, or where a configuration comprises many individual devices. In such exemplary cases, it would benefit a user to be able to listen, see or otherwise communicate through an inner pane 208 . Finally, the pane may comprise a combination of both sound and light propagating materials. Such an arrangement may allow a user to see, listen, communicate, and observe an environment from one side of the device 201 to the other side of device 201 . Additionally, the environment on one side of the device 201 may benefit from the filtration of light from one side of the device 201 to the other side of device 201 .
[0113] In addition to light and sound propagation, the inner pane 208 may also be composed of a material that is either heat conductive or heat resistant. With such a material comprising the inner pane 208 , temperature regulation or fluctuation may be facilitated and more easily and efficiently accomplished. This may be beneficial, for example, when regulating an ambient temperature of one or more configurations that do not individually have access to one or more temperature regulating means.
[0114] Modifications and variations of the described apparatus and methods of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific embodiments, outlined above, it should be understood that the invention should not be unduly limited to such specific embodiments. Various changes may be made without departing from the spirit and scope of the invention as defined in the following claims. | The invention relates generally to partitioning devices and methods for partitioning space. A device is presented comprising: at least one partition body; at least one motility assembly operably adapted to at least one partition body; and at least one interconnect, where the at least one interconnect is used to interchangeably link the at least one partition body in multiple configurations with another partition body. A method for partitioning space is presented comprising: providing a first partitioning device, where the partitioning device includes at least one interconnect, where the interconnect is used to interchangeably link the partitioning device body with a second partitioning device body; providing at least a first removably attachable portion on the first partitioning device; removing the removably attachable portion; and replacing the removably attachable portion with a second removably attachable portion, where the removably attachable portion is different than the first removably attachable portion. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a phosphorus acid functionalized opaque polymer, which is useful as an additive in pigmented coating formulations.
[0002] Opaque polymers are well known as additives in pigmented coating formulations such as paints and are used to improve hiding of coated substrates. Opaque polymers are used to reduce the load of the comparatively expensive TiO 2 in formulations without sacrificing hiding, or to maintain the same levels of TiO 2 to improve hiding. Opaque polymers can be prepared, for example, as described in U.S. Pat. No. 6,020,435.
[0003] It would be an advance in the field of pigmented coating compositions to discover an additive with improved hiding capability.
SUMMARY OF INVENTION
[0004] The present invention addresses a need in the art by providing a method for preparing an aqueous dispersion of phosphorus acid functionalized core-shell polymer particles comprising the steps of a) contacting under emulsion polymerization conditions i) a first monomer emulsion with ii) an aqueous dispersion of carboxylic acid functionalized polymer particles having an average particle size of from 80 to 180 nm to form an aqueous dispersion of core-shell polymer particles; then b) plasticizing the shell portion of the core-shell polymer particles with a polymerizable plasticizing agent; then c) contacting the core-shell polymer particles with an aqueous base to swell the core without substantially polymerizing the plasticizing agent; then d) polymerizing the plasticizing agent;
[0005] wherein the first monomer emulsion comprises a) from 0.1 to 5 weight percent of a phosphorus acid monomer, based on the weight of the monomers in the first monomer emulsion; and b) from 50 to 99.8 weight percent of a first nonionic ethylenically unsaturated monomer which, when polymerized, has a T g of at least 50° C. and a refractive index of at least 1.4; and c) from 0.1 to 15 weight percent of a carboxylic acid functionalized monomer;
[0006] wherein the acid functionalized polymer particles comprise from 20 to 50 weight percent structural units of a carboxylic acid monomer, based on the weight of the polymer particles; and 50 to 80 weight percent of structural units of a second nonionic ethylenically unsaturated monomer;
[0007] wherein the plasticizing agent comprises from 7 to 30 percent of a third nonionic ethylenically unsaturated monomer based on the weight of the polymer particles;
[0008] wherein the phosphorus acid functionalized core-shell polymer particles have an average particle size in the range of 250 nm to 1.6 μm.
[0009] The phosphorus acid functionalized core-shell polymer particles are useful in forming composite with TiO 2 particles, which composites improve hiding efficiency in paint formulations.
DETAILED DESCRIPTION OF THE INVENTION
[0010] In a first aspect, the present invention is a method for preparing an aqueous dispersion of phosphorus acid functionalized core-shell polymer particles comprising the steps of a) contacting under emulsion polymerization conditions i) a first monomer emulsion with ii) an aqueous dispersion of carboxylic acid functionalized polymer particles having an average particle size of from 80 to 180 nm to form an aqueous dispersion of core-shell polymer particles; then b) plasticizing the shell portion of the core-shell polymer particles with a polymerizable plasticizing agent; then c) contacting the core-shell polymer particles with an aqueous base to swell the core without substantially polymerizing the plasticizing agent; then d) polymerizing the plasticizing agent;
[0011] wherein the first monomer emulsion comprises a) from 0.1 to 5 weight percent of a phosphorus acid monomer, based on the weight of the monomers in the first monomer emulsion; and b) from 50 to 99.8 weight percent of a first nonionic ethylenically unsaturated monomer which, when polymerized, has a T g of at least 50° C. and a refractive index of at least 1.4; and c) from 0.1 to 15 weight percent of a carboxylic acid functionalized monomer;
[0012] wherein the acid functionalized polymer particles comprise from 20 to 50 weight percent structural units of a carboxylic acid monomer, based on the weight of the polymer particles; and 50 to 80 weight percent of structural units of a second nonionic ethylenically unsaturated monomer;
[0013] wherein the plasticizing agent comprises from 7 to 30 percent of a third nonionic ethylenically unsaturated monomer based on the weight of the polymer particles;
[0014] wherein the phosphorus acid functionalized core-shell polymer particles have an average particle size in the range of 250 nm to 1.6 μm.
[0015] The first monomer emulsion comprises from 0.1, preferably from 0.2, more preferably from 0.5 weight percent, to 5, more preferably to 3, and most preferably to 2 weight percent of a phosphorus acid monomer, based on the weight of monomers in the first monomer emulsion. The first monomer emulsion further comprises, based on the weight of monomers in the first monomer emulsion, from 50, more preferably from 70, and most preferably from 85 weight percent, to 99.8, and more preferably to 95 weight percent of a first nonionic ethylenically unsaturated monomer which, when polymerized, has a T g of greater than 50° C. as calculated by the Fox equation and a refractive index (R f ) of at least than 1.4.
[0016] Examples of suitable phosphorus acid monomers include phosphonates and dihydrogen phosphate esters of an alcohol in which the alcohol contains or is substituted with a polymerizable vinyl or olefinic group. Preferred dihydrogen phosphate esters are phosphates of hydroxyalkyl methacrylates, including phosphoethyl methacrylate and phosphopropyl methacrylates, with phosphoethyl methacrylate being especially preferred. “Phosphoethyl methacrylate” (PEM) is used herein to refer to the following structure:
[0000]
[0017] where R is H or
[0000]
[0018] wherein the dotted line represents the point of attachment to the oxygen atom.
[0019] Examples of suitable first nonionic ethylenically unsaturated monomers include styrene, methyl methacrylate, acrylonitrile, and t-butyl acrylate, as well as combinations thereof. Styrene or a combination of styrene and acrylonitrile are preferred monomers. When styrene and acrylonitrile are both used, the preferred w/w ratio of styrene to acrylonitrile is from 98:2 to 85:15.
[0020] The first monomer emulsion further comprises from 0.1, preferably from 0.2, and more preferably from 0.5 weight percent, to 15, more preferably to 10, and most preferably to 5 weight percent of a carboxylic acid functionalized monomer, based on the weight of the monomers in the first monomer emulsion. Examples of suitable carboxylic acid functionalized monomers include acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid, with acrylic acid or methacrylic acid being preferred.
[0021] The first monomer emulsion may include other monomers. For example, the first monomer emulsion may include a polyethylenically unsaturated monomer at a concentration from 0.1, more preferably from 0.2, to preferably 20, more preferably to 10, more preferably to 5, and most preferably to 2 weight percent, based on the weight of monomers in the first monomer emulsion. Preferred polyethylenically unsaturated monomers are diethylenically unsaturated monomers and triethylenically unsaturated monomers such as allyl methacrylate (ALMA), divinyl benzene (DVB), ethylene glycol diacrylate (EGDA), ethylene glycol dimethacrylate (EGDMA), trimethylolpropane triacrylate (TMPTA), and trimethylolpropane trimethacrylate (TMPTMA).
[0022] The carboxylic acid functionalized polymer particles comprise a) preferably from 25, and more preferably from 32 weight percent, to 50, preferably to 40, and more preferably to 36 weight percent structural units of a carboxylic acid monomer, preferably acrylic acid or methacrylic acid, based on the weight of the polymer particles; and b) preferably from 60, and more preferably from 64 weight percent, to preferably to 75, and more preferably to 68 weight percent structural units of a second nonionic ethylenically unsaturated monomer, based on the weight of the acid functionalized polymer particles. Examples of preferred second nonionic ethylenically unsaturated monomers include methyl methacrylate and styrene, with methyl methacrylate being more preferred. The acid functionalized polymer particles preferably have an average diameter of from 100 nm, more preferably from 125 nm to preferably 160 nm, more preferably to 150 nm, and most preferably to 140 nm, as determined by a BI90 Plus Particle Size Analyzer.
[0023] The first monomer emulsion and the aqueous dispersion of acid functionalized polymer particles are contacted together under emulsion polymerization conditions to form an aqueous dispersion of core-shell polymer particles. Preferably, the phosphorus acid monomer portion of the first monomer emulsion is added to a vessel containing the aqueous dispersion of polymer particles in a staged fashion such that all of the phosphorus added monomer is added to the reaction vessel over a shorter period of time than the other monomers of the monomer emulsion. More preferably, the phosphorus acid monomer is added over a period that is less than 60%, of the total monomer emulsion time of addition. Most preferably, the phosphorus acid monomer addition is delayed until 40% to 75% of the monomer emulsion, absent the phosphorus acid monomer, is added to the reaction vessel. It has been surprisingly discovered that staging of the addition of the phosphorus acid monomer has a marked effect on the extent of composite formation, which, in turn advantageously impacts the hiding observed in the final coated product.
[0024] The polymerization is allowed to proceed to a desired degree of conversion of monomer in the first monomer emulsion, preferably at least 90%, more preferably at least 95%, and most preferably at least 98% conversion of monomers; once the desired degree of conversion is achieved, the reaction is preferably inhibited to stop or substantially stop the polymerization of unreacted residual monomer. Inhibition is preferably carried out using an inhibitor or a redox pair. Examples of suitable inhibitors include 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl, (4-hydroxy-TEMPO), 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO), monomethyl ether hydroquinone (MEHQ), and 4-t-butyl catechol. Examples of suitable redox pairs include combinations of an oxidant such as t-butyl hydroperoxide (t-BHP); t-amyl hydroperoxide (t-AHP), sodium persulfate (NaPS), ammonium persulfate (APS), and hydrogen peroxide, with a reductant such as isoascorbic acid (IAA), sodium bisulfite, and sodium sulfate. It is also possible, though not necessarily preferable, to stop or substantially stop polymerization by allowing the reaction to run to completion or substantial completion.
[0025] A polymerizable plasticizing agent is then contacted with the phosphorus acid functionalized core-shell polymer particles to plasticize the shell, thereby providing a means for the subsequently added aqueous base to penetrate the shell (with concomitant swelling of the polymer particles) and fill the core with water neutralized to a pH of at least 6, more preferably at least 7, to 10 more preferably to 9. Examples of suitable bases include alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal carbonates, alkaline earth metal carbonates, amines, and NH 4 OH, with NaOH, KOH, and NH 4 OH being particularly preferred bases.
[0026] The polymerizable plasticizing agent can be any ethylenically unsaturated monomer but is preferably either a monomer having a T g of greater than 50° C. (that is, the homopolymer of the monomer has a T g of greater than 50° C. as calculated by the Fox equation) or a low T g monomer copolymerized with a crosslinking agent. Examples of preferred polymerizable plasticizing agents include styrene or methyl methacrylate, or a combination of butyl acrylate and divinyl benzene or allyl methacrylate.
[0027] The polymerizable plasticizing agent is used at a concentration of preferably from 10, and more preferably from 12 weight percent, to preferably to 25, and more preferably to 20 weight percent, based on the weight of the core-shell polymer particles. It is understood that the polymerizable plasticizing agent may include unreacted monomer from the first monomer emulsion; although not preferred, it is possible that the polymerizable plasticizing agent arises entirely from unreacted monomer. It is preferred however, that additional polymerizable plasticizing agent be contacted with the aqueous dispersion of core-shell polymer particles.
[0028] Once the polymer particles have swollen to their desired levels, the polymerizable plasticizing agent is then polymerized. It is preferred that less than 1%, more preferably less than 0.1%, and most preferably less than 0.01% of residual polymerizable plasticizing agent remains after this polymerization step.
[0029] The phosphorus acid functionalized polymer particles are advantageously admixed with pigment particles such as an aqueous slurry of TiO 2 particles—especially TiO 2 particles surface-treated with silane or alumina—to form composites that are useful in providing opacity in coating compositions such as paint formulations, paper coatings, ink jet coatings, printing inks, sunscreens, nail polish, and wood coatings.
[0030] The formulation may also include any of a variety of other materials such as fillers; binders; rheology modifiers; dispersants, surfactants; defoamers; preservatives; flow agents; leveling agents; and neutralizing agents. It has been discovered that the composites confer additional hiding benefits for the formulation as compared with non-composite forming aqueous blends of opaque polymer and pigment particles.
[0031] In a second aspect, the present invention is a composite comprising an aqueous dispersion of phosphorus acid functionalized core-shell polymer particles adsorbed to TiO 2 particles, wherein the core comprises water having a pH of at least 6 and not more than 10; wherein the average diameter of the core is from 200 nm to 1.4 μm, and the average diameter of the core-shell particles is from 225 nm to 1.6 μm; wherein the shell comprises a) from 50 to 99.8% of a polymer or a copolymer having a T g of not less than 50° C. and a refractive index of from 1.4 to 2; and b) from 0.1 to 5 weight percent structural units of a phosphorus acid monomer.
[0032] The phosphorus acid functionalized core-shell polymer particles have a preferred final core diameter in the range of from 250 nm, and more preferably from 275 nm, to preferably 500 nm, more preferably to 400 nm, and most preferably to 350 nm, as determined by the void fraction measurement described in the Examples Section. The diameter of the final core-shell polymer particles is preferably in the range of from 250 nm, more preferably from 275 nm, and most preferably from 300 nm, to preferably 550 nm, more preferably to 425 nm, and most preferably to 375 nm, as determined using a BI90 Plus Particle Size Analyzer. The void fraction of the final core-shell polymer particles (that is, the volume of the final core to the total volume of the final core-shell polymer particles) is preferably in the range of from 30%, more preferably from 35%, and most preferably from 40%, to preferably 70%, more preferably to 60%, and most preferably to 46%.
EXAMPLES
Abbreviations
[0033]
[0000]
NaPS
Sodium Persulfate
MMA
Methyl Methacrylate
MAA
Methacrylic Acid
AA
Acrylic Acid
SDS
Sodium Dodecylsulfate (23% aq)
STY
Styrene
AN
Acrylonitrile
EDTA
Ethylenediaminetetraacetic Acid Tetrasodium salt
IAA
Isoascorbic Acid
BA
Butyl Acrylate
DVB
Divinyl Benzene
4-hydroxy TEMPO
4-Hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl
t-BHP
t-Butylhydroperoxide
PEM
Phosphoethyl Methacrylate (60% active)
ALMA
Allyl Methacrylate
PS
Particle Size
Comparative Example 1
Preparation of an Opaque Polymer without Phosphorus Acid Functionality
[0034] To a 5-liter, four necked round bottom flask was equipped with paddle stirrer, thermometer, nitrogen inlet, and reflux condenser was added DI water (700 g) under N 2 . The contents were heated 89° C., whereupon NaPS (3.40 g) dissolved in DI water (40 g) was added followed immediately by the addition of 66 MMA/34 MAA seed material prepared substantially as described in U.S. Pat. No. 6,020,435, Examples 1-16 (200.00 g, 32% solids, PS=140 nm, by BI90 Plus Particle Size Analyzer).
[0035] A first monomer emulsion (ME I), which was prepared by mixing DI water (320 g), SDS (15.9 g), STY (803.0 g), AN (90.2 g), and linseed oil fatty acid (3.5 g) was added to the kettle at a rate of 6.0 g/min at a temperature of 78° C. Two minutes after the start of the ME I addition, a solution of AA (9.0 g) mixed with DI water (50 g) was added to the kettle. After 30 min from the start of the ME I addition, the feed rate was increased to 12 g/min, and a mixture of sodium persulfate (0.85 g) dissolved in DI water (40 g) was co-fed to the kettle at a rate of 1.0 g/min. The temperature of the reaction mixture was then allowed to increase to 84° C. After 45 min from the start of the ME I addition, the feed rate was increased to 24 g/min and the temperature was allowed to increase to 92° C. After 60 min from the start of the ME I addition, the feed rate was increased to 30 g/min. Upon completion of the ME I and co-feed additions, a solution of ferrous sulfate (0.02 g) dissolved in DI water (20 g) was mixed with a solution of EDTA (0.02 g) dissolved in two g of DI water. This mixture was added to the kettle along with a separate solution of IAA (0.71 g) dissolved in DI water (20 g). The batch was then held at 90° C. for 15 min; a second monomer emulsion (ME II), which was prepared by mixing DI water (40 g), SDS (3.4 g), BA (107.0 g), DVB (37.72 g) and 4-hydroxy TEMPO (2.5 g) was added to the kettle at a rate of 45 g/min along with hot DI water (900 g). A solution of ammonium hydroxide (40.0 g, 28% aq) in DI water (40 g) of was then added to the kettle over 5 min. The batch was then held for five min at 85° C., after which time a solution t-BHP (1.5 g) mixed with DI water (40 g) and a solution of IAA (0.85 g) mixed with DI water (40 g) was co-feed to the kettle at a rate of 0.8 g/min. After completion of the t-BHP and IAA co-feed, the batch was cooled to room temperature and filtered to remove any coagulum formed. The final latex had a solids content of 30.5%.
Examples 1-5
Preparation of Phosphoethyl Methacrylate Functionalized Opaque Polymer
[0036] The Examples were prepared by the procedure of Comparative Example 1 except that for Examples 1-3, PEM was added to the ME1tank after 75% of ME1 was added to the kettle; for Examples 4-5, PEM was added to the ME1tank after 33% of ME1 was added to the kettle.
[0037] Void Fraction Determination
[0038] Void fraction of the opaque polymers was determined using three separate bulking cup weight measurements. For the first measurement, a triethylene glycol (TEG)-water blank is prepared by placing TEG (90.00 g) and water (10.00 g) in a 4-oz jar. The TEG and water were stirred to form a thoroughly dispersed mixture, which was poured into a tared bulking cup. The weight of this mixture (the blank, designated BL for ensuing calculations) was obtained. The second measurement was obtained by pouring the opaque polymer emulsion into a tared bulking cup and obtaining the weight of the opaque polymer emulsion (designated OP for ensuing calculations). For the third measurement, a mixture of TEG and opaque polymer emulsion was prepared by placing TEG (90.00 g) with stirring into a 4-oz jar. Opaque polymer emulsion was added to the jar that was calculated to be equal to the amount of emulsion that contains 10.00 g of water. Within 2 min of adding the aliquot of opaque polymer emulsion to the TEG, the mixture was poured into a tared bulking cup and the weight (the weight of the OP/TEG mixture, designated “OP-A” for ensuing calculations) was obtained.
[0039] Void fractions of the opaque polymers were in accordance with the below equations. In addition to the values obtained through the bulking cup measurements, the solids content of the opaque polymer emulsion also must be known (“Solids”). The result of the calculations is the void fraction (% VF) of the opaque polymer.
[0040] Equation Nomenclature
[0000]
BL
Weight of the TEG/water blank (in grams)
OP
Weight of the opaque polymer emulsion (in grams)
OP a
Weight of the opaque polymer emulsion/TEG mixture (in grams)
Solids
Percent of the opaque polymer emulsion that remains solid when
dried, expressed as a decimal between 0 and 1
WBV
Wet bulking value of the opaque polymer emulsion
DBV
Dry bulking value of the opaque polymer
SBV
Bulking value of the solid opaque polymer
TEGS
Intermediate calculation value associated with the TEG and
solids content
PS
Particle Size
% VF
Void fraction of the opaque polymer, express as a percentage
[0041] Calculation of the Void Fraction
[0000]
%
VF
=
1
-
SBV
DBV
wherein
,
SBV
=
(
1
-
(
1
-
Solids
)
×
0.1202
WBV
)
×
WBV
Solids
DBV
=
10
TEGS
×
(
1
OPa
-
(
1
-
TEGS
)
BL
)
WBV
=
10
OP
OPa
=
10
1
-
Solids
TEGS
=
OP
×
Solids
OPa
+
90
[0042] Determination of the Opaque Polymer Void Diameter
[0043] The void diameter of the opaque polymer can be calculated using the particle size of the opaque polymer particle and the void fraction of the opaque polymer particle. The void diameter was calculated as follows:
[0000] Void Diameter=(% VF×(PS/2) 3 ) 1/3
[0044] Table 1 Stage ratio refers to the ratio of the Core to the Inner Shell (ME I) to the Outer Shell (ME II).
[0000]
TABLE 1
Compositions of Opaque Polymers
Ex. No.
1
2
3
4
5
Comp. 1
PEM % a
0.5
1.0
1.5
1.5
1.5
0
Stage ratio
1:14:2.14
1:14:2.14
1:14:2.14
1:14:2.14
1:14:2.14
1:14:2.14
Core MMA:MAA
66:34
66:34
66:34
66:34
66:34
66:34
Core PS (nm)
140
140
140
83
108
140
ME I
STY
88.42
87.85
87.3
91.45
91.45
89
AN
10
10
10
5
5
10
AA
1.0
1.73
1.0
0
0
1.0
MAA
0
0
0
1.5
1.5
0
PEM a
0.58
1.15
1.73
1.8
1.8
0
ALMA
0
0
0
0.25
0.25
0
MEII
BA
78
78
78
0
0
78
STY
0
0
0
100
100
0
DVB
22
22
22
0
0
22
Particle Size
458
375
360
270
330
423
Void Fraction
40.0
37.9
37.2
38.1
42
39.4
a unadjusted for PEM activity (60% of reported amount).
[0045] The opaque polymers were formulated into paints in accordance with Table 2. (ACRYSOL and RHOPLEX are Trademarks of The Dow Chemical Company or its Affiliates.)
[0000]
TABLE 2
Paints Formulated with Opaque Polymers
Material Name
Kg
L
Premix
OP
30.56
2.08
Ammonia (28% aq.)
0.48
0.04
Water
23.56
1.64
Foamstar A-34 Defoamer
0.48
0.03
Kronos 4311 TiO 2
136.38
4.07
Premix Sub-total
191.46
7.87
LetDown
RHOPLEX ™ VSR-1050 Binder
214.09
14.25
Texanol Coalescent
6.04
0.44
ACRYSOL ™ RM-2020 NPR Rheology Modifier
6.96
0.46
ACRYSOL ™ RM-8W Rheology Modifier
2.25
0.15
Water
46.45
3.24
Total
467.25
26.42
[0046] Kubelka-Munk S/mil Test Method
[0047] Four draw-downs were prepared on Black Release Charts (Leneta Form RC-BC) for each paint using a 1.5-mil Bird draw down bar and the charts allowed to dry overnight. Using a template, 3.25″×4″ rectangles were cut out on each chart. The Y-reflectance was measured using a X-Rite Color i7 Spectrophotometer in each of the scribed areas five times and the average Y-reflectance recorded. A thick film draw down was prepared for each paint on the Black Release Charts using a 3″, 25-mil block draw down bar and the charts were allowed to dry overnight. The Y-reflectance was measured in five different areas of the draw down and the average Y-reflectance recorded. Kubelka-Munk hiding value S is given by Equation 1:
[0000]
S
=
R
X
×
(
1
-
R
2
)
×
ln
[
1
-
(
R
B
×
R
)
1
-
R
B
R
]
Equation
1
[0000] where X is the average film thickness, R is the average reflectance of the thick film and R B is the average reflectance over black of the thin film. X can be calculated from the weight of the paint film (W pf ), the density (D) of the dry film; and the film area (A). Film area for a 3.25″×4″ template was 13 in 2 .
[0000]
X
(
mils
)
=
W
pf
(
g
)
×
1000
(
mil
/
in
)
D
(
lbs
/
gal
)
×
1.964
(
g
/
in
3
/
lbs
/
gal
)
×
A
(
in
)
[0048] The Hiding (S/mil) data for Paint Examples and Comparative Example are summarized in Table 3.
[0000]
TABLE 3
Dry Hiding for Paint Samples
Ex. 1
Ex. 2
Ex. 3
Ex. 4
Ex. 5
Comp. Ex. 1
PEM % a
0.5%
1%
1.5%
1.5%
1.5%
0%
Dry S/mil
6.29
6.42
6.65
6.52
6.50
6.15
Stdev
0.03
0.05
0.03
0.06
0.07
0.00
a unadjusted for PEM activity (60% active)
[0049] The data show that the PEM-functionalized samples all exhibit higher dry hiding than the sample containing the non-PEM functionalized opaque polymer. Evidence of composite formation between the PEM-functionalized opaque polymer and the TiO 2 was found using Asymmetric Flow Field Flow Fractionation fractograms, which showed an increase in particle size as compared with the unfunctionalized opaque polymer. The mixture of VSR 1050 binder, the non-PEM-functionalized opaque polymer, and the TiO 2 particles showed a bimodal distribution of particles at 120 nm (the binder) and about 400 nm (an unbound mixture of the opaque polymer and TiO 2 ); the mixture containing the binder, the PEM-functionalized opaque polymer, and the TiO 2 gave a trimodal distribution of particles at 120 nm, 300 nm (unbound TiO 2 ), and a peak at about 700 nm, which shows evidence of opaque polymer-TiO 2 composite formation. | The present invention relates to opaque polymers functionalized with phosphorus acid groups, composites of TiO 2 particles and the opaque polymers, and methods for their preparation. The composites are useful in coatings formulations and have been shown to exhibit improved hiding benefits in coated substrates over compositions containing non-functionalized opaque polymer and TiO 2 . | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. patent application Ser. No. 10/914,640, filed on Aug. 9, 2004, now U.S. Pat. No. 7,247,238 which is a continuation application, under 35 U.S.C. §120, of International Patent Application No. PCT/AU03/00179, filed on Feb. 12, 2003 under the Patent Cooperation Treaty (PCT), which was published by the International Bureau in English on Aug. 21, 2003, which designates the United States, and which claims the benefit of Australian Provisional Patent Application No. PS 0466, filed Feb. 12, 2002, each of which is incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to HALAR® (ethylene chlorotrifluoroethylene copolymer, or poly(ethylene chlorotrifluoroethylene)) and related membranes for use in ultrafiltration and microfiltration and in particular to membranes in the form of hollow fibres, and to methods of preparing said membranes.
BACKGROUND OF THE INVENTION
The following discussion is not to be construed as an admission with regard to the common general knowledge in Australia.
Synthetic polymeric membranes are well known in the field of ultrafiltration and microfiltration for a variety of applications including desalination, gas separation, filtration and dialysis. The properties of the membranes vary depending on the morphology of the membrane i.e. properties such as symmetry, pore shape, pore size and the chemical nature of the polymeric material used to form the membrane.
Different membranes can be used for specific separation processes, including microfiltration, ultrafiltration and reverse osmosis. Microfiltration and ultrafiltration are pressure driven processes and are distinguished by the size of the particle or molecule that the membrane is capable of retaining or passing. Microfiltration can remove very fine colloidal particles in the micrometer and submicrometer range. As a general rule, microfiltration can filter particles down to 0.05 μm, whereas ultrafiltration can retain particles as small as 0.01 μm and smaller. Reverse Osmosis operates on an even smaller scale.
Microporous phase inversion membranes are particularly well suited to the application of removal of viruses and bacteria.
A large surface area is needed when a large filtrate flow is required. A commonly used technique to minimize the size of the apparatus used is to form a membrane in the shape of a hollow porous fibre. A large number of these hollow fibres (up to several thousand) are bundled together and housed in modules. The fibres act in parallel to filter a solution for purification, generally water, which flows in contact with the outer surface of all the fibres in the module. By applying pressure, the water is forced into the central channel, or lumen, of each of the fibres while the microcontaminants remain trapped outside the fibres. The filtered water collects inside the fibres and is drawn off through the ends.
The fibre module configuration is a highly desirable one as it enables the modules to achieve a very high surface area per unit volume.
In addition to the arrangement of fibres in a module, it is also necessary for the polymeric fibres themselves to possess the appropriate microstructure to allow microfiltration to occur.
Desirably, the microstructure of ultrafiltration and microfiltration membranes is asymmetric, that is, the pore size gradient across the membrane is not homogeneous, but rather varies in relation to the cross-sectional distance within the membrane. Hollow fibre membranes are preferably asymmetric membranes possessing tightly bunched small pores on one or both outer surfaces and larger more open pores towards the inside edge of the membrane wall.
This microstructure has been found to be advantageous as it provides a good balance between mechanical strength and filtration efficiency.
As well as the microstructure, the chemical properties of the membrane are also important. The hydrophilic or hydrophobic nature of a membrane is one such important property.
Hydrophobic surfaces are defined as “water hating” and hydrophilic surfaces as “water loving”. Many of the polymers used to cast porous membranes are hydrophobic polymers. Water can be forced through a hydrophobic membrane by use of sufficient pressure, but the pressure needed is very high (150-300 psi), and a membrane may be damaged at such pressures and generally does not become wetted evenly.
Hydrophobic microporous membranes are typically characterised by their excellent chemical resistance, biocompatibility, low swelling and good separation performance. Thus, when used in water filtration applications, hydrophobic membranes need to be hydrophilised or “wet out” to allow water permeation. Some hydrophilic materials are not suitable for microfiltration and ultrafiltration membranes that require mechanical strength and thermal stability since water molecules can play the role of plasticizers.
Currently, poly(tetrafluoroethylene) (PTFE), polyethylene (PE), polypropylene (PP) and poly(vinylidene fluoride) (PVDF) are the most popular and available hydrophobic membrane materials. PVDF exhibits a number of desirable characteristics for membrane applications, including thermal resistance, reasonable chemical resistance (to a range of corrosive chemicals, including sodium hypochlorite), and weather (UV) resistance.
While PVDF has to date proven to be the most desirable material from a range of materials suitable for microporous membranes, the search continues for membrane materials which will provide better chemical stability and performance while retaining the desired physical properties required to allow the membranes to be formed and worked in an appropriate manner.
In particular, a membrane is required which has a superior resistance (compared to PVDF) to more aggressive chemical species, in particular, oxidising agents and to conditions of high pH i.e. resistance to caustic solutions. In particular with water filtration membranes, chlorine resistance is highly desirable. Chlorine is used to kill bacteria and is invariably present in town water supplies. Even at low concentrations, a high throughput of chlorinated water can expose membranes to large amounts of chlorine over the working life of a membrane can lead to yellowing or brittleness which are signs of degradation of the membrane.
Microporous synthetic membranes are particularly suitable for use in hollow fibres and are produced by phase inversion. In this process, at least one polymer is dissolved in an appropriate solvent and a suitable viscosity of the solution is achieved. The polymer solution can be cast as a film or hollow fibre, and then immersed in precipitation bath such as water. This causes separation of the homogeneous polymer solution into a solid polymer and liquid solvent phase. The precipitated polymer forms a porous structure containing a network of uniform pores. Production parameters that affect the membrane structure and properties include the polymer concentration, the precipitation media and temperature and the amount of solvent and non-solvent in the polymer solution. These factors can be varied to produce microporous membranes with a large range of pore sizes (from less than 0.1 to 20 μm), and possess a variety of chemical, thermal and mechanical properties.
Hollow fibre ultrafiltration and microfiltration membranes are generally produced by either diffusion induced phase separation (the DIPS process) or by thermally induced phase separation (the TIPS process).
Determining the appropriate conditions for carrying out the TIPS process is not simply a matter of substituting one polymer for another. In this regard, casting a polymeric hollow fibre membrane via the TIPS process is very different to casting or extruding a bulk item from the same material. The TIPS procedure is highly sensitive, each polymer requiring careful selection of a co-solvent, a non-solvent, a lumen forming solvent or non-solvent, a coating solvent or non-solvent and a quench, as well as the appropriate production parameters, in order to produce porous articles with the desired chemically induced microstructure in addition to the overall extruded high fibre structure.
The TIPS process is described in more detail in PCT AU94/00198 (WO 94/17204) AU 653528, the contents of which are incorporated herein by reference.
The quickest procedure for forming a microporous system is thermal precipitation of a two component mixture, in which the solution is formed by dissolving a thermoplastic polymer in a solvent which will dissolve the polymer at an elevated temperature but will not do so at lower temperatures. Such a solvent is often called a latent solvent for the polymer. The solution is cooled and, at a specific temperature which depends upon the rate of cooling, phase separation occurs and the polymer rich phase separates from the solvent.
All practical thermal precipitation methods follow this general process which is reviewed by Smolders et al in Kolloid Z.u.Z Polymer, 43, 14-20 (1971). The article distinguishes between spinodal and binodal decomposition of a polymer solution.
The equilibrium condition for liquid-liquid phase separation is defined by the binodal curve for the polymer/solvent system. For binodal decomposition to occur, the solution of a polymer in a solvent is cooled at an extremely slow rate until a temperature is reached below which phase separation occurs and the polymer rich phase separates from the solvent.
It is more usual for the phases not to be pure solvent and pure polymer since there is still some solubility of the polymer in the solvent and solvent in the polymer, there is a polymer rich phase and a polymer poor phase. For the purposes of this discussion, the polymer rich phase will be referred to as the polymer phase and the polymer poor phase will be referred to as the solvent phase.
When the rate of cooling is comparatively fast, the temperature at which the phase separation occurs is generally lower than in the binodal case and the resulting phase separation is called spinodal decomposition.
According to the process disclosed in U.S. Pat. No. 4,247,498, the relative polymer and solvent concentrations are such that phase separation results in fine droplets of solvent forming in a continuous polymer phase. These fine droplets form the cells of the membrane. As cooling continues, the polymer freezes around the solvent droplets.
As the temperature is lowered, these solubilities decrease and more and more solvent droplets appear in the polymer matrix. Syneresis of the solvent from the polymer results in shrinkage and cracking, thus forming interconnections or pores between the cells. Further cooling sets the polymer. Finally, the solvent is removed from the structure.
Known thermal precipitation methods of porous membrane formation depend on the polymer rich phase separating from the solvent followed by cooling so that the solidified polymer can then be separated from the solvent. Whether the solvent is liquid or solid when it is removed from the polymer depends on the temperature at which the operation is conducted and the melting temperature of the solvent.
True solutions require that there be a solvent and a solute. The solvent constitutes a continuous phase and the solute is uniformly distributed in the solvent with no solute-solute interaction. Such a situation is almost unknown with the polymer solutions. Long polymer chains tend to form temporary interactions or bonds with other polymer chains with which they come into contact. Polymer solutions are thus rarely true solutions but lie somewhere between true solutions and mixtures.
In many cases it is also difficult to state which is the solvent and which is the solute. In the art, it is accepted practice to call a mixture of polymer and solvent a solution if it is optically clear without obvious inclusions of either phase in the other. By optically clear, the skilled artisan will understand that polymer solutions can have some well known light scattering due to the existence of large polymer chains. Phase separation is then taken to be that point, known as the cloud point, where there is an optically detectable separation. It is also accepted practice to refer to the polymer as the solute and the material with which it is mixed to form the homogeneous solution as the solvent.
In the present case the inventors have sought to find a way to prepare membranes without the use of highly toxic solvents, and in particular, to prepare hollow fibre poly(ethylene chlorotrifluoroethylene) membranes. Poly(ethylene chlorotrifluoroethylene), is a 1:1 alternating copolymer of ethylene and chlorotrifluoroethylene, and having the following structure:
—(—CH 2 —CH 2 —CFCl—CF 2 —) n —
While the embodiments of the invention are described herein with respect to HALAR® fluoropolymer, this term is used herein to encompass fluoropolymer equivalents, such as
—(—(CH 2 —CH 2 —) m —CX 2 —CX 2 —)—
wherein each X is independently selected from F or Cl, and where m is chosen so as to be between 0 and 1, so as to allow the ethylene portion of the polymer to range from 0 to 50%. An example of a HALAR® fluoropolymer equivalent is PCTFE.
It has been known for some time to produce flat sheet poly(ethylene chlorotrifluoroethylene) membranes, and the processes are disclosed in U.S. Pat. No. 4,702,836, for example. The previous methods were not amenable to producing hollow fibres and moreover, utilised solvents which are highly toxic with high environmental impact, such as 1,3,5-trichlorobenzene, dibutyl phthalate and dioctyl phthalate.
The properties of poly(ethylene chlorotrifluoroethylene) make it highly desirable in the field of ultrafiltration and microfiltration. In particular, poly(ethylene chlorotrifluoroethylene) has extremely good properties in relation to its resistance both to chlorine and to caustic solutions, but also to ozone and other strong oxidising agents. While these desiderata have been established for some time, it was hitherto unknown how to fulfill the long felt need to make hollow fibre membranes from such a desirable compound. Further, a disadvantage in relation to the existing prepararatory methods for HALAR® fluoropolymer flat sheet membranes is that they require the use of highly toxic solvents or solvents that are of dubious safety at the very least. For instance, the conventional state of the art is that the solvents needed are aromatic solvents such as dibutyl phthalate (DBP), dioctyl phthalate (DOP) and 1,3,5-trichlorobenzene (TCB). Such difficult solvents are required due to the chemical stability of poly(ethylene chlorotrifluoroethylene) and its resistance to most common solvents below 150° C.
It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative, particularly in terms of methods of production.
SUMMARY OF THE INVENTION
According to a first aspect, the invention provides a porous polymeric membrane including poly(ethylene chlorotrifluoroethylene) and formed without the use of toxic solvents, or solvents of dubious or unproven safety.
The membranes may be preferably flat sheet, or, more preferably hollow fibres.
Preferably, the porous polymeric membrane is formed by the TIPS (thermally induced phase separation) process and has an asymmetric pore size distribution. Most preferably, the fluoropolymer ultrafiltration or microfiltration membrane has an asymmetric cross section, a large-pore face and a small-pore face.
Preferably, the porous polymeric Halar membrane has pore size is in the range 0.01 μm to 20 μm. Pore size can be determined by the so called bubble point method.
According to a second aspect, the invention provides a porous polymeric membrane formed from poly(ethylene chlorotrifluoroethylene) and prepared from a solution containing one or more compounds according to formula I or formula II:
wherein R 1 , R 2 and R 3 are independently methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl.
R 4 is H, OH, COR 5 , OCOR 5 , methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl, methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy or other alkoxy,
R 5 is methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl.
Preferably, R 1 , ═R 2 ═R 3 =ethyl and R 4 ═H.
Preferably, the pore controlling agent is citric acid ethyl ester (CITROFLEX®2) or glycerol triacetate.
The above compounds may be used as polymer solvents, coating agents or both, and may be used alone, in mixtures of the above compounds, or in conjunction with other appropriate agents.
The porous polymeric membranes of the present invention may include one or more materials compatible with poly(ethylene chlorotrifluoroethylene).
The porous polymeric membranes ultrafiltration or microfiltration of the present invention may be either hydrophobic or hydrophilic, and may include other polymeric materials compatible with poly(ethylene chlorotrifluoroethylene). Additional species adapted to modify the chemical behaviour of the membrane may also be added. In one highly preferred alternative, the porous polymeric membrane of the present invention further including modifying agent to modify the hydrophilicity/hydrophobicity balance of the membrane. This can result in a porous polymeric membrane which is hydrophilic or alternatively, a porous polymeric membrane which is hydrophobic.
According to a third aspect, the invention provides a porous polymeric membrane formed from poly(ethylene chlorotrifluoroethylene) and incorporating a leachable agent.
In one preferred embodiment, the leachable agent is silica.
Preferably, the silica is present in an amount of from 10 to 50 wt % of the final polymer, and more preferably around 30%. The silica may be hydrophobic silica or hydrophilic silica. Highly preferred are fumed silica's such as the hydrophilic AEROSIL® 200 silica and the hydrophobic AEROSIL® R 972 silica.
Preferably, the porous polymeric membranes of the present invention have one or more of the following properties: high permeability (for example, greater than 1000 LMH/hr@ 100 KPa), good macroscopic integrity, uniform wall thickness and high mechanical strength (for example, the breakforce extension is greater than 1.3N).
According to a fourth aspect, the present invention provides a method of making a porous polymeric material comprising the steps of: (a) heating a mixture comprising poly(ethylene chlorotrifluoroethylene) and a solvent system initially comprising a first component that is a latent solvent for poly(ethylene chlorotrifluoroethylene) and optionally a second component that is a non-solvent for poly(ethylene chlorotrifluoroethylene) wherein, at elevated temperature, poly(ethylene chlorotrifluoroethylene) dissolves in the solvent system to provide an optically clear solution, (b) rapidly cooling the solution so that non-equilibrium liquid-liquid phase separation takes place to form a continuous polymer rich phase and a continuous polymer lean phase with the two phases being intermingled in the form of bicontinuous matrix of large interfacial area, (c) continuing cooling until the polymer rich phase solidifies; and (d) removing the polymer lean phase from the solid polymeric material.
According to a fifth aspect, the invention provides a porous polymeric membrane formed from poly(ethylene chlorotrifluoroethylene) and containing silica and wherein said polymeric porous poly(ethylene chlorotrifluoroethylene) membrane has a coating of a coating agent including one or more compounds according to formula I or II:
wherein R 1 , R 2 and R 3 are independently methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl.
R 4 is H, OH, COR 5 , OCOR 5 , methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl, methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy or other alkoxy.
R 5 is methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl.
Preferably, R 1 , ═R 2 ═R 3 =ethyl and R 4 ═H.
Preferably, the pore controlling agent is an environmentally friendly solvent.
Preferably, the pore controlling agent is citric acid ethyl ester or glycerol triacetate.
According to a sixth aspect, the invention provides a method of manufacturing a microfiltration or ultrafiltration membrane including the step of casting a membrane from a polymer composition including poly(ethylene chlorotrifluoroethylene).
According to a seventh aspect, the invention provides a method of forming a hollow fibre membrane comprising: forming a blend of poly(ethylene chlorotrifluoroethylene) with a compatible solvent; forming said blend into a shape to provide a hollow fibre; contacting an internal lumen surface of said blend with a lumen forming fluid; inducing thermally induced phase separation in said blend to form a hollow fibre membrane; and removing the solvent from the membrane.
Preferably, the poly(ethylene chlorotrifluoroethylene) is present in the blend in an amount ranging from 14-25%, and most preferably around 16-23%. Preferably, the pore controlling agent is an environmentally friendly solvent, such as GTA or citric acid ethyl ester. Preferably, the lumen forming fluid is digol. In highly preferred embodiments, the process is conducted at elevated temperatures, preferably above 200° C., and more preferably above 220° C.
According to an eighth aspect, the invention provides a method of forming a hollow fibre fluoropolymer membrane comprising: forming a blend of poly(ethylene chlorotrifluoroethylene) with a compatible solvent; forming said blend into a shape to provide a hollow fibre; contacting an external surface of said blend with a coating fluid; contacting an internal lumen surface of said blend with a lumen forming fluid; inducing thermally induced phase separation in said blend to form a hollow fibre membrane; and extracting the solvent from the membrane.
Preferably, the coating is selected from one or more of GTA, citric acid ethyl ester and digol.
According to an ninth aspect, the invention provides a method of forming a hollow fibre membrane comprising: forming a blend of poly(ethylene chlorotrifluoroethylene) with a compatible solvent; suspending a pore forming agent in said blend; forming said blend into a shape to provide a hollow fibre; contacting an internal lumen surface of said blend with a lumen forming fluid; inducing thermally induced phase separation in said blend to form a hollow fibre membrane; and extracting the solvent from the membrane.
Preferably, the pore forming agent is a leachable pore forming agent, such as silica.
According to a tenth aspect, the invention provides a method of forming a hollow fibre membrane comprising: forming a blend of poly(ethylene chlorotrifluoroethylene) with a compatible solvent; suspending a pore forming agent in said blend; forming said blend into a shape to provide a hollow fibre; contacting an external surface of said blend with a coating fluid; contacting an internal lumen surface of said blend with a lumen forming fluid; inducing thermally induced phase separation in said blend to form a hollow fibre membrane; and extracting the solvent from the membrane.
Preferably the pore forming agent is a leachable pore forming agent, more preferably silica. The method may further include the step of leaching said leachable pore forming agent from said membrane. Preferably, the pore forming agent is a leachable silica, which is leached from the dope by caustic solution.
In certain preferred embodiments, the digol is used as a non-solvent and independently water is used as a quench fluid.
According to an eleventh aspect, the invention provides a method of forming a hollow fibre membrane comprising: forming a blend of poly(ethylene chlorotrifluoroethylene) with a compatible solvent; suspending a leachable pore forming agent in said blend; forming said blend into a shape to provide a hollow fibre; contacting an internal lumen surface of said blend with a lumen forming fluid; inducing thermally induced phase separation in said blend to form a hollow fibre membrane; extracting the solvent from the membrane; and leaching said leachable pore forming agent from said membrane.
According to a twelfth aspect, the invention provides a method of forming a hollow fibre membrane comprising: forming a blend of poly(ethylene chlorotrifluoroethylene) with a compatible solvent; suspending a leachable pore forming agent in said blend; forming said blend into a shape to provide a hollow fibre; contacting an external surface of said blend with a coating fluid; contacting an internal lumen surface of said blend with a lumen forming fluid; inducing thermally induced phase separation in said blend to form a hollow fibre membrane; extracting the solvent from the membrane; and leaching said leachable pore forming agent from said membrane.
Preferably, the pore forming agent is a leachable pore forming agent, such as silica, which is leached from the dope by caustic solution, preferably 5 wt %.
Preferably, digol is used as a non-solvent and independently water is used as a quench fluid.
According to a thirteenth aspect, the present invention provides the use of Halar for forming a hollow fibre ultrafiltration or microfiltration membrane.
According to a fourteenth aspect, the present invention provides method of forming a polymeric ultrafiltration or microfiltration membrane including the steps of: preparing a leachant resistant poly(ethylene chlorotrifluoroethylene) membrane dope; incorporating a leachable pore forming agent into the dope; casting a membrane; and leaching said leachable pore forming agent from said membrane with said leachant.
Preferably, the leachable pore forming agent is an inorganic solid with an average particle size less than 1 micron, and most preferably is leachable silica. In highly preferred embodiments, the silica is present in around 3-9%.
Preferably, the leachant is a caustic solution.
The invention also provides a porous polymeric poly(ethylene chlorotrifluoroethylene) microfiltration or ultrafiltration membrane when prepared by any of the preceding aspects.
According to a fifteenth aspect, the invention provides a microporous poly(ethylene chlorotrifluoroethylene) membrane prepared from an environmentally friendly solvent or mixture of environmentally friendly solvents.
Preferably, the membrane is a flat sheet or hollow fibre membrane.
Preferably, the flat sheet membrane is prepared from an environmentally friendly solvent or mixture of solvents containing one or more compounds according to the following formula:
wherein R 1 , R 2 and R 3 are independently methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl.
R 4 is H, OH, COR 5 , OCOR 5 , methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl, methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy or other alkoxy.
R 5 is methyl, ethyl, propyl, butyl, pentyl, hexyl or other alkyl.
Preferably, R 1 ═R 2 ═R 3 =ethyl and R 4 ═H.
Preferably, the pore controlling agent is citric acid ethyl ester or glycerol triacetate.
The term “environmentally friendly” as used herein refers to materials having a lesser or reduced effect on human health and the environment when compared with competing products or services that serve the same purpose. In particular, “environmentally friendly” refers to materials which have low toxicity to plants and animals, especially humans. Environmentally friendly also encompasses biodegradable materials.
Preferably, the environmentally friendly solvents used in the present invention are not recognised as hazardous to the health of humans or other organisms, either when subject exposure is acute (short term/high dose) or long term (typically at a lower dose).
It is preferable, that the acute toxicity below, ie it is preferable if the solvents have a high LD50. For example, the LD50 of glycerol triacetate in rodents is around 3000 mg/kg bodyweight, whereas in the case of 1,3,5-trichlorobenzene, the LD50 is as low as 300-800 mg/kg. Preferably in the present invention, the LD50 is above 1000 mg/kg, and more preferably above 2000 mg/kg.
However, as well as acute toxicity, it is also highly desirable that the solvents do not show long term, low level exposure effects, and are not carcinogenic, mutagenic or teratogenic. This will not so much be reflected by their LD50's (although these are a factor), but reflects factors such as the ability of the solvent to bioaccumulate as well as its inherent toxic and mutagenic properties. Preferably, the solvents of the present invention do not bioaccumulate. In this regard, the biodegradability of the solvent is important, and high biodegradability is preferred.
It is also necessary to consider other ecotoxicological effects such as the toxicity to non-humans/non-mammals, and factors such as whether the solvent is an ozone depleting compound.
In terms of structural considerations, the type of structural features which may be found in suitable environmentally friendly solvents include the presence of degradable groups, eg hydrolysable groups, such as esters, (especially when these result in much smaller molecules, such as C4 or less); absence of halogens (such as chlorine); and the absence of aromatic rings. The preferred solvents of the present invention exhibit these three favourable characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a and 1 b are diagrams of alternative TIPS processes used to prepare HF membranes
FIGS. 2 a and 2 b are Scanning Electron Micrographs of the membranes of the present invention.
FIGS. 3 a and 3 b are Scanning Electron Micrographs of the membranes of the present invention.
FIG. 4 shows the results of IGG filtration using the membranes of the present invention.
FIG. 5 is a summary of membrane production.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The TIPS process is described in more detail in PCT AU94/00198 (WO 94/17204) AU 653528, the contents of which are incorporated herein by reference. The current method used to prepare the membranes of the present invention is described herein in simplified form.
In one preferred form of the invention, poly (ethylene chlorotrifluoroethylene) is formed as a hollow fibre. The poly (ethylene chlorotrifluoroethylene) is dissolved in a suitable solvent and then passed through an annular co-extrusion head.
There are two possible ways to conduct the methods of the present invention in relation to hollow fibres. One is via a coextrusion head having three concentric passageways, as shown in cross section FIG. 1 b , the other is via a quadruple co-extrusion head having four concentric passageways is shown in cross section in FIG. 1 a . The principle is broadly the same in both cases, except for the way the quench fluid is contacted with the fibre.
In both cases, the axial passageway 1 may contain a lumen forming fluid 11 . The first outwardly concentric passageway 2 contains a homogenous mixture of the polymer and solvent system 12 to form the membrane, the next outwardly concentric passageway 3 has a coating fluid 13 . In the case of the triple extrusion head, the quench is a bath either directly adjacent the extrusion head or slightly spaced below it with an intermediate air gap. In the quadruple extrusion head, the outermost passageway 4 applies a quench fluid 14 to the fibre.
Under carefully thermally controlled conditions, the lumen forming fluid, the membrane forming solution and the coating fluid are coating fluid are contacted with a quench fluid at a predetermined temperature (and flow rate, if the quench is applied by means of an outermost concentric passageway). The poly (ethylene chlorotrifluoroethylene) solution comes into contact with the lumen forming fluid on the inside of the hollow fibre and with the coating fluid and/or quench bath solution on the outside of the hollow fibre.
The lumen and coating fluids contain one or more components of the solvent system, alone or in combination with other solvents, in selected proportions (the first component may be absent). The composition of the coating and lumen fluids predetermine the pore size and frequency of pores on the membrane surfaces.
Each fluid is transported to the extrusion head by means of individual metering pumps. The three components are individually heated and are transported along thermally insulated and heat traced pipes. The extrusion head has a number of temperature zones. The lumen fluid, membrane forming solution (dope) and coating fluid are brought to substantially the same temperature in a closely monitored temperature zone where the dope is shaped. As mentioned above, the exact nature of the quench depends on whether the quadruple or triple extrusion head is used. In the quadruple, the quench fluid is introduced via an outer concentric passageway. The fibre may travel down the quench tube at a significantly different linear speed from the quench fluid. The fibre may then pass into a further quantity of quenching fluid if desired.
In the triple extruder system, the fibre passes out of the die; which may be optionally in the shape of a stem to assist in determining fibre structure. The fibre may pass through an optional air gap before passing into a quench bath. Most fibres disclosed herein were prepared by the triple extrusion head, as will be clear by the inclusion of an air gap distance in the production parameters.
When the quench fluid is contacted with the dope, the dope undergoes non-equilibrium liquid-liquid phase separation to form a bicontinuous matrix of large interfacial area of two liquids in which the polymer rich phase is solidified before aggregated separation into distinct phases of small interfacial area can take place.
Preferably, any air, gas or vapour (not being a gas or vapour that serves as the lumen fluid), is excluded during extrusion and the fibre is stressed axially to stretch it by a factor ranging from 1.5 to 5, thereby elongating the surface pores.
The hollow fibre membrane leaves the extrusion head completely formed and there is no need for any further formation treatment except for removing the solvent system from the membrane in a post-extrusion operation that is common to membrane manufacturing process. In a preferred method, an appropriate solvent that does not dissolve the polymer but is miscible with the dope solvents is used to remove the solvent system for the polymer from the finished membrane.
The lumen forming fluid may be selected from a wide variety of substances such as are disclosed herein. The same substance may be used as the coating and quenching liquids. Water or virtually any other liquid may be used as the quench liquid. Water is used if a highly asymmetric structure is desired.
Asymmetric membranes can on rare occasions result from the TIPS process. The rate and speed of de-mixing occurs faster at the outer surface of the membrane and slower further away from the interface. This results in a pore size gradient with smaller pores at the surface and larger pores further inwards. The pores at the interface which in a hollow fibre are the outer layer of the fibre and the wall of the lumen may, in some circumstances, be so small that a “skin” region occurs. This is about one micron thick and is the critical region for filtration. Thus, the outside of the fibre is small pored whereas the centre of the polymeric region has large pore size.
The initial poly (ethylene chlorotrifluoroethylene) membrane trials were conducted by extrusion from small scale apparatus into a water quench, using either glycerol triacetate (GTA) or citric acid ethyl ester as the solvent. The structure of the membranes as observed by SEM appeared to be excellent, although there was some degree of skinning. The membrane prepared from citric acid ethyl ester appeared the most promising and had a relatively open skin with a number of larger holes.
A poly(ethylene chlorotrifluoroethylene) membrane was prepared by extrusion in the manner described above for the TIPS process. The poly (ethylene chlorotrifluoroethylene) membranes were initially prepared without the use of a coating fluid, using GTA (Table 1) or citric acid ethyl ester (Table 2) as solvent.
TABLE 1
Uncoated Poly(Ethylene Chlorotrifluoroethylene) membrane -
GTA Solvent
Parameter
Value
Solvent
100% Glycerine Triacetate
(GTA)
Lumen
100% Digol
Poly (ethylene chlorotrifluoroethylene)
24%
Concentration
Barrel Temperature
230° C.
Solvent injectors
230° C.
Throughput
100 cc/min
Screw speed
250 rpm
Die Temperature
212° C.
The dope was completely clear and homogeneous, indicating complete solubility of the poly(ethylene chlorotrifluoroethylene) in the GTA at 230° C. The dope solidified under ambient conditions after approximately 5 seconds. The fibre was extruded through a die at a temperature of 212° C. into a water quench. The air gap was approximately 15 mm and the lumen forming liquid was diethylene glycol (digol).
Selecting a die temperature which is too low can lead to pulsing of the fibre and blockages in the die. HALAR® fluoropolymer melts at 240° C. and dissolves in GTA between 210° C. and 220° C. with a cloud point around 215° C. The solvent was varied to CITROFLEX® 2 citric acid ethyl ester as per Table 2.
TABLE 2
Uncoated Poly(Ethylene Chlorotrifluoroethylene) Membrane -
CITROFLEX ® 2 Solvent
Parameter
Value
Solvent
100% CITROFLEX ® 2
Lumen
100% Digol
Poly (ethylene chlorotrifluoroethylene)
24%
Concentration
Barrel Temperature
230° C.
Solvent injectors
230° C.
Throughput
100 cc/min
Screw speed
250 rpm
Die Temperature
212° C.
The dope was completely clear and homogeneous as with the GTA mixture, indicating complete solubility of the polymer in CITROFLEX® 2 citric acid ethyl ester at 230° C. The dope had a consistency slightly better than that of the GTA dope and also solidified under ambient conditions after approximately 5 seconds.
When CITROFLEX® 2 citric acid ethyl ester was used as the solvent, it was necessary to add extra heat to the die to raise the temperature to sufficient levels to prevent blockages. The fibre was eventually extruded through a die at a temperature of approximately 212° C. into a water quench. The air gap was approximately 15 mm and the lumen liquid was diethylene glycol (digol).
The SEMs showed the structure of the surface and of the cross-section of both hollow fibre poly(ethylene chlorotrifluoroethylene) membranes prepared using GTA and CITROFLEX® 2 citric acid ethyl ester to have adequate pore formation and structure. The fibres were also surprisingly strong and ductile, with a large degree of flexibility.
The procedure was further modified by the use of a coating on the outside of the fibre. The use of coating compositions in the preparation of the fluoropolymer membranes was found to enhance the permeability (2200 LMH) and improve the bubble point (490 kPa) of the resultant membranes. The process parameters are shown below in Table 3.
TABLE 3
Coated Poly(Ethylene Chlorotrifluoroethylene) Membrane -
Various Solvents
Parameter
Value
Solvent
GTA
Coating
GTA
CITROFLEX ® 2
Digol
Lumen
100% Digol
Polymer Concentration
21%
Barrel Temperature
230° C.
Solvent injectors
230° C.
Throughput
100 cc/min
Screw speed
250 rpm
Die Temperature
200° C.
As previously, the dope was clear and homogeneous, was of a good consistency and solidified under ambient conditions after approx. 5 seconds. The fibre was extruded through a die at a temperature of approximately 200° C. into a water quench. The air gap was approximately 15 mm and the lumen liquid was diethylene glycol (digol).
It was necessary to ensure that the die temperature and a regular coating flow were maintained. Irregular flow was minimised or eliminated by degassing the coating and lumen vessels prior to use. Heated lines were installed for the coating and lumen fluids to help maintain die temperature. Extra insulation was also used, as maintaining an adequate temperature is required in order to produce a hollow poly (ethylene chlorotrifluoroethylene) fibre of consistent quality.
Two different trials were performed: GTA coating and CITROFLEX® 2 citric acid ethyl ester coating. An uncoated sample was produced for comparison (Table 4).
TABLE 4
Coated Poly(Ethylene Chlorotrifluoroethylene) Hollow Fibre
Membrane Performance
No
GTA
CITROFLEX ® 2
Parameter
Coating
Coating
Coating
% poly(ethylene
21
21
21
chlorotrifluoroethylene)
Coating Flow (cc/min)
0
10
10
Lumen Flow (cc/min)
5
5
5
Permeability (LMH @ 100 kPa)
—
2294
—
Bubble Point (kPa)
—
490
—
Break Extension (%)
—
92.9
—
Break Force (N)
—
1.35
—
Force/unit area (MPa)
—
4.6
—
Fibre OD/ID (μm)
856/469
766/461
—
As was apparent from the SEMs of the sample, the sample with no coating had an impermeable skin, hence the absence of a result for permeability. The skin also has the effect of increasing break extension (BE) and break force (BF) artificially therefore these test were not performed either.
The results from the GTA coated samples showed that permeability was high, as was break extension and force. In some cases, the photograph of the cross section of the GTA coated sample showed some small “holes”, probably caused by bubbles in the dope.
The high bubble point for the GTA sample indicates that many smaller pores rather than a smaller number of larger pores provide the high flow. The CITROFLEX® 2 citric acid ethyl ester coated membrane can be seen in the SEM's to have a good pore structure.
In order to produce membranes with a controlled density surface skin and having a more hydrophilic nature, silica was added to the dope with the intention of subsequently leaching the silica out of the formed membrane matrix by the use of a caustic solution.
A hydrophilic silica, AEROSIL® R 972 was tested as an additives to the poly (ethylene chlorotrifluoroethylene) membrane mixture. The dope was cast into a hollow fibre membrane, and the resultant hollow fibre membranes were quenched in water.
Once the membranes had been cast, a portion thereof was leached in a 5% aqueous caustic solution at room temperature for 14 hours.
After the membranes were cast, and prior to leaching, the membranes were examined using scanning electron microscopy. The structures were generally extremely promising with the surface of the sheets completely open and totally free of any skin.
The addition of the silica produced a hydrophilic membrane with a highly porous structure.
Subsequently placing the sample in caustic soda to leach the silica provided a dramatic opening up in the membrane structure even further. The result of the leaching was a change in the cross-section from a conglomerate-like structure to the more traditional lace or sponge-like formation. The leaching with caustic soda provided a membrane of good open structure.
The optimal dope for forming a TIPS poly (ethylene chlorotrifluoroethylene) lymer appears to be require the incorporation of 10-50 wt % silica relative to the polymer.
A number of hollow fibre membranes were prepared from the above dope. The wetting characteristics were as desired and the membrane structure showed an extremely open surface. While 3-6% silica was used in the present invention, it will be appreciated that the quantity can vary significantly without departing from the present inventive concept.
Leaching the silica from the membranes had increased effect on the permeability and pore size of the hollow fibres without altering the desirable physical properties of the membrane.
A long leaching time is not necessarily required and can be incorporated in the production process as a post-treatment of the final modular product. The leaching process can be carried out at any time, however there is an advantage to postponing the leaching process as long as possible, since any damage to the surface of the fibres during handling can be overcome by leaching which physically increases the porosity of the membrane.
SEM analysis of the membranes showed a high degree of asymmetry. Asymmetry is defined as a gradual increase in pore size throughout the membrane cross-section, such that the pores at one surface of the hollow fibre are larger than the other. In this case, the pore size increase was seen from the outer surface where the pores were smallest (and a quite dense surface layer was present) to the inner surface where the pores were significantly larger than those on the outer surface.
As well as silica, the leaching process allows for the introduction of other functionalities into the membrane, such as introducing hydrolysable esters to produce groups for anchoring functional species to membranes.
The leaching process has the capacity to maintain the hydrophilic character of a membrane after leaching. Again, without wishing to be bound by theory, the silica particles have a size in the order of nanometres so consequently the silica disperses homogeneously throughout the polymer solution. When the polymer is precipitated in the spinning process, there is a degree of encapsulation of the SiO 2 particles within the polymer matrix. Some of the particles (or the conglomerates formed by several silica particles) are wholly encapsulated by the precipitating polymer, some are completely free of any adhesion to the polymer (i.e. they lie in the pores of the polymer matrix) and some of the particles are partially encapsulated by the polymer so that a proportion of the particle is exposed to the ‘pore’ or to fluid transfer.
When contacted with caustic, it is believed that these particles will be destroyed from the accessible side, leaving that part of the particle in touch with the polymer matrix remaining. The remainder of the silica particle adheres to the polymer matrix by hydrophobic interaction and/or mechanical anchoring. The inside of the particle wall is hydrophilic because it consists of OH groups attached to silica. Because the silica is connected to hydrophobic groups on the other side, it cannot be further dissolved.
Thus when the membranes are treated with caustic solution, the free unencapsulated SiO 2 reacts to form soluble sodium silicates, while the semi-exposed particles undergo a partial reaction to form a water-loving surface (bearing in mind that given the opportunity, such particles would have dissolved fully). It is believed that the pores in the polymer matrix formed during the phase inversion stage yet filled with SiO 2 particles are cleaned out during leaching, giving a very open, hydrophilic membrane.
Poly (ethylene chlorotrifluoroethylene) Membranes incorporating 3% AEROSIL® R 972 fumed silica into the membrane were prepared by the TIPS process. The process parameters are given in Table 5. The poly (ethylene chlorotrifluoroethylene) fibre sample was then placed in an aqueous solution of 5 wt % caustic to leach the silica from the membrane. The best result in terms of permeability was the citric acid ethyl ester coated sample (11294 LMH) but had a low bubble point (110 kPa). The best result in terms of bubble point was the GTA coated sample (150 kPa).
TABLE 5
Coated Membranes With Silica
Parameter
Value
Solvent
GTA
Coating
None
GTA
Digol
CITROFLEX ® 2
Lumen
100% Digol
Polymer
21%
Concentration
Additives
3% (of dope) AEROSIL ® R 972 silica delivered
as a slurry in GTA
Barrel
230° C.
Temperature
Solvent
230° C.
injectors
Throughput
100 cc/min
Screw speed
1250 rpm
Die
200° C.
Temperature
The dope was similar to that produced in the earlier trials. The most obvious difference was in opacity—with the silica included the dope was a cloudy white colour.
The fibre was extruded through a die at a temperature of approx. 200° C. into a water quench. The air gap was approximately 15 mm and the lumen liquid was diethylene glycol (digol).
Several different samples were taken. Some had no coating, others had GTA, Digol and citric acid ethyl ester coatings applied at two different production rates (30 and 60 m/min). The production parameters are shown in Table 6.
TABLE 6
Coated Membranes With Silica
No
Parameter
Coating
GTA
Digol
CITROFLEX ® 2
% Polymer
21
21
21
21
% Aerosil ®
3
3
3
3
R 972
Coating Flow
0
10
10
10
(cc/min)
Lumen Flow
5
5
5
5
(cc/min)
Permeability
0
1354
>1564
3296
(LMH@100 kPa)
Bubble Point (kPa)
0
238
>50
155
Break Extension
—
118
52.3
71.1
(%)
Break Force (N)
—
1.81
1.30
0.86
Force/unit area
—
3.63
3.74
4.67
(MPa)
Fibre OD/ID (μm)
624/356
968/550
783/414
614/385
The SEMs show that even with silica in the membrane the use of no coating agent resulted in the formation of a surface similar to a hollow fibre cast without silica. The appearance of the surfaces of the GTA and citric acid ethyl ester hollow fibre membranes are similar, but the citric acid ethyl ester coating gives a more open surface. This openness is reflected in the permeability and bubble point—the fibres coated with citric acid ethyl ester have a much lower bubble point and a much higher permeability than the GTA coated samples. The GTA and citric acid ethyl ester coated membranes with silica had a permeability close to that of the corresponding hollow fibre membrane samples prepared without added silica.
The Digol coated samples have a very rough and inconsistent surface, as shown by the poor bubble point.
The samples described herein were are all prepared at a 30 m/min production rate. However, no significant difference was observed between 30, 60 and 100 m/min production rates in casting any of the samples.
The samples contain silica that can be leached from the fibres by the use of caustic soda (sodium hydroxide). Thus the effect upon the flow rate and bubble point was determined by leaching an uncoated sample, a GTA coated sample and a citric acid ethyl ester coated sample in 5 wt % aqueous caustic solution at room temperature (23° C.). The Digol sample was omitted from this process due to its poor properties. Table 7 below gives fibre results and the SEMs of the leached fibres follow.
TABLE 7
Results for Leached Silica Poly(Ethylene Chlorotrifluoroethylene)
Fibres
Parameter
No Coating
GTA
CITROFLEX ® 2
% Polymer
21
21
21
% AEROSIL ® R 972
3
3
3
Coating Flow (cc/min)
0
10
10
Lumen Flow (cc/min)
5
5
5
Permeability
—
5867
11294
(LMH@100 kPa)
Bubble Point (kPa)
—
150
107
Break Extension (%)
—
115
81.0
Break Force (N)
—
1.67
0.98
Force/unit area (MPa)
—
3.36
5.43
Fibre OD/ID (μm)
624/356
968/550
614/385
Post-leaching SEMs of the fibres show some very impressive structures. All of the fibre cross sections are very open and in the case of the sample without coating, some asymmetry. The uncoated sample did not generate surface pores even after 5 days of leaching in the case of 3% silica, although this may be overcome by incorporating a higher silica content in the dope mixture. The surfaces of any fibres are not dramatically altered after leaching, but there is a significant change in the porosity and bubble point of the fibres.
The citric acid ethyl ester coated samples post-leaching increased in flow by nearly 350% (3296 to 11294 LMH) but the bubble point of the fibres while already low dropped by 31% (154 down to 107 kPa). This is consistent with the SEMs. The GTA samples have been consistent with these results; the sample with silica (pre-leaching) has lost a portion of its high bubble point (490 down to 238 kPa) whereas permeability is relatively unchanged with the addition of silica—as would have been expected for the citric acid ethyl ester sample.
Post-leaching however gave a dramatic 320% increase in the flow (1354 up to 5687 LMH) but a slightly larger drop in the bubble point of 37% (238 down to 150 kPa).
The mean of the break extension (BE) and break force (BF) results for the GTA and for the citric acid ethyl ester coated samples were unchanged after 30-40 hrs leaching in 5% NaOH at room temperature. This shows the polymer and resulting membrane resist caustic attack well.
The use of 3% silica was not sufficient to produce a hydrophilic membrane. However it nevertheless opens up the membrane structure and improve flows.
With higher silica content, up to around 6%, the flow and bubble point do not change dramatically from the results achieved with 3% silica because the presence of the silica is most likely what induces the changes in the membrane structure, not these quantities. The surface of the fibre is also modified to get a better retention.
The use of post treatment agents in modifying the properties of ultrafiltration membranes is known. One such post treatment, involving soaking the fluoropolymer fibres in 50 wt % aqueous glycerol solution for 24 h was conducted. The results shown below in Table 8 compare poly(ethylene chlorotrifluoroethylene) fibres otherwise identical apart from the glycerol soak. Soaking was seen to dramatically increase the permeability of the membrane, from being impermeable before treatment to having a permeability of 138 Lm −2 h −1 at 100 Kpa.
TABLE 8
Post Soaking in Glycerol
poly(ethylene
chlorotrifluoroethylene)
poly(ethylene chlorotrifluoroethylene
Parameter
No Post Treatment
50% Aqueous Glycerol 24 h
Solvent
100% GTA
100% GTA
Coating
100% GTA
100% GTA
% Polymer
21
21
Coating Flow Rate (cc/min)
2.5
2.5
Lumen Flow Rate (cc/min)
5
5
Haul Off (m/min)
80
80
Permeability (Lm −2 h −1 )@100 kpa
No flow
138
Water Bubble Point (kPa)
>660
>660
HFE Bubble Point (kPa)
—
200-250
Break Extension (%)
131
131
Break Force (N)
1.14
1.14
Force/Unit Area (Mpa)
6.82
6.82
Fibre OD/ID
539/278
539/278
The ability of membrane synthesis methods to be scaled up to production levels is important. The processes used to produce the large quantity of fibres must not only be operable on a small scale, they must also robust enough to be capable of being scaled up for use in a more typical production format, where solvent systems, die design and other production parameters need to be re optimised.
Trials were initially conducted on a system used for the commercial preparation of PVDF membranes by a TIPS process. The main differences were the use of polyethylene glycol (PEG200) as the quench fluid, rather than water.
The production parameters are as shown in the following Table 9.
TABLE 9
Production Parameters
Parameter
Value
Solvent
Citric acid ethyl ester
Coating
Citric acid ethyl ester
Lumen
100% Digol
Polymer concentration
21%
Barrel Temperature
230° C.
Solvent injectors
230° C.
Throughput
100 cc/min
Screw speed
250 rpm
Die Temperature
230° C.
As with the earlier trials, the extruder product was completely optically clear and homogeneous. The fibre was spun through a conventional TIPS die configurations at a temperature of 230° C., with a long (150 mm) stem in which citric acid ethyl ester coated the fibre. Finally the fibre emerged into a glass tube with polyethylene glycol as the quenching media. There was no air gap and the lumen liquid was diethylene glycol (digol).
The Trial produced fibers having the properties as shown in Table 10.
TABLE 10
CITROFLEX ® 2 Citric Acid Ethyl Ester Coated Fibers
Parameter
CITROFLEX ® 2 Coating
% Polymer
21
Coating Flow (cc/min)
10
Lumen Flow (cc/min)
5
Permeability (LMN@100 kPa)
2596
Bubble Point (kPa)
400
Break Extension (%)
145.8
Break Force (N)
1.3
Force/unit area (MPa)
8.38
Fibre OD/ID (um)
626/439
The SEMs show a fibre with a morphology exhibiting a uniform cross section with a slight degree of asymmetry. Also apparent is a very coarse pore structure on the surface, with skinned areas in between. These skinned areas probably account for the some of the high break extension (BE).
This trial demonstrates that different quench liquids can be used to produce a membrane with an acceptable structure. This is facilitated by the fact that the poly(ethylene chlorotrifluoroethylene) dope is very close to the cloud point, enabling the use of most types of non-solvent suitable to the process as a quench fluid giving slightly different structures. However as explained below, given the good structure with water—the cheapest non-solvent possible—it does not appear necessary to use another quench type.
A second trial was conducted with a similar dope using a triple head extruder as shown in FIG. 1 b . It is particularly preferred if the die is of a stem configuration. In FIG. 1 b , 13 is the coating fluid, 12 is the polymer solution (dope) and 11 is the lumen fluid. The stem can be of any length, but particularly is between 0.5 and 150 mm so that the coating covered the surface of the spun fibre evenly. The air gap, the distance between the die tip and the quench, can be any length but is most advantageously between 0 and 10 mm. The production parameters are shown in Table 11.
TABLE 11
Production Parameters
Parameter
Value
Solvent
GTA, Citric acid ethyl ester
Coating
GTA, Citric acid ethyl ester
Lumen
100% Digol
Polymer concentration
21%
Barrel Temperature
230° C.
Solvent injectors
230° C.
Throughput
100 cc/min
Screw speed
250 rpm
Die Temperature
230° C.
A plate was selected in preference to a long stem, the aim being to reduce the contact time between the coating fluid and the spun fibre. This was changed from 150 mm down to .about.5 mm of plate plus a very small air gap (.about.5 mm) so that the coating contact time is a small as possible. Following this the fibre entered directly into a water quench. Both the temperature of the coating fluid and the total contact time have a significant effect upon the structure of the fibre surface.
The SEMs showed the fibres to exhibit a difference in the surface structure compared to the initial production trial. The temperature of the die and coating were far more accurately controlled in the present trials. The coating temperature in the second trial was 230° C.+/−5° C., roughly 100° C. above the coating temperature for the previous trials. This difference has a dramatic effect upon the membrane surface structure.
Several different samples were taken with GTA and citric acid ethyl ester coating at two different production rates (30 and 60 m/min). Samples with GTA as a solvent were only taken with a GTA coating and likewise for citric acid ethyl ester. The results are shown in Table 12 and in the figures, which show representative examples of the membranes.
FIG. 2 a is a SEM which shows a cross section of a membrane prepared at a production rate of 60 m/min and coated with citric acid ethyl ester at a rate of 7.5 cc/min. FIG. 2 b shows a surface of the membrane.
FIG. 3 a is a SEM which shows a cross section of a membrane prepared at a production rate of 80 m/min and coated with GTA at a rate of 2.5 cc/min. FIG. 3 b shows a surface of the membrane.
TABLE 12
Production Properties of Coated Membranes
Parameter
Citric Acid Ethyl Ester
GTA
% Polymer
21
21
Coating
5
7.5
10
5
7.5.
1
2
5
2.5
2.5
Flow cc/min)
Lumen Flow
5
5
5
5
5
5
5
5
5
5
(cc/min)
Hauloff
60
60
60
80
80
60
60
60
80
100
(m/min)
Permeability
2633
3515
3161
2366
3090
38
19
64
—
57
(LM −2 H −1
@100 kPa
Bubble Point
250
350
400
350
350
>660
>660
>660
>660
>660
(kPa)
Break
66
53
29
42
57
185
184
168
131
132
Extension
(%)
Break Force
0.96
0.84
0.71
0.74
0.69
1.36
1.26
1.45
1.14
1.26
(N)
Force/unit
6.78
3.63
4.35
2.49
2.07
4.87
7.50
5.20
6.82
7.56
area (MPa)
Fibre OD/ID
652/378
621/336
570/380
660/376
561/326
710/356
760/393
697/393
539/278
534/271
(um)
Unlike the results obtained in the initial trial, the surfaces here due to GTA and citric acid ethyl ester are no longer similar and the citric acid ethyl ester coating gives a less open surface, contrary to previous trials. This is most likely due to the increase in coating temperature, since at higher temperatures both the citric acid ethyl ester and GTA become more aggressive as a solvent. The citric acid ethyl ester is most likely starting to re-dissolve some of the surface of the fibre before final precipitation is forced thus solidifying the structure.
The internal membrane structure also appears to be affected—the pores internally with citric acid ethyl ester as a solvent appear far coarser than those in the structure with a GTA solvent, whose pores appear very small and tightly packed. This is reflected in the permeability and bubble point—the fibres with citric acid ethyl ester as the solvent have a water bubble point much lower (250-400 kPa) but a much higher permeability (2500-3500 LMH) than the GTA coated samples. Given a regular surface on the citric acid ethyl ester the bubble point could be increased and the permeability enhanced.
The GTA samples are permeable however, at all coating flow rates. The GTA samples all had water bubble points far higher than the porometer could measure—but estimated to be in the region 800-900 kPa. These samples appear more clearly asymmetric than the samples with the citric acid ethyl ester as the solvent/coating.
The samples were tested for their capability for ultrafiltration. Initial tests showed a HFE bubble point of between 200 and 300 kPa. This correlates to a membrane with pores approaching—if not already within—the UF range. Consequently one sample was tested for protein retention with Immuno Gamma Globulin (IGG, MW=120 kD). The sample tested was the first of the GTA coated samples with 1 cc/min of coating. The sample retained >95% of IGG, close to a known UF membrane possessing a retention of 98%.
These fibre samples were not treated with glycerol, as is standard practice for UF-style membranes. Glycerol prevents very small pores from collapsing upon drying the membrane. Some similar samples to those UF tested were soaked in Glycerol before drying to prevent any possible pore collapse. This enhanced the permeability of the membrane up to 138 LMH from 0, and explains the poor permeabilities in the UF tests.
TABLE 13
UF Results
(i) GTA solvent/Coating
1 cc/min Coating
Sample
Time
LMH
Ethanol
02:49:04
6.17
Clean water
3:11:19.0
15.90
1
1:20:00.0
10.34
2
2:51:05.0
11.74
3
3:41:04.0
12.36
FIG. 4 shows protein retention over time on a poly(ethylene chlorotrifluoroethylene) membrane coated with GTA at 1 cc/min.
Both citric acid ethyl ester and GTA samples at 80 m/min and the 100 m/min samples (GTA) production rate show very little difference from the corresponding 60 m/min samples in flow surface structure, and no difference is apparent in either % BE, BF or permeability.
Using GTA as a coating for the poly(ethylene chlorotrifluoroethylene) fibres provides a remarkable amount of control over both the structure and porosity of the fibre surface. A lower coating flow rate still seems to keep the fibre permeable and enhances the asymmetry, whereas a higher coating flow rate gives a far more open surface. It is interesting is that the permeability of the 1 cc/min samples is not vastly different from the 5 cc/min samples, yet the fibre surface appears far less porous. This suggests that the internal pore size is very small. Thus if the surface porosity is controlled accurately then either the polymer concentration can be decreased or citric acid ethyl ester used as a solvent to increase the permeability, all while maintaining excellent bubble point/retention characteristic of the fibre.
Flat Sheet Preparation
Approximately 160 g of solvent (GTA or citric acid ethyl ester) was placed into a glass reaction vessel with a thermocouple to control the temperature. Stirring continuously, the solvent was heated to 230° C. before approximately 40 g of HALAR® 901LC fluoropolymer was added to the vessel. The polymer dissolved rapidly and was allowed to mix for 10-15 minutes before a sample of polymer solution was poured from the flask and onto a glass plate preheated to 120° C. The dope was then rapidly spread across the plate with a glass bar also preheated to 120° C. The bar had adhesive tape wound around the ends to raise it a uniform height above the plate when drawing the dope down, thus a sheet of uniform thickness was obtained. The cast membrane rapidly cooled and solidified to form a flat membrane sheet, which was washed in ethanol and dried in air.
Virus Retention Results
A sample of fluoropolymer hollow fibre membranes were prepared in accordance with the methods disclosed herein. The sample was prepared from a dope containing HALAR® 901LC fluoropolymer at a concentration of 21%, with a coating flow of 0.3 ml/min. The coating, the solvent and the lumen were all GTA. The quench was in water at 15° C.
Three to four fibres approximately 10 cm long were made into a loop and the cut ends sealed in epoxy glue. 148 kd Molecular weight. Dextran was filtered through this potted fibre. The feed and filtrate concentration was measured using HPLC and the percentage dextran retained by the fibre was calculated. Approximately 25% of the dextran was retained.
Virus Retention
In a similar fashion, three to four fibres approximately 10 cm long were made into a loop and the cut ends sealed in epoxy glue. A solution of MS2 type virus, at a feed concentration of approximately 30000 units per ml was filtered through this potted fibre. The log retention of virus was calculated and determined to be 4.30. Typically, a membrane having a viral log reduction of value of greater than 4 is considered to be an ultrafiltration membrane.
Permeability Test
The permeability of the fibres from the same batch as used for the dextran and virus retention tests was also determined. Three to four looped and potted 10 cm fibres were tested for permeability on a “porometer”. The porometer allows water to be filtered at 100 kPa pressure from the outside of the fibres to the inside and out through the fibre ends. The time required to pass 10 ml of water is recorded and used to calculate the permeability in litres/meter 2 hour, which in the present case was determined to be 300 litres/meter 2 hour.
The dextran, virus and permeability test were reproduced on a second batch of poly(ethylene chlorotrifluoroethylene) hollow fiber membranes prepared under identical conditions and identical results were obtained, suggesting that there were no reproducibility problems in the use of poly(ethylene chlorotrifluoroethylene) to make ultrafiltration and microfiltration membranes.
Poly(ethylene chlorotrifluoroethylene) on its own forms a particularly good membrane with an excellent bubble point and clean water permeability combined. The addition of coatings and silica adds another dimension to the membrane properties.
While the invention has been described with reference to particular embodiments, it will be understood by those skilled in the art that the inventive concept disclosed herein is not limited only to those specific embodiments disclosed. | Porous polymeric membranes including HALAR® (poly(ethylene chlorotrifluoroethylene)) and related compounds and the methods of production thereof which avoid the use of toxic solvents. Preferred solvents, coating agents and pore forming agents are citric acid ethyl ester or glycerol triacetate. The membranes may be in the form of a hollow fiber or flat sheet, and may include other agents to modify the properties of the membranes, such as the hydrophilic/hydrophilic balance. Leachable agents may also be incorporated into the membranes. | 8 |
BACKGROUND OF INVENTION
The present invention relates to an improved foot spraying and scrubbing device that is designed to conveniently and safely clean difficult areas of the foot such as between the toes. This invention has been designed in order provide a simple and fast means of cleaning feet in order to reduce the prevalence of commonly transmitted diseases such as fungal and bacterial infections that often occur in private bathrooms between family members and also in public places like gym lockers, showers and swimming pools. The present invention is a simple device for the general purpose of scrubbing feet, especially in regions between the toes. Due to its simplicity it is very amendable as a cost effective apparatus that can be purchased by any household or public facility.
In the prior art, foot cleaning devices have been disclosed. U.S. Pat. No. 4,918,779 claims a device that consists of a foot-controlled spray with brushes. In this device, the spray and brush comes from a horizontal position where the spray flows through the brush. U.S. Pat. No. 6,584,636 discloses a device that contains both vertical and horizontal brushes and wash feet using a stream of water coming from a source beneath the foot, which like the U.S. Pat. No. 4,918,779 patent, uses a steam of fluid that flows through the brush. Further the U.S. Pat. No. 6,584,636 patent is designed to wash shoes outdoors.
As opposed to the '636 patent, the present claimed invention is designed to wash feet in private or public bathrooms, gymnasiums or swimming pools. Further as opposed to the U.S. Pat. No. 6,584,636 patent, the stream of fluid can be a detergent that flows from a source that is from above the foot. The present invention also has attached removable scrubbing cords and callous sheets that are used to scrub the feet and are separated from the fluid source.
Using a fluid source that pours detergent from a position that is above the foot and is separated from the brushing mechanisms enables a more sanitary washing device. This is due to limited direct contact of feet to the position where the detergent is poured. This feature makes the present invention very suitable for public locations having large numbers of people where the frequency of contagious foot disease is high.
SUMMARY OF INVENTION
The present invention relates to an improved foot cleaning device that can both apply fluid and scrub the feet. The present invention can be used in private bathrooms or public areas such as sports arenas and swimming pools. The present invention includes the following interrelated components and aspects:
(a) In a first aspect, the present invention consists of a base, a front portion and a rear portion. The front portion is connected with the rear portion at the top of the present invention by forming an angle sufficient to form a stable structure. The present invention is stabilized using a bar that is positioned at the base of the device that attaches the front portion to the rear portion. (b) The base has a top surface and a bottom surface. The top surface will have ridges or a similar rough surface so that a person will not slip when washing the feet. The bottom surface will have suction cups used to fix the device to distinct positions on the bathroom floor such as the surface of the shower or bath tub. In the case of public facilities the device can be fixed to a define location by means of bolting the device down by securing bolts through the base. The recommended use of the invention is to use within reach of a handle such as one attached to a bathroom wall. (c) An embodiment of the present invention is to wash the bottom, front and back of the feet as well as the regions between the toes. Removable rough surface sheets are attached to the rear position of the present invention; the sheets are used to scrub the bottom and sides of the feet. Scrubbing cords are positioned in the front position of the present invention. The cords are used to scrub the top, sides and regions between the toes of the feet. The cords are removable so that they can be replaced when they become worn out. The cords will also be available in three sizes: men, women and children. (d) The fluid pours onto the scrubbing cords and the removable rough surface sheets from a fluid container tube that is positioned above the scrubbing cords. The fluid container pivots to form an angle sufficient to pour detergent either on the scrubbing cords or the rough surface sheets. The fluid container tube also rotates in either a clockwise or counterclockwise motion in order to pour detergent onto either the scrubbing cords or rough surface sheets. (e) The fluid is a detergent and is distributed into the container tube using an input nozzle that is positioned within the fluid container tube.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows the frontal view of the front of the present invention.
FIG. 2 shows the frontal view of the rear of the present invention.
FIG. 3 shows the side view of the present invention.
FIG. 4 shows an exploded view of the top part of FIG. 1 . FIG. 4A shows the perspective view of the present invention when liquid is not added to the scrubbing cords. FIG. 4B shows the perspective view when liquid is added to the scrubbing cords.
DETAILED DESCRIPTION
FIGS. 1–3 by reference describe a first embodiment of the present invention. The invention consists of a container tube 1 positioned above a top horizontal support linkage 2 , a front support linkage 3 and a back support linkage 4 . The linkages 2 , 3 , 4 can be one continuous tube or a plurality of connecting tubes. Illustrated in FIG. 3 , the structure is stabilized using a bar 27 that connects the front support linkage 3 to the back support linkage 4 . A preferred embodiment is to have the bar 27 be connected to the middle of the front and back support linkages 3 , 4 .
The container tube 1 is connected to the horizontal support linkage 2 by means of pivot connectors 5 . The pivot connectors 5 have an attached circular top end 21 and an attached circular bottom end 22 . The attached circular bottom end 22 is housed into bottom grooves 24 that enables the container tube 1 to pivot. The attached circular bottom end 22 has attached pins 25 to enable the container tube to move to fixed positions in the bottom grooves 24 that either enables fluid to pour over scrubbing cords 13 (illustrated in FIG. 1 ) or rough surface sheets 19 (illustrated in FIG. 2 ). The attached circular top ends 21 are housed in top grooves 28 in order to allow rotational movement of the container tube 1 . The attached circular top end 21 and the groove 28 are connected to the container tube 1 at a position of approximately ½ radius distance above the center of the container tube 1 in order to cause the container tube to rotate to a position where fluid is not poured onto either the scrubbing cords 13 or rough surface sheets 19 when force is released.
A preferred embodiment is that the top groove 28 is in an open position enabling the container tube 1 to be easily removed so that the user can refill the tube with detergent. This embodiment would be used for a private location. Another preferred embodiment is that the top groove 28 is in a closed position that locks the container tube 1 so that the container tube 1 cannot be removed. Situations like this would require the lock to be opened by an operator who has a key that causes the top groove 28 to be put into an opened position. This embodiment would be especially useful in public locations.
The support linkages 3 , 4 are connected to the top horizontal support linkage 2 by means of front legs 6 and rear legs 7 . The front legs 6 are connected to the front support linkage 3 by means of front bottom connectors 8 . The rear legs 7 are connected to the back support linkage 4 by means of rear bottom connectors 9 . The legs are connected to the top horizontal support linkage 2 by using top connectors 10 to make an angle that is sufficient to form a stable structure such as a 45 degree angle (illustrated in FIG. 3 ). The device is positioned above a base 11 . The base 11 is rigid having a surface connection means underneath. For private locations, the connection means are rubber suction cups. For public locations, the connection means are screws or any device that causes permanent attachment.
With reference to FIG. 1 , fluid is administered into the container tube 1 by means of a manifold nozzle 12 . The nozzle 12 is connected to the container tube 1 and can contain a removable cap. The fluid passes from the container tube 1 onto scrubbing cords 13 out of outlet orifices 14 that are positioned along the side of the container tube 1 . A preferred embodiment is that there are overhangs at the bottom end of the outlet orifices 14 to guide the pouring of fluid onto the scrubbing cords 13 . The scrubbing cords 13 are connected to the top horizontal support linkage 2 and the bottom front horizontal support linkage 3 so that they are easily removable so that they can be replaced. The container tube 1 is positioned above the top horizontal support linkage 2 in a sufficient angle to cause detergent to be poured on top of the scrubbing cords 13 .
The scrubbing cords 13 can be composed of porous or fibrous material to enable the absorption of liquid such as cloth or plastic. The cords 13 can also be elastic. A preferred embodiment is that the cords 13 are composed of double waved fibrous nylon. Another preferred embodiment is that the scrubbing cords 13 are removable so that they can be replaced when they are worn out. Another preferred embodiment is that the scrubbing cords 13 can vary in size in order to accommodate different sizes of feet.
The scrubbing cords 13 have structured ends 26 that can attach to the top horizontal support linkage 2 and the bottom horizontal support linkage 3 . Preferably the structured ends 26 of the scrubbing cords have a slender tubular shaft with a flat head having a larger diameter than the tubular shaft. This type of structure can securely fasten to irregular shaped holes 20 positioned along the linkages 2 , 3 where one part of the hole 20 is large enough for the flat head to enter into whereas the other part of the hole 20 is small enough to retain the flat head once the structured end 26 is directed into the smaller part of the hole 20 . This will securely attach the scrubbing cords 13 into horizontal linkages 2 , 3 . On the top horizontal support linkage 2 the irregular shaped holes 20 are aligned evenly across the linkage 2 . On the bottom horizontal support linkage 3 the irregular shaped holes 20 are aligned whereby the holes 20 towards the ends of the present invention are positioned lower down the side of the bottom horizontal support linkage 3 while the holes residing closer to the center of the present invention are increasingly positioned higher along the side of the bottom horizontal support linkage 3 . This enables the spaces between the toes to be comfortably scrubbed simultaneously.
FIG. 4 illustrates describes a portion of the container tube 1 , horizontal support linkage 2 and nozzle 12 and the mechanism for depositing the fluid onto the scrubbing cords 13 in detail. Downward rotational force is applied by the operator onto the container tube 1 that causes the container tube 1 to rotate downward whereby fluid is poured through the outlet orifices 14 onto the scrubbing cords 13 . A preferred embodiment is that the bottom parts of orifices 14 have overhangs 29 that guide the pouring fluid onto the scrubbing regions. In FIG. 4A , the overhangs 29 are displayed in a horizontal position and FIG. 4B illustrates the overhangs 29 being in a vertical position as they are used to guide the pouring of fluid onto the scrubbing cords 13 . When the downward force is released the container tube 1 rotates back to its original position whereby the remaining fluid is retained in the container tube 1 . This is done by gravity force due to the top groove 28 illustrated in FIG. 3 being approximately one half radius distance from the center of the container tube 1 end.
In FIG. 2 , a support sheet 15 is fixed in parallel with the rear legs 7 using vertical braces 16 and a horizontal brace 17 that connects the support sheet 15 to the top horizontal support linkage 2 and the bottom rear support linkage 4 . The support sheet 15 contains a plurality of orifices 18 in order to permit the passage of fluid and air. The support sheet 15 can be composed of plastic or rubber. Connected to the support sheet 15 are two rough surface sheets 19 that contain a coarse surface in order to enable the object to be cleaned such as a foot to be scrubbed. The rough surface sheets 19 can be connected to the support sheet 15 using any suitable adhesive such as glue. The rough surface sheets 19 can be removable. The rough surface sheets 19 are sufficient to remove callous” on feet. The container tube 1 can be pivoted into a position above the rough surface sheets whereby upon downward rotation of the container tube 1 detergent is poured out of orifices 23 onto the rough surface sheets 19 . A preferred embodiment is that there are overhangs at the bottom end of the outlet orifices 23 to guide the pouring of fluid onto the rough surface sheets 19 . | Disclosed is an improved sanitary foot washing device that is designed for washing feet in both private and public locations. This device has been created for the purposes of reducing the occurrences of foot mediated transmutable diseases that are prevalent in public locations like public showers and swimming pools. The device consists of a support having a system that administers fluid like detergents to scrubbing cords that enable the cleaning of all areas of the foot specially the regions between the toes. The support also has scrubbing sheets that enable the cleaning of the regions under feet as well as the regions on the sides of feet. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Ser. No. 14/298,389 filed on Jun. 6, 2014, which claims the benefit of U.S. Provisional Ser. No. 61/866,379, filed Aug.15, 2013, which are herein incorporated by reference.
BACKGROUND
[0002] 1. Field
[0003] Embodiments of the present disclosure generally relate to a wafer support cylinder used in a thermal process chamber.
[0004] 2. Description of the Related Art
[0005] In many semiconductor device manufacturing processes, the required high levels of device performance, yield, and process repeatability can only be achieved if the temperature of the substrate (e.g., a semiconductor wafer) is tightly monitored and controlled during processing of the substrate. Rapid thermal processing (RTP), for example, is used for several different fabrication processes, including rapid thermal annealing (RTA), rapid thermal cleaning (RTC), rapid thermal chemical vapor deposition (RTCVD), rapid thermal oxidation (RTO), and rapid thermal nitridation (RTN).
[0006] In a RTP chamber, for example, the substrate may be supported on its periphery by an edge of a substrate support ring that extends inwardly from the chamber wall and surrounds a periphery of the substrate. The substrate support ring is rested on a rotatable tubular support cylinder which rotates the substrate support ring and the supported substrate to maximize substrate temperature uniformity during processing. The support cylinder is made of opaque quartz to provide light shielding properties and low thermal conductivity such that heat from the processing area and/or the heating source is substantially attenuated near the support cylinder. The support cylinder is typically coated with a polysilicon layer to render it opaque to radiation in the frequency range used for temperature measurements of the substrate.
[0007] However, it has been observed that mismatch in thermal expansion coefficients of polysilicon layer and opaque quartz under high temperatures can cause cracking in the polysilicon layer and/or in the vicinity of the interface between the polysilicon layer and the opaque quartz. Such cracking can be detrimental to the substrate because the cracks may propagate into the underlying quartz which makes the polysilicon layer and a portion of the underlying quartz adhered to the polysilicon layer to peel after thermal cycling. The peeling of the polysilicon layer and the quartz pieces not only compromises opacity of the support cylinder but also contaminates the process chamber and the substrate with particles.
[0008] Therefore, there is a need for an improved support cylinder with enhanced light shielding properties that prevents contamination of the process chamber and the substrate during thermal processing.
SUMMARY OF THE INVENTION
[0009] Embodiments of the present disclosure generally relate to a support cylinder used in a thermal process chamber. In one embodiment, a support cylinder for a processing chamber is provided. The support cylinder includes a hollow cylindrical body comprising an inner peripheral surface, an outer peripheral surface parallel to the inner peripheral surface, wherein the inner peripheral surface and the outer peripheral surface extend along a direction parallel to a longitudinal axis of the support cylinder, and a lateral portion extending radially from the outer peripheral surface to the inner peripheral surface, wherein the lateral portion comprises a first end having a first beveled portion, a first rounded portion, and a first planar portion connecting the first beveled portion and the first rounded portion, and a second end opposing the first end, the second end having a second beveled portion, a second rounded portion, and a second planar portion connecting the second beveled portion and the second rounded portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.
[0011] FIG. 1 schematically illustrates a cross-sectional view of a rapid thermal processing chamber.
[0012] FIG. 2A is a schematic top view of a support cylinder that may be used in place of the support cylinder of FIG. 1 according to one embodiment of the disclosure.
[0013] FIG. 2B is a sectional view of the support cylinder taking along the line 2 B- 2 B of FIG. 2A .
[0014] FIG. 2C is an enlarged view of a portion “ 2 C” of the support cylinder shown in FIG. 2B .
[0015] FIG. 3 depicts a schematic side view of a portion of the support cylinder shown in FIG. 2B according to one embodiment of the disclosure.
[0016] FIG. 4 depicts a schematic side view of a portion of the support cylinder shown in FIG. 3 using a reflective coating layer according to another embodiment of the disclosure.
[0017] FIG. 5 depicts a schematic side view of a portion of the support cylinder shown in FIG. 3 according to yet another embodiment of the disclosure.
DETAILED DESCRIPTION
[0018] Embodiments of the present disclosure generally relate to a support cylinder used in a thermal process chamber. The substrate to be thermally processed is supported on its periphery by a support ring. The support ring extends radially inwardly along the inner circumferential surfaces of the process chamber and surrounds a periphery of the substrate. The support ring has an edge lip extending radially inwardly from a surface of the support ring to support the periphery of the substrate from the back side. The support ring has a bottom coupling to a support cylinder. The support cylinder comprises a ring body having an inner peripheral surface and an outer peripheral surface. The outer peripheral surface is further away from a central longitudinal axis of the support cylinder than the inner peripheral surface. The support cylinder may be made of a synthetic black quartz material which is opaque to infrared radiation. In one embodiment, the support cylinder is coated with a clear fused quartz which has high emissivity in the far infrared region. As the clear fused quartz and the underlying synthetic black quartz are all quartz components having similar coefficient of thermal expansion, the inventive support cylinder does not have particle contamination issues due to coefficient of thermal expansion mismatch between an opaque quartz and a polysilicon layer coated thereon, as would normally be seen in the conventional support cylinder. Various embodiments of the support cylinder are discussed in further detail below.
[0019] Exemplary Rapid Thermal Processing Chamber
[0020] FIG. 1 schematically depicts a cross-sectional view of a rapid thermal processing chamber 10 . Examples of a suitable RTP chamber may include RADIANCE® RTP or CENTURA® RTP chamber, available from Applied Materials, Inc., Santa Clara, Calif. While the processing chamber 10 shows a top heating configuration (i.e., heating lamps provided relatively above the substrate), it is contemplated that a bottom heating configuration (i.e., heating lamps provided relatively below the substrate) may also be utilized to benefit from the present disclosure. A substrate 12 , for example, a semiconductor substrate such as a silicon substrate, to be thermally processed is passed through the valve or access port 13 into the process area 18 of the processing chamber 10 . The substrate 12 is supported on its periphery by an annular support ring 14 . An edge lip 15 extends inward of the annular support ring 14 and contacts a portion of the backside of the substrate 12 . The substrate may be oriented such that processed features 16 already formed in a front surface of the substrate 12 face upwardly toward a process area 18 defined on its upper side by a transparent quartz window 20 . The front surface of the substrate 12 is facing toward the array of lamps 26 . In some embodiments, the front surface of the substrate 12 with the processed featured formed thereon may face away from the array of lamps 26 , i.e., facing towards the pyrometers 40 . Contrary to the schematic illustration, the features 16 for the most part do not project substantial distances beyond the front surface of the substrate 12 but constitute patterning within and near the plane of the front surface.
[0021] A plurality of lift pins 22 , such as three lift pins, may be raised and lowered to support the back side of the substrate 12 when the substrate is handed between a paddle or robot blade (not shown) bringing the substrate into the processing chamber and onto the support ring 14 . A radiant heating apparatus 24 is positioned above the window 20 and configured to direct radiant energy toward the substrate 12 through the window 20 . In the processing chamber 10 , the radiant heating apparatus may include a large number, 409 being an exemplary number, of high-intensity tungsten-halogen lamps 26 positioned in respective reflective tubes 27 arranged in a hexagonal close-packed array above the window 20 . The array of lamps 26 is sometimes referred to as the lamphead. However, it is contemplated that other radiant heating apparatus may be substituted. Generally, these involve resistive heating to quickly ramp up the temperature of the radiant source. Examples of suitable lamps include mercury vapor lamps having an envelope of glass or silica surrounding a filament and flash lamps which comprise an envelope of glass or silica surrounding a gas such as xenon, which provides a heat source when the gas is energized. As used herein, the term lamp is intended to cover lamps including an envelope that surrounds a heat source. The “heat source” of a lamp refers to a material or element that can increase the temperature of the substrate, for example, a filament or gas that can be energized, or a solid region of a material that emits radiation such as a LED or solid state lasers and laser diodes.
[0022] As used herein, rapid thermal processing or RTP refers to an apparatus or a process capable of uniformly heating a substrate at rates of about 50° C./second and higher, for example, at rates of about 100° C./second to 150° C./second, and about 200° C./second to 400° C./second. Typical ramp-down (cooling) rates in RTP chambers are in the range of about 80° C./second to 150° C./second. Some processes performed in RTP chambers require variations in temperature across the substrate of less than a few degrees Celsius. Thus, an RTP chamber must include a lamp or other suitable heating system and heating system control capable of heating at rate of up to about 100° C./second to 150° C./second, and about 200° C./second to 400° C./second, distinguishing rapid thermal processing chambers from other types of thermal chambers that do not have a heating system and heating control system capable of rapidly heating at these rates. An RTP chamber with such a heating control system may anneal a sample in less than 5 seconds, for example, less than 1 second, and in some embodiments, milliseconds.
[0023] It is important to control the temperature across the substrate 12 to a closely defined temperature uniform across the substrate 12 . One passive means of improving the uniformity may include a reflector 28 disposed beneath the substrate 12 . The reflector 28 extends parallel to and over an area greater than the substrate 12 . The reflector 28 efficiently reflects heat radiation emitted from the substrate 12 back toward the substrate 12 to enhance the apparent emissivity of the substrate 12 . The spacing between the substrate 12 and the reflector 28 may be between about 3mm to 9 mm, and the aspect ratio of the width to the thickness of the cavity is advantageously greater than 20 . The top of reflector 28 , which may be made of aluminum and has a highly reflective surface coating or multi-layer dielectric interference mirror, and the back side of the substrate 12 form a reflecting cavity for enhancing the effective emissivity of the substrate, thereby improving the accuracy of temperature measurement. In certain embodiments, the reflector 28 may have a more irregular surface or have a black or other colored surface to more closely resemble a black-body wall. The reflector 28 may be deposited on a second wall 53 , which is a water-cooled base made of metal to heat sink excess radiation from the substrate, especially during cool down. Accordingly, the process area of the processing chamber 10 has at least two substantially parallel walls, of which a first is a window 20 , made of a material being transparent to radiation such as quartz, and the second wall 53 which is substantially parallel to the first wall and made of metal significantly not transparent.
[0024] One way of improving the uniformity includes supporting the support ring 14 on a rotatable support cylinder 30 that is disposed radially inward of the inner circumferential surfaces 60 of the processing chamber 10 . The support cylinder 30 is magnetically coupled to a rotatable flange 32 positioned outside the processing chamber 10 . A motor (not shown) rotates the flange 32 and hence rotates the substrate about its center 34 , which is also the centerline of the generally symmetric chamber. Alternatively, the bottom of the support cylinder 30 may be magnetically levitated cylinder held in place by magnets disposed in the rotatable flange and rotated by rotating magnetic field in the rotatable flange 32 from coils in the rotable flange 32 .
[0025] Another way of improving the uniformity divides the lamps 26 into zones arranged generally ring-like about the central axis 34 . Control circuitry varies the voltage delivered to the lamps 26 in the different zones to thereby tailor the radial distribution of radiant energy. Dynamic control of the zoned heating is affected by, one or a plurality of pyrometers 40 coupled through one or more optical light pipes 42 positioned to face the back side of the substrate 12 through apertures in the reflector 28 to measure the temperature across a radius of the rotating substrate 12 . The light pipes 42 may be formed of various structures including sapphire, metal, and silica fiber. A computerized controller 44 receives the outputs of the pyrometers 40 and accordingly controls the voltages supplied to the different rings of lamps 26 to thereby dynamically control the radiant heating intensity and pattern during the processing. Pyrometers generally measure light intensity in a narrow wavelength bandwidth of, for example, 40 nm in a range between about 700 to 1000 nm. The controller 44 or other instrumentation converts the light intensity to a temperature through the well-known Planck distribution of the spectral distribution of light intensity radiating from a black-body held at that temperature. Pyrometry, however, is affected by the emissivity of the portion of the substrate 12 being scanned. Emissivity ε can vary between 1 for a black body to 0 for a perfect reflector and thus is an inverse measure of the reflectivity R=1−ε of the substrate back side. While the back surface of a substrate is typically uniform so that uniform emissivity is expected, the backside composition may vary depending upon prior processing. The pyrometry can be improved by further including a emissometer to optically probe the substrate to measure the emissivity or reflectance of the portion of the substrate it is facing in the relevant wavelength range and the control algorithm within the controller 44 to include the measured emissivity.
[0026] Exemplary Support Cylinder
[0027] FIG. 2A is a schematic top view of a support cylinder 200 that may be used in place of the support cylinder 30 of FIG. 1 according to one embodiment of the disclosure. The support cylinder 200 illustrated in FIG. 2A may be disposed within a processing chamber, for example a rapid thermal processing chamber 10 shown in FIG. 1 . The support cylinder 200 is generally a continuous ring body with a substantially consistent radial width “W”. The support cylinder 200 has an inner peripheral surface 202 and an outer peripheral surface 204 parallel to the inner peripheral surface 202 . The outer peripheral surface 204 is further away from a central longitudinal axis “C” of the support cylinder 200 than the inner peripheral surface 202 . While not shown, the support cylinder 200 is sized such that the outer peripheral surface 204 is disposed radially inward of the inner circumferential surfaces of the processing chamber, as discussed above with respect to FIG. 1 .
[0028] FIG. 2B is a sectional view of the support cylinder 200 taking along the line 2 B- 2 B of FIG. 2A . FIG. 2C is an enlarged view of a portion “ 2 C” of the support cylinder 200 shown in FIG. 2B . For a 300 mm substrate, the support cylinder 200 may have an outer diameter “D 1 ” (measuring from the outer peripheral surface 204 ) of about 310 mm to about 360 mm, for example about 330 mm, and an inner diameter “D 2 ” (measuring from the inner peripheral surface 202 ) of about 305 mm to about 350 mm, for example about 324 mm. The support cylinder 200 may have a thickness “T 1 ” ( FIG. 2B ) of about 10 mm to about 80 mm, for example about 24 mm. The support cylinder 200 may have a radial width (W 1 ) of about 2.5 mm to about 35 mm, for example about 6 mm. In general, the dimension of the radial width (W) is selected to ensure that the support ring (i.e., the support ring 14 of FIG. 1 ) to be placed thereon does not slip off the support cylinder 200 when the support cylinder 200 and the support ring rotate during the process. It is contemplated that the foregoing dimensions may vary if a larger or smaller substrate and/or processing chamber are used.
[0029] In one embodiment shown in FIG. 2C , the first end 206 of the support cylinder 200 may have a beveled surface portion 208 and a rounded surface portion 210 . The rounded surface portion 210 may have a radius of about 0.25 mm to about 0.5 mm to reduce mechanical stress in the support cylinder 200 . The beveled surface portion 208 connects to the rounded surface portion 210 through a planar surface 212 which extends radially from the outer peripheral surface 204 to the inner peripheral surface 202 of the support cylinder 200 . The beveled surface portion 208 is sloped downwardly toward the inner peripheral surface 202 at an angle “α” of about 15° to about 40°, for example about 30°, with respect to the inner peripheral surface 202 . The planar surface 212 may have a width “W 2 ” of about 0.5 mm. The planar surface 212 is configured to be in physical contact with a support ring (not shown) that supports a semiconductor substrate. Therefore, the support cylinder 200 only contacts the support ring with the planar surface 212 to substantially reduce the contact area available for conductive transfer of heat between the support cylinder 200 and the support ring (and therefore the substrate).
[0030] Similarly, the second end 214 of the support cylinder 200 may have a beveled surface portion 216 and a rounded surface portion 218 . The beveled surface portion 216 connects to the rounded surface portion 218 through a planar surface 220 which extends radially from the outer peripheral surface 204 to the inner peripheral surface 202 of the support cylinder 200 . The beveled surface portion 216 is sloped downwardly toward the outer peripheral surface 204 at an angle “θ” of about 15° to about 40°, for example about 30°, with respect to the outer peripheral surface 204 . The planar surface 220 is configured to couple to a magnetic rotor (not shown), which is magnetically coupled to the rotatable flange 32 ( FIG. 1 ) to induce rotation of the magnetic rotor and hence of the support cylinder 200 , the support ring and the supported substrate about the central longitudinal axis “C” of the support cylinder 200 .
[0031] The beveled surface portions of the support cylinder 200 may be formed using a laser machining technique or any suitable technique. Instead of using the planar surface 212 to contact the support ring, the first end 206 of the support cylinder 200 may be configured to provide a bump or a projection having a limited contact area for conductive transfer of heat between the support cylinder 200 and the support ring to be placed thereon. The bump or projection may be any suitable shape such as rectangular, rhombus, square, hemispherical, hexagonal, or triangular protrusions. Hemispherical-shaped bumps or projections may be advantageous in terms of effective thermal mass reduction since hemispherical-shaped bumps or projections further reduce the surface contact area between the support cylinder 200 and the support ring (and therefore the substrate placed thereon) by turning the surface contact into a point contact. The shape and/or dimension of the planar surface 212 (or bumps/protrusions if used) may vary so long as the support ring is supported securely with minimized contact area between the substrate support and the support cylinder 200 .
[0032] In one embodiment, the support cylinder 200 is made of an opaque quartz glass material. The opaque quartz glass material may have microscopically small gas inclusions or voids in high concentrations to make the support cylinder 200 opaque to radiation in the frequency range of the pyrometer (e.g., pyrometers 40 of
[0033] FIG. 1 ) used for temperature measurements of the substrate. The term “opaque” used herein may refer to quartz glasses having an apparent density ranging from 1.7-2.2 g/cm 3 , an average bubble or gas inclusion diameter ranging from 10 to 100 μm, and a bubble or gas inclusion content of 6×10 5 to 9×10 8 bubbles/cm 3 . As the opaque quartz glass material is able to block out radiation from external sources that might disturb the temperature measurements, the accuracy of the temperature measurement of the substrate is improved. In addition, a support cylinder made of the opaque quartz glass material has higher thermal resistivity which cuts down the conduction of heat from the center of the support cylinder 200 to the surrounding components such as the support ring. The gas inclusions or voids in the opaque quartz glass material also scatter the light trapped in the quartz to avoid the support cylinder 200 becoming a heat sink. One exemplary opaque quartz glass material is synthetic black quartz (SBQ), available from Heraeus Quarzglas GmbH & Co. KG, Germany. Alternatively, the opaque quartz glass material may be made with microscopic solid particles ZrO 2 and HfO 2 in addition to, or other than those made from gas inclusions or voids of various shapes. The synthetic black quartz is thermally insulating, dimensionally stable at high temperatures, and inherently opaque to infrared radiation in the frequency range of the pyrometer (e.g., pyrometers 40 of FIG. 1 ) to avoid undesirable interference with the pyrometer signal from the substrate. Particularly, the synthetic black quartz material has low coefficient of thermal expansion (about 5.1×10 −7 /° C.) so that the support cylinder 200 and the coating layer to be formed thereon (will be discussed below) have a coefficient of thermal expansion that is substantially matched or similar to each other to reduce thermal expansion mismatch, which may cause thermal stress under high thermal loads. The synthetic black quartz material also has very low impurity level. The low impurity level as described herein refers to a highly pure black quartz where the total content of metal impurities such as Na, K, Li, Al, Fe, Cu, Mg, Ca, and Ti is below 5 wt ppm or less. Some of properties of the synthetic black quartz material are provided in Table 1.
[0000]
TABLE 1
Electric
Thermal
Thermal
Dielectric
resistance
diffusion
Heat
expansion
Bending
Young's
constant
(Ω · cm)
ratio
conductivity
(×10 −7 /° C.)
Density
strength
modulus
∈
at 500° C.
(×10 −4 m 2 /s)
(w/(m · k))
at 500° C.
(g/cm 3 )
(N/mm 2 )
(Gpa)
(at 500 MHz)
1.51*10 12
0.00816
1.31
5.1
2.204
163
73.0
3.87
[0034] In some embodiments, the synthetic black quartz may be made by adding a blackening element or compound to a material of quartz glass. Suitable compounds may include V, Mo, Nb, C, Si, iron oxides or tungsten. The amount of the blackening element added is not particularly limited, but is generally 0.1 to 10% by weight based on the weight of the quartz glass. In some embodiments, the synthetic black quartz may be made by thermal spraying quartz glass or black silica on a substrate such as quartz glass, metals or ceramics. The support cylinder with such a black quartz glass thermal sprayed film formed on a substrate have excellent far infrared radiation property as well as excellent light shielding property and heat shielding property. If desired, an opaque quartz glass thermal sprayed film may be further laminated on the black quartz glass thermal sprayed film. The black quartz glass thermal sprayed film laminated with such an opaque quartz glass thermal sprayed film scatters infrared rays and is impervious to visible rays, and therefore it is more effective for heat insulation property.
[0035] In some embodiments, the opaque quartz glass material may be obtained by heating and burning a quartz glass porous body under a vacuum, under an atmospheric pressure, or under a high pressure of 0.05 MPa or higher (e.g., 1000 MPa) at high temperatures such as between about 900° C. to about 2500° C.
[0036] Other variations of the support cylinder 200 using the synthetic black quartz material are also contemplated. For example, the support cylinder 200 may be a core body made of clear quartz, silicon carbide, silicon-impregnated silicon carbide or the like, with a coating layer made of the synthetic black quartz material as discussed above covering most exposed surface of the core body.
[0037] FIG. 3 depicts a schematic side view of a portion of the support cylinder 200 shown in FIG. 2B according to another embodiment of the disclosure. In this embodiment, the support cylinder 200 is further coated with an optical transparent layer, for example a clear fused quartz material 302 . The clear fused quartz material 302 may have a refractive index of about 1.5. The clear fused quartz material layer 302 may have a thickness “T 2 ” of about 30μm to about 200 μm, for example about 100 μm. The clear fused quartz material layer 302 may cover the most exposed surfaces of the support cylinder 200 except for the beveled surface portion 216 , the planar surface 220 and the rounded surface portion 218 , which are the locations to be coupled to a rotor or other components. Alternatively, the clear fused quartz material layer 302 may cover the entire surface of the support cylinder 200 . The clear fused quartz material layer 302 is selected as it has low coefficient of thermal expansion (about 5.5×10 −7 /° C.) in the relevant temperature range of about 300° C. to about 1450° C. The clear fused quartz material layer may have a purity of at least 99.9% by weight of SiO 2
[0038] Providing a clear fused quartz material layer on the support cylinder 200 that is also made of quartz material (i.e., synthetic black quartz) is advantageous because the clear fused quartz material layer 302 exhibit good adhesion to the underlying synthetic black quartz material. Most importantly, the clear fused quartz material layer 302 has a coefficient of thermal expansion that is substantially matched or similar to the underlying synthetic black quartz material, thereby reducing or even avoiding the thermal stress on the support cylinder that can otherwise lead to cracking in the coating and rapid part degradation that compromises opacity and particle issues. The clear fused quartz material layer 302 also improves the emissivity of the support cylinder 200 in the infrared range. By increasing the emissivity of the support cylinder 200 in the infrared range, the support cylinder 200 can be heated more quickly so that the support cylinder 200 does not act as a thermal load taking away heat from the support ring and become a heat sink that might disturb the temperature measurements of the substrate.
[0039] For rapid thermal processing chambers that adapt a bottom heating type configuration (i.e., the substrate is held with its back surface in opposition to a radiant heat source while its upper surface on which the features such as integrated circuits face away from the radiant heat source), the support cylinder may further have a reflective coating layer formed on or part of the clear fused quartz material layer to control the temperature distribution of the support cylinder 200 . FIG. 4 depicts a schematic side view of a portion of the support cylinder 200 shown in FIG. 3 using a reflective coating layer according to yet another embodiment of the disclosure. It has been observed that the support cylinder 200 may become too hot and deform upon direct exposure to the radiant heat source, which in turn may cause the support ring and hence the supported substrate to shift horizontally. Therefore, the substrate temperature uniformity is undesirably affected. To prevent the support cylinder 200 from getting too hot, a reflective coating layer 402 may be applied onto the clear fused quartz material layer 302 on the inner peripheral surface 202 facing the radiant heat source so that the heat radiation is reflected back to the heating lamps to help the support cylinder 200 maintain at a lower temperature during processing. The reflective coating layer 402 may cover about 20% to about 100% surface area of the inner peripheral surface 202 . In various examples, the reflective coating layer 402 may cover about 25%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, about 95% surface area of the inner peripheral surface 202 . In some cases, the reflective coating layer 402 may cover the entire surface of the support cylinder 402 to assist in heat dissipation from the support cylinder 200 . Such a reflective coating layer 402 may be uniform over the inner peripheral surface 202 of the support cylinder 200 as shown, or it may be non-uniformly applied to counteract the non-uniformity of the infrared radiation from the radiant heat source impinging on the support cylinder 200 . In either case, the reflective coating layer 402 may have a thickness “T 3 ” of about 20 μ m to about 150 μm, for example about 60 μm.
[0040] The materials selected to fabricate the reflective coating layer 402 may have a coefficient of thermal expansion that is substantially matched or similar to the intermediate clear fused quartz material layer 302 to reduce thermal expansion mismatch, which may otherwise cause thermal stress in the layer accompanied with cracking under high thermal loads. Exemplary materials that may be used for the reflective coating layer 402 may include fused silica, borosilicate glass, or the like.
[0041] Although exemplary embodiments of the present disclosure are shown and described, those of ordinary skill in the art may devise other embodiments which incorporate the present disclosure, and which are also within the scope of the present disclosure. For example, the reflective coating layer 402 may be replaced with a heat absorptive coating layer to assist in heat dissipation from the support cylinder 200 by absorbing heat radiation from the radiant heat source and/or one or more components in the processing chamber. The material of the heat absorptive coating layer may be selected to absorb thermal radiation at a wavelength of 1 micron to 4 micron, or other wavelengths of interest. Some possible materials may include polyurethane material, carbon black paint or a composition including graphite.
[0042] Alternatively, instead of using the reflective coating layer 402 , the intermediate clear fused quartz material layer 302 may be doped with atoms 502 ( FIG. 5 ) which absorb radiation from the radiant heat source and/or one or more components in the processing chamber. The atoms 502 may be evenly provided within the clear fused quartz material 302 at the inner peripheral surface 202 , or over the entire clear fused quartz material 302 as shown in FIG. 5 . The doping may result in a more uniform temperature profile of the support cylinder 200 , if the dopants are uniformly distributed over the inner peripheral surface 202 or the entire surface of the support cylinder 200 .
[0043] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | Embodiments of the disclosure generally relate to a support cylinder used in a thermal process chamber. In one embodiment, the support cylinder includes a hollow cylindrical body comprising an inner peripheral surface, an outer peripheral surface parallel to the inner peripheral surface, wherein the inner peripheral surface and the outer peripheral surface extend along a direction parallel to a longitudinal axis of the support cylinder, and a lateral portion extending radially from the outer peripheral surface to the inner peripheral surface, wherein the lateral portion comprises a first end having a first beveled portion, a first rounded portion, and a first planar portion connecting the first beveled portion and the first rounded portion, and a second end opposing the first end, the second end having a second beveled portion, a second rounded portion, and a second planar portion connecting the second beveled portion and the second rounded portion. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
The following related applications were filed concurrently with the instant application.
______________________________________ SerialTitle Inventors Number______________________________________Improved High-Dielectric-Constant Summerfelt, 08/283.881Material Electrodes Comprising Beratan,Thin Platinum Layers Kirlin, GnadeImproved Electrodes Comprising Summerfelt, 08/283,468,Conductive Perovskite-Seed Layers Beratanfor Perovskite DielectricsImproved High-Dielectric-Constant Summerfelt, 08/283,442,Material Electrodes Beratan, abandonedComprising Thin Ruthenium Kirlin,Dioxide Layers GnadeHigh-Dielectric-Constant Material Nishioka, 08/283,871Electrodes Comprising Park, now U.S. Pat.Sidewall Spacers Bhattacharya, No. 5,489,548 SummerfeltA Conductive Amorphous-Nitride Summerfelt 08/283,441Barrier Layer for High-Dielectric-Constant Material ElectrodesA Conductive Exotic-Nitride Summerfelt 08/283,873Barrier Layer for High-Dielectric- now U.S. Pat.Constant Material Electrodes No. 5,504,041A Conductive Noble-Metal- Summerfelt, 08/283,454Insulator-Alloy Barrier Layer for Nicolet,High-Dielectric-Constant Material Reid,Electrodes Kolawa______________________________________
The following previously filed applications are related to the instant application:
______________________________________ Docket/ SerialTitle Inventors Number______________________________________Improved Electrical Gnade, 08/009,521 nowConnections to Di- Summerfelt U.S. Pat. No. 5,348,894electric MaterialsImproved Electrical Gnade, 08/260,149,Connections to Di- Summerfelt abandonedelectric MaterialsLightly Donor Doped Summerfelt, 08/040,946,Electrodes for High- Beratan, abandonedDielectric-Constant GnadeMaterialsLightly Donor Doped Summerfelt, 08/276,191,Electrodes for High- Beratan, abandonedDielectric-Constant GnadeMaterialsImproved Electrode Summerfelt, 08/041,025 nowInterface for High- Beratan U.S. Pat. No. 5,471,364Dielectric-ConstantMaterials______________________________________
FIELD OF THE INVENTION
This invention generally relates to improving electrical connections to materials with high-dielectric-constants, such as in the construction of capacitors.
BACKGROUND OF THE INVENTION
Without limiting the scope of the invention, its background is described in connection with current methods of forming electrical connections to high-dielectric-constant materials, as an example.
The increasing density of integrated circuits (e.g. DRAMs) is increasing the need for materials with high-dielectric-constants to be used in electrical devices such as capacitors. Generally, capacitance is directly related to the surface area of the electrode in contact with the capacitor dielectric, but is not significantly affected by the electrode volume. The current method generally utilized to achieve higher capacitance per unit area is to increase the surface area/unit area by increasing the topography, such as in trench and stack capacitors using SiO 2 or SiO 2 /Si 3 N 4 as the dielectric. This approach becomes very difficult in terms of manufacturability for devices such as the 256 Mbit and 1 Gbit DRAMs.
An alternative approach is to use a high permittivity dielectric material. Many perovskite, ferroelectric, or high-dielectric-constant (hereafter abbreviated HDC) materials such as (Ba,Sr)TiO 3 (BST) usually have much larger capacitance densities than standard SiO 2 -Si 3 N 4 -SiO 2 capacitors. Various metals and metallic compounds, and typically noble metals such as Pt and conductive oxides such as RuO 2 , have been proposed as the electrodes for these HDC materials. To be useful in electronic devices, however, reliable electrical connections should generally be constructed which do not diminish the beneficial properties of these high-dielectric-constant materials.
SUMMARY OF THE INVENTION
As used herein, the term "high-dielectric-constant" means a dielectric constant greater than about 50 at device operating temperature. The deposition of an HDC material usually occurs at high temperature (generally greater than about 500° C.) in an oxygen containing atmosphere. Many electrode materials oxidize and become insulating or otherwise degrade in this type of environment. An initial electrode structure formed prior to the HDC material deposition should be stable both during and after this deposition, while subsequent electrode structures formed after this deposition need only be stable after this deposition.
As mentioned hereinabove, Pt has been suggested for the electrodes of an HDC material layer in standard thin-film (herein defined as generally less than 5 microns (urn)) applications. However, although Pt is unreactive with respect to the HDC material, it has been found that it is difficult to use Pt alone as an initial electrode. Pt generally allows oxygen to diffuse through it and hence typically allows neighboring materials to oxidize. In addition, Pt also does not normally stick very well to traditional dielectrics such as SiO 2 or Si 3 N 4 , and Pt can rapidly form a silicide at low temperatures. Thus a Ta or TiN layer has been suggested as an adhesion or buffer layer under the Pt electrode. However, during BST deposition or annealing, oxygen can possibly diffuse through the Pt and oxidize the adhesion layer and make the adhesion layer less conductive. This may be more of a problem on the sides of the adhesion layer than on the top horizontal surface, since the Pt will generally be thicker on the top, and a better diffusion barrier..
Conductive oxides such as RuO 2 have also been suggested for the electrodes of an HDC material layer in standard thin-film applications. Again, although RuO 2 is unreactive with respect to the HDC material, it too generally has difficulties. For example, the electrical properties of the structures formed using these oxides are usually inferior to those formed using e.g. Pt. Many thin-film applications require a small leakage-current-density in addition to a large capacitance per unit area. The leakage current is sensitive to many variables such as thickness, microstructure, electrodes, electrode geometry and composition. For example, the leakage current of lead zirconium titanate (PZT) using RuO 2 electrodes is several orders of magnitude larger than the leakage current of PZT using Pt electrodes. In particular, it appears that the leakage current is controlled by Schottky barriers, and that the smaller leakage current with Pt electrodes appears to be due to the larger work function.
As used herein, the term "unreactive", when used in reference to a material contacting an HDC material, means a material which provides a stable conductive interface to the HDC material during and after processing. Note that when a conductive oxide such as RuO 2 is used for the unreactive layer (or another part of the electrode), that layer can also contain unoxidized or partially oxidized Ru. For example, an unreactive layer of Ru which is chemically changed by becoming partially or fully oxidized during the HDC deposition process is still considered unreactive since it still provides a stable conductive interface to the HDC material.
Other structures which have been proposed for standard thin-film structures include alloys of Pt, Pd, Rh as the electrode and oxides made of Re, Os, Rh and Ir as a sticking layer on single crystal Si or poly-Si. A problem with these electrodes is that these oxides are usually not stable next to Si and that these metals typically rapidly form silicides at low temperatures (generally less than about 450° C.). If other associated problems can be avoided or minimized, this type of electrode structure should retain its conductivity even after the deposition of the HDC material if an appropriate adhesion (barrier) layer(s) is used between the conductive oxide and the Si substrate.
Thus many of the proposed lower electrode structures comprise the following generic layers: HDC material/unreactive (oxygen stable) layer/adhesion (barrier) layer/substrate. In these structures, the adhesion layer typically comprises a conductive material that will oxidize under HDC material deposition conditions to provide a conductive oxide. It has been discovered that expansion stress and crack formation in the HDC material can occur due to the oxidizing and consequent expanding of the adhesion layer during HDC material deposition.
Although this oxidation/expansion can generally occur at any surface of the adhesion layer, oxidation of the top of the adhesion layer is substantially impeded by the overlying unreactive layer, and oxidation of the bottom of the adhesion layer is substantially impeded by the material surrounding it (e.g. the substrate). Generally, an exposed sidewall would be the most likely surface of the adhesion layer to be oxidized. Since most materials proposed for the adhesion layer experience a volume change when oxidized, the adhesion layer sidewall generally expands and deforms the overlying unreactive layer and causes stress and cracking of the HDC material layer. These cracks can reach from the upper surface of the HDC material layer down to the lower electrode, with detrimental results. For example, if a conductive layer, such as an upper electrode for a capacitor, is deposited on the HDC layer, the capacitor can have substantial leakage or even be shorted between the two electrodes.
Generally, according to the present invention, the sidewall of the adhesion layer is pre-oxidized before deposition of the HDC material (but after deposition of an unreactive noble metal layer). An important aspect of the present invention is that the pre-oxidation of the sidewall generally causes a substantial amount of the potential sidewall expansion (and consequent noble metal layer deformation) to occur before deposition of the HDC material. Potential sidewall expansion is defined as the total amount of expansion that occurs through HDC deposition and annealing (with or without pre-oxidation).
According to the present invention, the sidewall of the adhesion layer is substantially oxidized before HDC deposition. In contrast to the present invention, superficial oxidation (e.g. forming a few monolayers of oxide) at various stages of fabrication of a ferroelectric capacitor has apparently been described in the prior art. See European Patent Application 557,937 A1, D. Patel et al., Ramtron International Corp., filed Feb. 23, 1993. The oxidation described by D. Patel et al. is superficial and is apparently in a different portion of the structure and for a different purpose, i.e., better adhesion to the bottom glass layer and to the top ferroelectric material, than the present invention. The adhesion layer sidewall of the present invention must generally be more than merely superficially oxidized, since a superficially oxidized adhesion layer would generally still undergo substantial oxidation and expansion during HDC deposition, to the detriment of the structure.
One embodiment of the present invention is a microelectronic structure comprising a supporting layer having a principal surface, and an adhesion layer overlying the principal surface of the supporting layer, wherein the adhesion layer comprises a top surface and an expanded, oxidized sidewall. The structure further comprises a noble metal layer overlying the top surface of the adhesion layer, wherein the noble metal layer comprises a deformed area overlying the oxidized sidewall, and a high-dielectric-constant material layer overlying the noble metal layer. The high-dielectric-constant material layer is substantially free of expansion stress cracks in proximity to the deformed area of the noble metal layer.
A method of forming an embodiment of the present invention comprises forming a supporting layer having a principal surface, forming an adhesion layer on the principal surface of the supporting layer, and forming a noble metal layer on a top surface of the adhesion layer, wherein the adhesion layer comprises a substantially unoxidized sidewall. The method further comprises oxidizing the unoxidized sidewall of the adhesion layer to form a pre-oxidized sidewall, and depositing a high-dielectric-constant material layer on the noble metal layer. The preoxidized sidewall minimizes further oxidation and expansion of the adhesion layer adjacent the pre-oxidized sidewall. Expansion stress and cracking of the high-dielectric-constant material layer is minimized during the step of depositing the high-dielectric-constant material layer.
These are apparently the first microelectronic structures wherein an electrode to an HDC material comprises an adhesion layer with a pre-oxidized sidewall which impedes the adhesion layer from undergoing substantial oxidation and expansion during HDC material deposition. These structures may also be used for multilayer capacitors and other thin-film devices such as pyroelectric devices (e.g. (uncooled) infrared detectors), non-volatile ferroelectric RAMs (using permanent polarization properties), thin-film piezoelectric and thin-film electro-optic devices.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as other features and advantages thereof, will be best understood by reference to the detailed description which follows, read in conjunction with the accompanying drawings, wherein:
FIGS. 1-4 are cross-sectional views showing the progressive steps in the fabrication of a high-dielectric constant material capacitor with an electrode comprising a non-conductive, pre-oxidized sidewall; and
FIGS. 5-8 are cross-sectional views showing the progressive steps in the fabrication of a high-dielectric constant material capacitor with an electrode comprising a conductive, pre-oxidized sidewall.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIGS. 1-4, -here is shown a method of forming an embodiment of the present invention, a lower electrode structure comprising a preoxidized sidewall. FIG. 1 illustrates an SiO 2 layer 32 overlying silicon semiconductor substrate 30. SiO 2 layer 32 may or may not be capped with a diffusion barrier such as TiO 2 or Si 3 N 4 . TiSi 2 /poly-Si plug 34 provides electrical connection through SiO 2 layer 32. A 100 nm TiN layer 36 has been reactively sputter deposited and patterned etched on the structure.
Various other standard processes can be used to form this portion structure, such as sputter depositing Ti on poly-Si followed by an N 2 rapid thermal anneal (700° C. for 30 seconds) or NH 3 furnace anneal (575° C. for 10 minutes). The TiN is then selectively removed chemically using peroxide to form the patterned TiN layer 36 shown. In an alternate method, a vapor HF clean of the underlying poly-Si is performed immediately prior to the deposition of TiN layer 36, without using TiSi 2 . It is beneficial that the structure not be exposed to a contaiminating environment, such as the atmosphere, between the HF clean and the adhesion layer deposition process steps, in order to ensure good adhesion between the poly-Si and the TiN layer.
A 100 nm Pt layer 38 is then DC sputter deposited in a 5 mTorr Ar atmosphere using a Pt target with the substrate temperature held at 325° C. Pt layer 38 can also be deposited using e-beam evaporation, chemical vapor deposition (CVD), or metal-organic CVD (MOCVD). The height of Pt layer 38 can vary depending on the desired capacitance density of the HDC material, the total desired capacitance, and the generation of the device. For example, future devices such as 1G DRAMs may generally require taller capacitors to provide more electrode surface area/unit area as compared to 256M DRAM devices, since 1G DRAMs will generally need to provide more capacitance/unit area (due to e.g. increased functionality and shrinking device features). After deposition of Pt layer 38, photoresist is deposited and patterned. Platinum layer 38 is then dry etched in a low-pressure, high-density plasma reactive ion etch (RIE) reactor to form the structure shown in FIG. 1.
The structure is then annealed in a diluted oxygen (5%O 2 in N 2 ) gas at 650° C. to form TiO 2 sidewall 40 as shown in FIG. 2. The substantial deformation of the structure, including Pt layer 38, occurs at this point, before deposition of the HDC material. Alternatively, ozone could be used for annealing. Alternatively, the structure could be annealed at a lower temperature (e.g. 600° C.), allowing Pt layer 38 more time to relax than if the oxidation is performed at full BST deposition temperature. Another benefit of this oxidation anneal process is that Pt layer 38 can rearrange to round any relatively sharp corners after being etching, since sharp corner can cause excess leakage current or even cracks.
Then BST layer 42 is formed on the electrode structure using metal organic chemical vapor deposition (MOCVD) at 650° C. in an O 2 /Ar (1/9) mixture gas at a pressure of 10 mTorr, resulting in the structure shown in FIG. 3. Substantial oxidation or expansion of the TiO 2 sidewalls does not occur during BST deposition, thus minimizing expansion stress and cracks in BST layer 42. The deposition may used ionic, photonic, electronic or plasma enhancement. BST layer 42 may also be formed by CVD, sputter or spin coat methods.
Upper Pt electrode 44 is them sputter deposited and dry etched to form the capacitor structure shown in FIG. 4. This structure, with both lower and upper electrodes, can again be annealed to improve the capacitor properties.
With reference to FIGS. 5-8, there is shown a method of forming an another embodiment of the present invention, a capacitor with a lower electrode comprising conductive, pre-oxidized sidewalls. The structure illustrated in FIG. 5 is similar to the structure of FIG. 1, except that ruthenium is deposited for adhesion layer 46, instead of TiN. Since Ru has a conductive oxide, the surface of ruthenium layer 46 is oxidized to form RuO 2 layer 48, before deposition of Pt layer 38. In this embodiment, current will still be able to flow between substrate 30 and Pt layer 38 even though the top surface of the adhesion layer has been oxidized.
The structure is then annealed in an oxygen containing atmosphere to form RuO 2 sidewall 50 as shown in FIG. 6. As with the previous embodiment, the substantial deformation of the structure, including Pt layer 38, occurs at this point, before deposition of the HDC material.
Then BST layer 42 is formed on the electrode structure using MOCVD as described hereinabove, resulting in the structure shown in FIG. 7. Again, substantial oxidation or expansion of the RuO 2 sidewalls does not occur during BST deposition, thus minimizing expansion stress and cracks in BST layer 42. Upper Pt electrode 44 is them sputter deposited and dry etched to form the capacitor structure shown in FIG. 8.
One potential advantage of this embodiment is that the conductive sidewall structure of FIG. 8 generally allows more electrode surface area to be in contact with the HDC material as compared to the non-conductive sidewall structure of FIG. 4.
Another potential advantage of this embodiment is that the top surface of Ru layer 46 is oxidized before the deposition of Pt layer 38, so further oxidation of the top surface of the Ru layer 46/RuO 2 layer 48 is minimized. The existing oxide limits the formation of irregular oxidized areas on the top surface of the adhesion layer due to diffusion of oxygen through Pt layer 38 (e.g. along grain boundaries), which can cause hillocking of Pt layer 38.
The sole Table, below, provides an overview of some embodiments and the drawings.
TABLE______________________________________ Preferred orDrawing Specific GenericElement Examples Term Other Alternate Examples______________________________________30 Silicon Substrate Other single component semiconductors (e.g. germanium, diamond) Compound semiconductors (e.g. GaAs, InP, Si/Ge, SiC) Ceramic substrates32 Silicon First level Other insulators dioxide insulator (e.g. silicon nitride) Doped insulators (e.g. BSG, PSG, BPSG) May be more than one layer (e.g. Si.sub.3 N.sub.4 barrier over SiO.sub.2) May or may not be used (i.e. first level insulator, sub- strate, another insulating layer or a combination there- of may be the supporting layer for the lower elec- trode) Combinations of the above materials34 TiSi.sub.2 / Conductive Other metal compounds poly-Si plug (e.g. nitrides: titanium ni- tride, zirconium nitride; silicides: tantalum silicide, tungsten silicide, molyb- denum silicide, nickel silicide; carbides: boron carbide, tantalum carbide; borides: titanium boride) Conductive metals (e.g. tungsten, tantalum, titanium, molybdenum) Single component semicon- ductors (e.g. single- or poly-crystalline silicon, germanium) Compound semiconductors (e.g. GaAs, InP, Si/Ge, SiC) Other silicides may be used in a composite structure (Ni silicide, Co silicide, tungsten silicide) May be multiple layers (e.g. TiN/TiSi.sub.x /poly-Si) Combinations of the above materials36 TiN Adhesion Other conductive metal layer compounds46 Ruthen- (e.g. oxides: ruthenium oxide, ium osmium oxide, rhodium oxide, iridium oxide, indium oxide, tin oxide) Conductive metals (different from specific material selec- ted for drawing element 38 below) (e.g. tungsten, tantalum, titanium, tin, ruthenium, indium, osmium, rhodium, iridium) Ternary (or greater) amor- phous nitrides (e.g. Ta--Si--N, Ti--Si--N, Ta--B--N, Ti--B--N) Exotic conductive nitrides (e.g. titanium aluminum ni- tride, Zr nitride, Hf nitride, Y nitride, Sc nitride, La ni- tride and other rare earth nitrides, N deficient Al ni- tride, doped Al nitride, Mg nitride, Ca nitride, Sr nitride, Ba nitride) Alloys of the above exotic conductive nitrides with common Si processing ma- terials such as TiN, GaN, Ni nitride, Co nitride, Ta nitride, W nitride (e.g. Ta--Al--N) Noble metal insulator alloys (e.g. Pd--Si--N, Pt--Si--N, Pd--Si--O, Pd--Si--O, Pd--B--(O,N), Pd--Al--N, Ru--Si--(O,N), Ir--Si--O, Re--Si--N, Rh--Al--O, Au--Si--N, Ag--Si--N) May be multiple layers (e.g. TiN/TiSi.sub.x, TiN/TiSi.sub.x / poly-Si) May be a layer having rela- tively better barrier proper- ties over a layer having rela- tively better adhesive pro- perties (e.g. Ru/TiN) Combinations of the above materials38 Platinum Noble metal Other oxidation resistant layer noble or platinum group metals (e.g. palladium, iridium, rhodium) Combinations of the above materials Layers of the above mater- ials40 TiO.sub.2 Pre-oxidized Oxides formed from mater- sidewall ials used for drawing ele- ments 36 and50 RuO.sub.2 46 above (e.g. tantalum oxide, titanium oxide, tin oxide, indium oxide, iridium oxide, ruthen- ium oxide) Combinations of the above materials42 Barium High- Other perovskite, pyroelec- strontium dielectric- tric, ferroelectric, or high-di- titanate constant electric-constant oxides (e.g. material (Ba,Sr,Ca,Pb)(Ti,Zr)O.sub.3, layer (Pb,La)(Zr,Ti)O.sub.3, bismuth titanate, potassium tantalate, lead scandium tantalate, lead niobate, potassium niobate, lead zinc niobate, lead mag- nesium niobate, tantalum pentoxide, yttrium oxide) Donor, acceptor, or donor and acceptor doped oxides listed above Combinations of the above materials Layers of the above mater- ials44 Platinum Upper Conductive metal com- electrode pounds (e.g. nitrides: titanium nitride, ruthenium nitride, tin nitride, zirconium nitride; oxides: ruthenium dioxide, tin oxide, titanium oxide, TiON, zinc oxide, doped zinc oxide, iridium oxide; silicides: titanium silicide, tantalum silicide, tungsten silicide, molyb- denum silicide, nickel silicide; carbides: tantalum carbide; borides: titanium boride) Other noble or platinum group metals (e.g. palladium, ruthenium, rhodium, gold, iridium, silver) Reactive metals (e.g. tungsten, tantalum, titanium, molybdenum) Other common semiconduc- tor electrodes (e.g. aluminum, doped Si or Ge) Combinations of the above materials May contain more than one layer48 RuO.sub.2 Conductive Other conductive oxides oxide layer (e.g. ruthenium oxide, osmium oxide, rhodium oxide, iridium oxide, tin oxide, indium oxide) Combinations of the above materials______________________________________
A few preferred embodiments have been described in detail hereinabove. It is to be understood that the scope of the invention also comprehends embodiments different from those described, yet within the scope of the claims. With reference to the structures described, electrical connections to such structures can be ohmic, rectifying, capacitive, direct or indirect, via intervening circuits or otherwise. Implementation is contemplated in discrete components or fully integrated circuits in silicon, germanium, gallium arsenide, or other electronic materials families. In general the preferred or specific examples are preferred over the other alternate examples. The scale of the figures is neither to absolute nor relative scale; some thicknesses have been exaggerated for clarity of explanation. Some components of the lower electrode may sometimes be referred to as being part of the electrode and may sometimes be referred to as being interior to, exterior to, inside of, outside of, on, under, etc. the electrode; the structures and methods of the present invention are substantially the same in either case.
The adhesion layer may comprise other materials than those listed in the table but which are generally less preferred than those materials in the table. For example, the adhesion layer may comprise other metal compounds such as ruthenium nitride, tin nitride, tungsten nitride, tantalum nitride, titanium oxide, TiON, titanium silicide, tantalum silicide, tungsten silicide, molybdenum silicide, nickel silicide, cobalt silicide, iron silicide, chromium silicide, boron carbide, tantalum carbide, titanium carbide, zirconium carbide, titanium boride or zirconium boride. Alternatively, the adhesion layer may comprise other conductive metals (different from the specific material selected for drawing element 38) such as cobalt, iron, chromium, palladium, rhenium, zirconium, hafnium or molybdenum. Alternatively, the adhesion layer may comprise single component semiconductors such as single- or poly-crystalline silicon or germanium, or compound semiconductors such as GaAs, InP, Si/Ge or SiC.
While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is therefore intended that the appended claims encompass any such modifications or embodiments. | An improved method of forming a capacitor electrode for a microelectronic structure such as a dynamic read only memory is disclosed which has a high dielectric constant (HDC) material as a capacitor dielectric. According to an embodiment of the present invention, the sidewall of the adhesion layer (e.g. TiN 36) in a lower electrode is pre-oxidized after deposition of an unreactive noble metal layer (e.g. Pt 38) but before deposition of an HDC material (e.g. BST 42). An important aspect of the present invention is that the pre-oxidation of the sidewall generally causes a substantial amount of the potential sidewall expansion (and consequent noble metal layer deformation) to occur before deposition of the HDC material. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority from U.S. Provisional Application Ser. No. 60/447,455, filed Feb. 14, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to wallets. More specifically, it is a wallet worn on the hand with pockets on the backside and palm areas of the hand, but does not limit the usefulness of the other areas of the hand.
[0004] 2. Description of the Related Art
[0005] Traditional wallets are bulky and subject to theft. Frequently, those engaging in physical activities forego carrying a wallet for these reasons. This exposes the individual to inconvenience and possible danger in the event of a medical emergency.
[0006] Many devices have been created to accommodate various items in pockets or storage compartments such as a wallet or glove; however, some of the methods of attachment may lead to the possibility of theft or loss of items. Related art, such as Moir, U.S. Pat. No. 6,079,049 issued Jun. 27, 2000; Lonon, U.S. Pat. No. 5,003,637 issued Apr. 2, 1991 and others, discloses gloves with pockets or pouches that are detachable. With this type of structure, the risk of loosing items is greatly increased when performing physical activities which require the usage of an individual's hands.
[0007] Other gloves have been created with pockets or pouches for carrying weights during physical activities. Related art such as Guthrie et al., U.S. Pat. No. 4,326,706 issued Apr. 27, 1982 and others pertain to weights being contained in a pocket with a snap fastening method. The weights move freely in the pocket or pouch of these gloves therefore increasing the risk of dislodging the snap fastening method thus leading to injury.
[0008] There are other gloves that have a pocket attachment to allow a drinking container to be carried on the hand; Dzierson, et al., U.S. Pat. No. Des. 284,806 issued Jul. 29, 1986 etc. This method of attachment may not secure the drinking device properly if the size or shape of the drinking device doesn't permit a tight enclosure.
[0009] Various wallets and gloves have been developed to carry items in or around the hand. The previous attempts at carrying items in a safe and secure manner have fallen short of constructive methods of carrying items in pockets, pouches and compartments during activities where the hands are needed to perform certain tasks.
[0010] The present invention is designed for the person that may need to carry items while being active, whether walking, jogging, camping, attending carnivals, touring vacation spots, or going to concerts etc. The hand wallet allows a person to carry items while leaving the fingers free for other purposes. This invention does not enclose the fingers, allowing the primary function of carrying, grasping and holding various items possible.
[0011] The limitations of the related art previously discussed are overcome by the present invention. With this invention's ability to expand and a fabric base that is flexible, a variety of items can be inserted and contained in or around the hand. The hand wallet provides a first pocket area on the back of the hand and a second pocket area on the palm of the hand. A variety of closing means known in the field enable the pockets to be sized, shaped, and arranged in a variety of configurations. In general, the design of the hand wallet follows function, with the location of the pockets, purpose of the items carried, nature of the activity and items used dictating the structural aspects as previously mentioned of said hand wallet. The top protective flap of the first pocket can be modified to support a device such as a light for activities that are performed where a light source is required.
[0012] It is therefore an object of the present invention to provide a wallet which can comfortably be worn on a user's hand.
[0013] It is another object of the present invention to provide a wallet which is lightweight.
[0014] It is another object of the present invention to provide a wallet which can be used during physical activities.
[0015] It is yet another object of the present invention to provide a wallet which allows for transporting a variety of items in a secure fashion.
[0016] It is yet a further object of the present invention to provide a wallet which can comfortably be worn on a user's hand which does not restrict movement or use of the hand.
[0017] Finally, it is an object of the present invention to accomplish the foregoing objectives in a simple and cost effective manner.
SUMMARY OF THE DISCLOSURE
[0018] A wallet is described which may be attached to a user's extremity and which includes one or more pockets for carrying desired items. The wallet includes a flexible base to which one or more pockets are mounted. Preferably, one pocket is mounted such that it will be located on the back of the user's hand when in use and a second pocket will be located on the palm side of the user's hand when in use. The base may be attached to the user by use of a zipper or by elongate straps which surround the user's extremity and connect to each other by means of hook and loop fastener or other appropriate fastening means. In a further preferred embodiment, one or both of the pockets may expand to allow the transport of larger items. This may be accomplished by incorporating expansion panels in the side of the pocket or by incorporating an elastic panel into the pocket. Each pocket may further include a means for closing the pocket such that contained items are retained within the pockets. Or, alternatively, the pocket may include a retaining means inside. If desired, a protective flap may be provided to cover the pocket. The protective flap preferably would include a means for securing the flap over the pocket. In an alternate embodiment, the wallet includes a single pocket which extends around its periphery. This pocket can be configured to accept a drinking bladder, including an opening for removing the liquid from the bladder by the user. The pocket can be configured to accept a weight or can be used as storage for desired items.
DESCRIPTION OF THE DRAWINGS
[0019] [0019]FIG. 1 shows a top view of the preferred embodiment of the present invention;
[0020] [0020]FIG. 2 a is a view of the internal structure of the preferred embodiment of the present invention;
[0021] [0021]FIG. 2 b is a cross sectional view of the preferred embodiment of the present invention taken across line IIb of FIG. 2 a ;
[0022] [0022]FIG. 3 is a side view of the preferred embodiment of the present invention;
[0023] [0023]FIG. 4 is a side view of the preferred embodiment of the present invention;
[0024] [0024]FIGS. 5 and 6 are view of the palm side of alternate embodiments of the present invention;
[0025] [0025]FIG. 7 shows a top view of an alternate embodiment of the present invention;
[0026] [0026]FIG. 8 shows a bottom view of the alternate embodiment of the present invention shown in FIG. 7;
[0027] [0027]FIG. 9 shows a top view of an alternate embodiment of the present invention;
[0028] [0028]FIG. 10 shows a bottom view of the alternate embodiment of the present invention shown in FIG. 9;
[0029] [0029]FIG. 11 shows a side view of the alternate embodiment of the present invention shown in FIG. 9;
[0030] [0030]FIG. 12 shows a bottom view of the alternate embodiment of the present invention shown in FIG. 9 with a drinking bladder installed;
[0031] [0031]FIG. 13 shows a bottom view of the alternate embodiment of the present invention shown in FIG. 9 in the open configuration showing installation of a drinking bladder;
[0032] [0032]FIG. 14 shows an embodiment of a drinking bladder which can be used in the alternate embodiment of the present invention as shown in FIGS. 9-13;
[0033] [0033]FIG. 15 shows an embodiment of a weight which can be used in the alternate embodiment of the present invention as shown in FIGS. 9-13 in place of the drinking bladder;
[0034] [0034]FIG. 16 shows a perspective view of an alternate embodiment of the present invention in the open configuration;
[0035] [0035]FIG. 17 shows a perspective view of the alternate embodiment of the present invention shown in FIG. 16 in the closed configuration;
[0036] [0036]FIG. 18 shows a bottom view of the alternate embodiment of the present invention shown in FIG. 16 with a drinking bladder installed;
[0037] [0037]FIG. 19 shows an embodiment of a drinking bladder which can be used in the alternate embodiment of the present invention as shown in FIGS. 16-18; and
[0038] [0038]FIG. 20 shows a perspective view of the embodiment of the present invention.
Element List
[0039] [0039] 20 hand wallet
[0040] [0040] 22 slotted pocket
[0041] [0041] 24 protective flap
[0042] [0042] 26 base
[0043] [0043] 28 zipper
[0044] [0044] 30 expandable side
[0045] [0045] 32 elastic strap
[0046] [0046] 34 pocket
[0047] [0047] 36 wrist strap
[0048] [0048] 38 hook and loop fastener
[0049] [0049] 40 pocket
[0050] [0050] 42 band of material
[0051] [0051] 46 palm section
[0052] [0052] 50 opening
[0053] [0053] 52 pocket
[0054] [0054] 56 spout
[0055] [0055] 58 bladder body
[0056] [0056] 60 drinking bladder
[0057] [0057] 62 weight
[0058] [0058] 64 absorbent cloth material
[0059] [0059] 66 pocket
[0060] [0060] 68 pocket
[0061] [0061] 70 hand wallet
[0062] [0062] 72 drinking bladder
[0063] [0063] 74 drinking bladder
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0064] The following detailed description is of the best presently contemplated modes of carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating general principles of embodiments of the invention.
[0065] In the preferred embodiment of the present invention, a hand wallet configured to carry items is described. Because coverage of the fingers is not a primary object, the base material need only cover the hand sufficiently so as to provide a secure mount for the features described herein. The hand wallet may be worn over a glove or might enclose the fingers if desired for certain conditions such as inclement weather. For other circumstances, the fingers may be exposed to improve manual dexterity, so long as the base is secure. Indeed, as shown in FIG. 1, the hand wallet may be comprised of a base 26 made from a strip of appropriate material, such as neoprene or leather, secured about the palm and back of a hand, without finger holes at all.
[0066] [0066]FIGS. 1-4 and 20 show the preferred embodiment of the present invention 20 . A first pocket area may be located on the back of the hand for placing a variety of items, such as money, credit cards, personal identification, business cards, pass cards, and vital medical information cards etc. For such items, the first pocket area may include one or more slotted pockets 22 adapted to hold such cards. This first pocket area may also include expandable sides 30 , that allow it to expand vertically to accommodate various items. This first pocket area also preferably includes a protective flap 24 which can be closed by a zipper 28 or other appropriate means. The first pocket area can be modified to support items like a lighting device or other small portable devices such as a whistle or an electronic device. Indeed, such items could be life saving if the need arises. For example, if a jogger experiences a heart attack or seizure, the hand wallet 20 could accommodate medication or life saving information. In addition to customary items carried in a wallet, such a first pocket might accommodate a lighting device, gaming and trading cards or other communication devices. As equipment is reduced in size, personnel working law enforcement, package delivery, inventory, etc. could use the pocket for task specific electronic equipment. In this case, the pocket would be sized to accommodate the electronic item.
[0067] The hand wallet 20 is preferably affixed to the hand using a wrist strap 36 (see FIGS. 5, 6, 10 , 12 , 13 and 20 ). The wrist strap may be connected using hook and loop fastener 38 or other appropriate fastening means.
[0068] As shown in FIGS. 5 and 6, a second pocket area may be located in the palm of the hand that can be used for items such as keys, mobile phone, money, identification cards, cosmetics, mp3 player, etc. The structure of the second pocket area is preferably designed for comfortable use in the intended activity. Inside the second pocket area can be an elastic strap 32 for securing items, such as keys, pepper spray, a small medicine bottle, etc. This can be useful if a person is walking and a dog or person tries to attack. The pepper spray, for example, would be located in the palm of the hand, ready for use without searching. Again, the second pocket area can be tailored for the desired use. For example, multiple pockets 34 and 40 may be provided. One or more of the pockets on the second pocket area may be closed by using hook and loop fastener 38 or other appropriate fastening means. The pockets 34 and 40 are preferably formed used an outer band of material 42 at the appropriate edges of the pockets 34 and 40 to secure the pockets 34 and 40 to the hand wallet 20 .
[0069] In addition, both pocket areas are adapted for their respective position on the hand. FIGS. 1, 2, 3 and 7 show details concerning an embodiment of the first pocket area located on the back of the hand. This permits a broad range of designs and generally a greater pocket capacity. A protective flap 24 may be used with an internal fastener or closing device, such as a zipper 28 or a strip of hook and loop fastener 38 . FIGS. 5, 6 and 8 show alternate embodiments of the second pocket area located in the palm of the hand. Typically, the second pocket area will be sized for comfort. If desired, the second pocket area is aligned to orient its contents within the pocket for comfortable gripping by the hand.
[0070] The elastic strap 32 shown inside a pocket 40 in the second pocket area may maintain an item such as pepper spray and/or keys in a secure, but ready to use location. This pocket is preferably capable of expanding to allow for larger items. Hook and loop fastener 38 or other appropriate fasteners may be used to secure items in the pocket interior.
[0071] In an alternate embodiment of the present invention shown in FIGS. 7 and 8, this hand wallet 20 may be constructed from an absorbent cloth material 64 such as terry cloth. Many activities can lead to perspiration; in strenuous activities or during hot periods, sweat may flow into the eyes. By constructing the hand wallet 20 from an absorbent cloth material 64 like terry cloth, the wearer can remove sweat from all portions of the face. This alternate embodiment preferably includes a pocket 66 on the back of the hand as well as a pocket 68 on the palm side of the hand.
[0072] The hand wallet 20 itself may be modified or adapted to a particular activity. For example, a compact version that is shorter in coverage of the hand (i.e., fits around the palm and back area of the hand) as shown in FIG. 5, may be appropriate for low impact leisure activity. An alternative version shown in FIGS. 6 and 9- 13 , (i.e., an active wear version), includes a larger palm section 46 that is compatible with high impact training and is capable of being configured with training accessories, such as a hand weight 62 (see FIG. 15) or an integrated drinking bladder 60 , 72 or 74 (see FIGS. 14 and 19) shown in FIGS. 12, 13 and 18 . In some cases, the activity may require partial or full finger coverage.
[0073] With larger coverage, an active wear version of the hand wallet 20 would enable a larger pocket area that could accommodate a hand weight 62 or drinking bladder 60 , 72 or 74 . Such a hand weight 62 could be specially designed to wrap around the hand. This hand weight 62 can be made out of neoprene or other appropriate materials. The hand weight 62 can be filled with materials commonly used in the weight training industry. The active wear version pocket 52 could also accommodate a drinking bladder 60 , 72 or 74 . Such a drinking bladder 60 , 72 and 74 would be tailored for the pocket 52 and enable drinking during activities to avoid dehydration. A secondary feature of the stored liquid is to act as a weight during exercise. The active wear version shown in FIGS. 9-13, is also useful for handling larger items like an infant's feeding bottle or drinking bladder 60 , 72 and 74 and does not in anyway limit the usefulness of this version or the previous version.
[0074] To enable use of a drinking bladder 60 , 72 or 74 , the hand wallet includes an opening 50 through which a spout 56 can extend. The spout 56 is preferably designed for easy use during physical activity but can be of any design which will transport liquid from within the drinking bladder 60 , 72 or 74 to the user. For ease of use, the drinking bladder 60 , 72 or 74 is preferably a separate item. As shown in FIGS. 9-13, the pocket 52 is opened using the zipper 28 . The pocket 52 is opened and the filled drinking bladder 60 , 72 or 74 is placed within the pocket 52 such that the spout 56 can extend through the opening 50 . The pocket 52 is then closed using the zipper 28 , allowing consumption of the liquid from the drinking bladder 60 , 72 or 74 .
[0075] As shown in detail in FIGS. 14 and 19, the drinking bladder 60 or 72 is designed to extend on either side of the hand wallet and along both the back and palm side of the hand. Alternatively, the drinking bladder 74 may extend along only one side of the hand. The latter configuration is preferred where the user wishes to use the remaining side for storage of items other than the drinking bladder 74 . In either configuration, the drinking bladder 60 , 72 or 74 consists of a body 58 and a spout 56 . The body 58 is made from a material which is impermeable to liquid and can withstand the intended use of the hand wallet, a flexible plastic is preferred. The spout 56 is preferably made from a durable material such as a hard plastic. The spout can be of any design commonly used for drinking receptacles but preferably includes a means for opening the spout 56 to obtain liquid and for closing the spout 56 such that liquid is retained with the drinking bladder 60 , 72 or 74 .
[0076] Another alternate embodiment is shown in FIGS. 16-19. The hand wallet 70 in this embodiment is designed to completely surround a storage area, weight or drinking bladder. FIG. 16 shows the hand wallet is its opened configuration while FIG. 17 shows the hand wallet 70 in the closed configuration. The hand wallet 70 includes a zipper closing 28 (other closing means can be utilized) which joins the ends of the hand wallet 70 forming a storage area inside. The embodiment shown in FIGS. 16-19 is designed to accept a drinking bladder 72 and includes openings 50 for a spout 56 . As shown in FIG. 18, the drinking bladder 72 fits within the hand wallet 70 such that the spout extends through the openings 50 to allow access to the liquid within the drinking bladder 72 . While this embodiment is shown being used with a drinking bladder 72 , it can also accept a weight or other items as desired.
[0077] While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. | The present invention relates to wallets. The Hand Wallet is a receptacle that has pockets for containing various accessories. In Particular, it relates to accessories that are specially configured to serve specific functions, such as a wallet for carrying items during activities. This wallet is designed to be worn around the hand with unique expandable pockets. These pockets are designed to carry items like personal identification information, vital medical information, keys, drinking devices etc. This Hand Wallet will benefit those greatly in daily activities while giving a since of comfort and security. | 0 |
FIELD OF THE INVENTION
The present invention relates to an automatic transmission, and more particularly, to an improved shift control method and system to decrease shift shock.
BACKGROUND OF THE INVENTION
Generally, an automatic transmission determines a target speed on the basis of a shift map using vehicle speed and throttle open angle as parameters, and performs hydraulic pressure duty control in order to operate specific engaging members within the transmission. Gear shifting is thus automatically performed.
However, if a significant number of shift signals are continuously generated, for example, due to frequent depressions of the accelerator pedal in a short time period, a new shift signal is generated before a shift according to a previous shift signal has been terminated. In this circumstance, shift operation according to the previous shift signal stops and a new shift operation according to the new shift signal is performed. Consequently, frequent changes of the target speed in the automatic transmission cause the hydraulic pressure to be incorrectly routed so that shift shock occurs.
SUMMARY OF THE INVENTION
In a preferred embodiment of the present invention, the shift control method includes generating a first shift signal for shifting to a target shift speed, detecting a shift signal generated within a predetermined period after the generation of the first shift signal, and determining if the number of shift signals generated is greater than or equal to a predetermined number, withholding synchronization according to the current shift signal, and determining if synchronization according to a previous shift signal has been terminated, if it is determined that the number of the shift signals generated is greater than or equal to the predetermined number, and performing synchronization according to the current shift signal after the synchronization according to the previous shift signal has been terminated.
In a preferred embodiment, the shift control method further comprises performing the synchronization according to the current shift signal if the number of shift signals generated is smaller than the predetermined number. It is also preferable that the predetermined number is three, and the predetermined period is determined based on a target speed determination history of the shift signals generated before the current shift signal.
In another preferred embodiment of the present invention, a shift control system for an automatic transmission comprises plural sensors and an appropriately programmed control unit. More specifically, a vehicle speed sensor detects vehicle speed and outputs a corresponding signal. A throttle position sensor detects the open angle of the throttle valve and outputs a corresponding signal. The transmission control unit determines a target speed on the basis of signals input from the vehicle speed sensor and the throttle position sensor, and generates a corresponding shift signal. Preferably, the transmission control unit is programmed with various instructions for shifting control. These instructions may include instructions for generating a first shift signal for shifting to a target shift speed, instructions for detecting a shift signal generated within a predetermined period from the generation of the first shift signal and determining if a number of shift signals generated is greater than or equal to a predetermined number, instructions for withholding synchronization according to the current shift signal and determining if synchronization according to a previous shift signal has been terminated if it is determined that the number of the shift signals generated is greater than or equal to the predetermined number, and instructions for performing synchronization according to the current shift signal after the synchronization according to the previous shift signal has been terminated.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention, and, together with the description, serve to explain the principles of the invention, where:
FIG. 1 is a block diagram of a shift control system according to the present invention;
FIG. 2 is a flow chart showing a shift control method according to the present invention; and
FIG. 3 shows a shift control pattern in the shift control method according the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
As shown in FIG. 1, the shift control system according to the present invention includes a vehicle speed sensor 10 , a throttle position sensor 20 , an engine speed sensor 30 , a transmission control unit 40 , a memory 50 , and an actuator 60 .
The vehicle speed sensor 10 calculates a current vehicle speed, for example by using the speed of a transfer driven gear in the automatic transmission, and outputs a corresponding electrical signal. The throttle position sensor 20 detects a change rate of the position of the throttle valve that works together with an accelerator pedal and outputs a corresponding electrical signal. The engine speed sensor 30 detects engine speed based on calculation of crankshaft speed, and also outputs a corresponding electrical signal. Memory 50 comprises a shift pattern map as known in the art, using a vehicle speed and a throttle opening as parameters.
The transmission control unit 40 generally comprises a computer or other appropriately programmed processor and related components for executing control according to the teachings of the present invention. The transmission control unit 40 determines a target speed from the shift pattern map of the memory 50 using the detected throttle open angle and the detected vehicle speed, and generates a corresponding shift signal for shifting to the determined target speed. However, if the number of shift signals generated within a predetermined time period is greater than or equal to a predetermined number, a shift according to the shift signal generated after the predetermined number is reached occurs only after the shift according to the previous speed shifting has been terminated. For example, if the predetermined number is three, a shift according to the third shift signal is performed only after the shift according to the second shift signal is terminated, and a shift according to a fourth shift signal is performed only after a shift according to a third shift signal is terminated.
The actuator 60 is operated according to the signal input from the transmission control unit 40 , and regulates the hydraulic pressure duty such that shift synchronization for the target speed is performed.
Referring to FIG. 2, shift control method according to a preferred embodiment of the present invention will be explained hereinafter.
The transmission control unit 40 determines if a speed change is demanded on the basis of the change rate of the throttle valve opening while a vehicle is running (S 101 and S 102 ). The determination of the need for a speed change in this step is conventionally based.
If the transmission control unit 40 determines that a speed change is needed, the transmission control unit 40 determines the target speed from the shift pattern map stored in the memory 50 . The transmission control unit 40 then generates a corresponding shift signal and transmits the shift signal to the actuator 60 in order to control the hydraulic pressure duty such that a gear shift to the target speed is performed. A timer or counter is also started at this point (S 103 ).
The transmission control unit 40 then determines whether a new shift signal for shifting to a new target speed is generated within a predetermined time period after starting the timer (S 104 ). If it is not, synchronization for the shift to the demanded target speed is maintained.
If it is determined that the new shift signal has been generated, the transmission control unit 40 determines if the number of shift signals generated is greater than or equal to a predetermined number (S 105 ). The predetermined number may be selected by a person skilled in the art for a particular vehicle.
If the new shift signal is generated after the predetermined period, the actuator 60 is operated by the shift signal such that a speed shift to the target speed is performed. On the other hand, if it is determined that the number of shift signals generated within the predetermined time period is greater than or equal to the predetermined number, the transmission control unit 40 withholds synchronization to the target speed of the new shift signal (S 106 ). The control unit then determines whether synchronization to the speed shift according to the previous shift signal has been terminated (S 107 ). For example, if the predetermined number is three and a third shift signal is generated within the predetermined time period, the transmission control unit 40 determines whether the synchronization for the speed shift according to the second shift signal is complete before the speed shift according to the third shift signal is performed.
After the synchronization for the speed shift according to the previous shift signal has been terminated, the transmission control unit 40 performs hydraulic pressure duty control in order to perform synchronization for the speed shift according to the new shift signal (S 108 ). Once again, if the predetermined number is three, the synchronization for the speed shift according to the third shift signal is performed only after synchronization for the speed shift according to the second shift signal has been terminated.
The predetermined period is preferably determined on the basis of the target speed determination history before the current shift signal. For an example, if a first shift signal is a 4-2 kickdown shift signal, a second shift signal is a 2-4 lift-foot-up shift signal, and a third shift signal is a 4-2 kickdown shift signal, the predetermined period is determined considering a time period for terminating the 4-2 and 2-4 shifts. In this case, the predetermined period can be set as 2-3 seconds. On the other hand, if a first shift signal is a 4-1 kickdown shift signal, a second shift signal is a 1-4 lift-foot-up shift signal, and a third shift signal is a 4-1 kickdown shift signal, the predetermined period is determined considering a time period for terminating the 4-1 and 1-4 shifts. In this case, the predetermined period can be set as 3-4 seconds, because the time period for terminating the 4-1 and 1-4 shifts is generally longer than that for terminating the 4-2 and 2-4 shifts.
As shown in FIG. 3, a current shift speed is maintained as ‘a’ while the throttle opening is A%, and a shift speed is changed from ‘a’ to ‘b’, if the throttle opening is changed from A% to B%. Then, if the throttle opening is changed from B% to C% because of the operation of the accelerator pedal, the target speed is determined as ‘c’ and hydraulic duty control for synchronization to the target shift speed ‘c’ is performed.
If the a target speed is changed from ‘c’ to ‘d’ because of the throttle opening change from C% to D% by releasing the accelerator pedal within a predetermined time period t 1 , synchronization for the speed shift to ‘d’ is performed only after synchronization for the speed shift to ‘c’ has been terminated as shown in the drawing.
As stated above, in the shift control method according to the present invention, if the number of shift signals generated is greater than or equal to the predetermined number within the predetermined period, synchronization for the speed shift according to the shift signal after the predetermined number is performed only after synchronization for the speed shift according to the previous shift signal has been performed, and thereby incorrect routing of the hydraulic pressure can be prevented so that shift shock can be decreased.
Although preferred embodiment of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concepts herein taught which may appear to those skilled in the present art will still fall within the sprit and scope of the present invention, as defined in the appended claims. | A shift control method and system is disclosed in which the number of shift signals generated within a predetermined time period after a first shift signal is determined and compared to a predetermined number. If the number is equal to or greater than the predetermined number then the shift according to a prior signal must be completed before the next shift is performed. The system includes a control unit and sensors for controlling the transmission according to the disclosed method. The system and method thus prevents or reduces shift shock by ensuring that hydraulic control is properly routed within the transmission. | 5 |
PRIORITY
[0001] This application claims priority to European Patent Application No. 11187123.2, filed 28 Oct. 2011, and all the benefits accruing therefrom under 35 U.S.C. §119, the contents of which in its entirety are herein incorporated by reference.
BACKGROUND
[0002] The present disclosure relates to data compression using data transformation, such as Lempel-Ziv transformation, and encoding. Furthermore, the present disclosure relates to methods for generating an encoding table for symbols obtained by data transformation.
[0003] Safeguarding important data is usually performed by a data backup. To keep a historical representation of the backups, the data is generally backed up on removable data storage items, such as tape cartridges or the like. Usually, data backed up onto a storage medium needs to be compressed to save backup time and storage medium capacity.
[0004] Data compression is applied in various fields of information technology. For example, data compression is often applied for permanently storing data on a tape drive or the like. There is one standard established that is defined for tape drives, the so-called Linear Tape Open (LTO) standard, which provides a hardware compression scheme consisting of a Lempel-Ziv front end and a variable-length encoder back end. The back end encoder generates variable-length code words that are substantially used to encode the length of the matched strings in the history buffer. The data transformation generates symbols which can be used to reconstruct the original data stream.
[0005] The Linear Tape Open standard refers to the ECMA-321 for streaming lossless data compression. According thereto, the back end encoder allows specific extension of a particular source symbol to be used as a control symbol. In particular, according to the ECMA-321 specification, the control symbol is incorporated into the compressed data scheme to provide a command or a marker for controlling the decompression of the encrypted data stream.
[0006] In the ECMA-321 specification, the control symbol may correspond to a scheme 1 symbol, which indicates that the following data symbols are encoded according to a compression scheme. The compression scheme provides literals which correspond to unmatched data bytes and copy pointers which are an addressing representation of a data byte sequence matching a data byte sequence in a history buffer.
[0007] Furthermore, the control symbol may represent a scheme 2 symbol, which indicates that the following data sequence does not contain encoded data. The latter scheme might be useful if the data stream to be compressed has a high entropy, such that an efficient transformation to a set of copy pointers cannot be performed, i.e., after transforming the data stream to be compressed the encoded data stream would be longer than the original data sequence.
[0008] The back end encoding is usually performed as a kind of entropy encoding, wherein control symbols are encoded by maximum-length code words. According to the ECMA-321 specification, the total length of control symbols including a leading literal flag is 13 bits.
[0009] As the history buffer size tends to become larger in order to increase the compression ratio, efficient encoding of matched data streams in the history buffer requires variable-length code words that are longer than the control symbols. However, to provide a downward compatibility there is a need to keep the same control symbols that have been used up to now in devices applying data compression according to the ECMA-321 specification. Therefore, there is a need for designing compression schemes that incorporate control symbols of a given length.
SUMMARY
[0010] In one embodiment, a method for compressing a data stream includes transforming, with a transformation front end block of a data compressor, a data stream into a transformed data stream of referencing symbols and other data elements, the referencing symbols representing a data sequence in the data stream which is identical to a data sequence in a reference data block and being pointers to the identical data sequence in the reference data block; and encoding, with an encoding end block of the data compressor, the referencing symbols by replacing them with codewords according to an encoding scheme; wherein the transformed stream includes at least one control symbol indicating a change between a portion of the transformed data stream containing a sequence of the other data elements and a portion of the transformed data stream containing a sequence of the codewords for the referencing symbols, wherein the location of the control symbol within the transformed data stream defines the end of the respective portion of the transformed data stream; and wherein the encoding scheme provides that at least one codeword associated to one of the referencing symbols is longer than a codeword representing the control symbol.
[0011] In another embodiment, a device for compressing a data stream, includes a transformation front end block configured to transform a data stream into a transformed data stream of referencing symbols and other data elements, the referencing symbols representing a data sequence in the data stream which is identical to a data sequence in a reference data block and being pointers to the identical data sequence in the reference data block; and an encoding back end block configured to encode the referencing symbols by replacing them with codewords according to an encoding scheme; wherein the transformed stream includes at least one control symbol indicating a change between a portion of the transformed data stream containing a sequence of the other data elements and a portion of the transformed data stream containing a sequence of the codewords replacing the referencing symbols, wherein the location of the at least one control symbol within the transformed data stream defines the end of the respective portion of the transformed data stream; and wherein the encoding back end block is configured such that the encoding scheme provides that at least one codeword associated to one of the referencing symbols is longer than the codeword associated to the control symbol.
[0012] In another embodiment, a method is disclosed for generating a representation of an encoding scheme for use in the compression of a data stream into a compressed data stream, wherein the encoding scheme associates codewords to each of one or more referencing symbols and to at least one control symbol, wherein each referencing symbol indicates a replaced data sequence in the compressed data stream and wherein the control symbols indicate a change between the referencing symbols and other data elements in the compressed data stream. The representation of the encoding scheme is generated by providing a set of the occurrence frequencies of each of the referencing symbols; adding a freely selected frequency to the set of the occurrence frequencies associated with the control symbol; forming the encoding scheme using a Huffman encoding algorithm, so that to each referencing symbol a codeword is associated according to its frequency of occurrence; and iteratively adapting the frequency of occurrence of the control symbol until the codeword associated to the control symbol has a desired length.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0013] Embodiments of the present disclosure are described in more detail in conjunction with the accompanying drawings, in which:
[0014] FIG. 1 shows a block diagram of a circuit for processing a data flow in LTO and enterprise tape drives;
[0015] FIG. 2 shows a block diagram of a device for compressing a data stream comprising a transformation front end block and an encoding back end block;
[0016] FIG. 3 shows a flow diagram for illustrating a method for generating an encoding scheme; and
[0017] FIG. 4 shows a histogram indicating the occurrence frequencies of referencing symbols in a Calgary Corpus.
DETAILED DESCRIPTION
[0018] LTO tape drives are well known in the art. The LTO hardware may be a peripheral equipment to be interfaced with a computer system. The hardware comprises a drive unit for receiving a tape cartridge to which data is archived or backed up or from which stored data is retrieved. Furthermore, control electronics are implemented in the tape drive to process the data stream that is provided by the computer system to be backed up and/or to process the data stream retrieved from the tape cartridge to be delivered to the computer system.
[0019] FIG. 1 shows a schematic diagram representing a data flow in a LTO tape drive. Data to be backed up is provided as a stream of data records DS (data stream) by the computer system and is supplied to a CRC recorder 11 which serves for performing a cyclic redundancy check of each record of the data stream. Thereafter, the data is provided to a data compressor 12 which applies a data compression on the data stream coming from the CRC recorder 11 , as will be explained later.
[0020] The compressed data stream is then delivered to a data encrypter 13 which employs an appropriate encryption, for example block encryption such as a Galois Counter Mode (GCM) encryption algorithm or the like. Subsequently, the encrypted data stream is supplied to an ECC (error correcting code) data encoder 14 which serves for adding error correction bits to data records of the data stream. The data stream is then split in n sub-streams in a splitter 15 , wherein the number of sub-streams corresponds to the number of simultaneously written tracks on the tape. The sub-streams are then randomized by means of randomizers 16 and RLL (run length-limited) encoded in RLL encoders 17 . RLL is a line coding technique for transmitting arbitrary data over a communication channel. RLL bounds the length of sequences of repeated bits during which the signal does not change due to a limited clock recovery. The data sub-streams thus processed are then provided to respective write heads 18 of the tape drive to simultaneously write the n tracks onto the tape in the tape cartridge.
[0021] For reading back data from the tape, the sub-streams are simultaneously read and the combined data stream is processed inversely to the data flow scheme for writing data onto the tape as described above.
[0022] The efficiency with respect to time and storage consumption is mainly affected by the efficiency of compression, i.e., the compression ratio. The compression ratio is the ratio of the length of the incoming data stream and the length of the compressed data stream.
[0023] According to the LTO specification, compressing the data stream shall conform to the standard ECMA-222 (June 1995), titled “Adaptive Lossless Data Compression Algorithm”, and the standard ECMA-321 (June 2001), titled “Streaming Lossless Data Compression Algorithm”. As illustrated in FIG. 2 , the compression algorithm described therein consists of two substantial steps which may be performed by means of a transformation front end block 21 , such as a Lempel-Ziv front end block, and an encoding back end block 22 , such as a variable-length code back end block.
[0024] The transformation front end block 21 substantially serves for replacing data sequences in the data stream with referencing symbols as possible. Referencing symbols are also referred to as copy pointers and are eventually represented as codewords in the compressed data stream. The data sequences are replaced when an identical match of the data sequence can be found in a preceding part of the data stream, which may be temporarily held in a history buffer. The referencing symbol has a format that indicates the position of the identical data sequence in the history buffer with respect to a current pointer marking the start of the matched data sequence. The referencing symbol further indicates the length of the matched data sequence and the byte following the matched data sequence. According to the Lempel-Ziv 77 standard referred to in ECMA-222, a symbol has a format of <d, l, s >, where “d” represents the displacement, “l” represents the length of the matched sequence and “s” represents the byte following the matched data sequence.
[0025] The transformation process performed in the transformation front end block 21 uses a history buffer of a predetermined size. The size of the history buffer used to be 1 kB, but will be increased to 16 kB in the near future. The history buffer stores a moving frame which follows a current pointer pointing to the first byte of the data sequence to be matched. The current pointer is moved forward/downstream every time a data sequence matching process has been completed. The maximum length of a data sequence a copy pointer can refer to is 271 bytes. After a matching data sequence of 271 bytes has been found, a copy pointer is generated and the sequence matching process is restarted beginning with the next byte.
[0026] In case the data sequence matching does reveal one or more matched data sequences with a low number of repeated bytes, the above format of triples provides an inefficiency caused by the fact that the obtained set of referencing symbols is represented by codewords that could actually be longer than the matched data sequences they were replacing. In the Lempel-Ziv-Storer-Szymanski compression scheme as referred to in ECMA-321, a replacement of a data sequence with a referencing symbol is omitted if a length of a codeword representation of the matched data sequence is less than a break even length, i. e. a minimum compressible length of a data sequence. To differentiate between referencing symbols and uncompressed bytes, the Lempel-Ziv-Storer-Szymanski compression uses one-bit leading literal flags for each symbol and each byte to indicate whether the next chunk of data is a literal, i.e., an uncompressed byte, or a reference symbol indicating an offset/length pair. The break even length corresponds to the length of the uncompressed bytes including the literal flags.
[0027] According to the ECMA-321 standard, all copy pointers are encoded by the literal “1”, which is a bit “1”, added as a leading bit to the codeword representation of the copy pointer, wherein a literal 0, which is a bit “0”, is added as a leading bit to the data byte, thereby indicating that the byte following the literal 0 represents an uncompressed byte.
[0028] In other words, with data byte sequences of short lengths, the above non-compressing encoding results in a 9-bit representation in the encoded data stream for every data byte. This might result in an encoded data stream that has 12.5% more bits than the original data stream. In order to reduce this data expansion, a new mode may be introduced which is, according to the ECMA-321 standard, called scheme 2 encoding, while the above-described generation of copy pointers is called scheme 1 encoding. The scheme 2 encoding provides that the data bytes are copied to the output bit stream without any leading literal flag bits.
[0029] In order for a decoder to distinguish a group of uncompressed/unencoded data bytes (according to scheme 2) from the representation of one or more control symbols, a control symbol is defined which corresponds to a predefined codeword. For random data this tends to produce an encoded data stream that has about 0.05% more bits than the original data stream. Hence, the control symbol indicates that the following data byte in the encoded stream represents a portion of the original sequence of data bytes of the data stream where the data bytes are not encoded.
[0030] To end the scheme 2 encoding and/or to switch to the scheme 1 encoding, another control symbol may be provided. According to the ECMA-222 standard, the symbols are encoded with a predetermined match count field which is a table that associates the symbols according to the length of the match. The table as defined by the ECMA-222 standard is illustrated in the following Table 1. It can be seen that the length of the bit code increases depending on the length of the matched byte sequence, while according to the probability of existing matched patterns a short bit code represents a short data byte sequence; with increasing length of the data byte sequence, the length of the bit code also increases.
[0000]
TABLE 1
Encoding table according to ECMA-321
Length of matched data sequence
Codeword representation
2
0 0
3
0 1
4
1 0 0 0
5
1 0 0 1
6
1 0 1 0
7
1 0 1 1
8
1 1 0 0 0 0
9
1 1 0 0 0 1
.
.
.
.
.
.
15
1 1 0 1 1 1
16
1 1 1 0 0 0 0 0
17
1 1 1 0 0 0 0 1
.
.
.
.
.
.
31
1 1 1 0 1 1 1 1
32
1 1 1 1 0 0 0 0 0 0 0 0 0
33
1 1 1 1 0 0 0 0 0 0 0 0 1
.
.
.
.
.
.
270
1 1 1 1 1 1 1 0 1 1 1 0
271
1 1 1 1 1 1 1 0 1 1 1 1
Control symbol
1 1 1 1 1 1 1 1 0 0 0 0-
1 1 1 1 1 1 1 1 1 1 1 1
[0031] According to the ECMA-321 standard, which focuses on the scheme switching between scheme 1 and scheme 2 as explained above, the control symbols are predefined and are encoded as fixed codewords having the same length as the codewords for encoding a data byte sequence of 271 bytes. According to the ECMA standard, the maximum length of the codewords is 12 plus a leading bit of the literal flag (literal “1”) indicating that the following codeword represent a copy pointer or a control symbol, respectively. The encoding table is designed such that the leading part of the codeword is unique, thereby clearly indicating the overall length of the respective codeword, such that no misinterpretation can occur and codewords can be safely discriminated.
[0032] Furthermore, for the sequence of uncompressed bytes according to scheme 2 encoding it has to be ensured that uncompressed data bytes cannot be misinterpreted as a control symbol and vice versa. As the codeword representation of the control symbol as shown above is set to consist of 13 “ones” in a row (literal 1 and 12 bit “1”), the representation of a data byte “1111 1111” in scheme 2 is “1111 1111 0”, i.e., every time a byte “1111 1111” occurs in the uncompressed data stream of scheme 2 a bit “0” is attached to avoid the accidentally occurrence of a bit sequence which could be interpreted as a control symbol. So it can be avoided to indicate the length of the (scheme 2) stream of uncompressed data bytes in advance. In general, this is achieved by defining codewords and the set of allowed uncompressed data bytes so that the bit sequence of the codeword representation of the control symbols is unique over the whole encoded data stream.
[0033] However, one drawback of the predetermined encoding table is the fact that although the codeword associated with the symbols up to a length of 270 bytes of a matched pattern according to their probabilities, a codeword representing a matched data byte sequence of 271 bytes and the codewords representing the control symbol both have a length of 12 bits although their probability of occurrence is higher than, e.g., the probability of occurrence of a codeword representing a matched data byte sequence of 270 bytes. The probability of a matched data byte sequence of a length of 271 bytes is higher than the probability of a data byte sequence of 270 bytes as according to the compression scheme the maximum length of matched data byte sequences is limited to 271 bytes, such that the probability of the occurrence of a data symbol representing a matched data byte sequence length of 271 bytes corresponds to the sum of probabilities of the occurrence of data byte sequences of lengths of 271 bytes and more.
[0034] To correct this mismatch, it may be provided that either the control symbol or the copy pointer for a matched data byte sequence of 271 bytes or both are represented by codewords with a reduced length, i.e., with a length shorter than the length of the codeword representing a matched data byte sequence of 270 bytes.
[0035] To better represent the probability of occurrence of data byte sequence lengths of 271 bytes and more, an encoding table is proposed as follows:
[0000]
TABLE 2
Encoding table with reduced codeword size for control
symbols and matched data sequence lengths of 271 bytes
Length of matched data sequence
Codeword representation
2 bytes-3 bytes
0 <1 bit> (2 bits)
4 bytes-5 bytes
1 0 <1 bit> (3 bits)
6 bytes-7 bytes
1 1 0 <1 bit> (4 bits)
8 bytes-9 bytes
1 1 1 0 <1 bit> (5 bits)
10 bytes-11 bytes
1 1 1 1 0 0 <1 bit> (7 bits)
12 bytes-15 bytes
1 1 1 1 0 1 <2 bit> (8 bits)
16 bytes-23 bytes
1 1 1 1 1 0 <3 bit> (9 bits)
271 bytes
1 1 1 1 1 1 0 1 0 1 (10 bits)
24 bytes-31 bytes
1 1 1 1 1 1 0 0 <3 bit> (11 bits)
Control Symbols
1 1 1 1 1 1 1 1 0 0 0 0-
1 1 1 1 1 1 1 1 1 1 1 1 (12 bits)
32 bytes-47 bytes
1 1 1 1 1 1 1 0 0 <4 bit> (13 bits)
48 bytes-79 bytes
1 1 1 1 1 1 1 0 1 <5 bit> (14 bits)
80 bytes-143 bytes
1 1 1 1 1 1 0 1 1 <6 bit> (15 bits)
144 bytes-270 bytes
1 1 1 1 1 1 0 1 0 0 <7 bit> (17 bits)
[0036] Therein, the codeword lengths increase with the sequence length of matched data byte sequences to be represented thereby, except for the codeword representation for data byte sequences of 271 bytes or more. Data byte sequences of 271 bytes or more are represented by a 10-bits codeword while data byte sequences of lengths of 144 bytes to 270 bytes are represented by a 17-bits codeword.
[0037] Although the codeword length of the longest defined codeword is longer than proposed by the ECMA standard, namely 17 bits compared to 12 bits (without literal flag), the average codeword length for a given sample data source is shorter. For a sample data source corresponding to a Calgary Corpus (a collection of 14 text and binary data files used for comparing data compression algorithms), the average codeword length is 3,437220 bits. The average code length when using the encoding table according to the ECMA standard corresponds to 3.636128 bits. It can be seen that the average code word length may be significantly reduced by more than 1% indicating that the compression was performed more efficiently.
[0038] Furthermore, depending on the kind of data to be compressed, the encoding table may be generated by preserving control symbols of a predetermined size and predetermined bit pattern. As the control symbols are predefined in the LTO specification, they must not be redefined since existing backed up data could not be decompressed or decoded, respectively.
[0039] The encoding table may be optimized for a given data source, such as the sample data source mentioned above, i.e., a Calgary Corpus. However, other kinds of data sources may also be used as a basis for generating an encoding table.
[0040] The flow diagram of FIG. 3 illustrates a method for generating an encoding table based on a given data source and based on the bit length of the codewords of one or more additional control symbols with a length of K bits.
[0041] As illustrated in FIG. 3 , in block S 1 an input histogram H 0 is provided or generated that represents the probabilities of data byte sequences in a given data sample.
[0042] In FIG. 4 , a histogram for the Calgary Corpus sample is shown. The histogram H 0 indicates the frequencies of N occurrences of matched data byte sequences of a given length from 2 to 271 bytes (N=270). It can be seen that the frequencies/probabilities decrease according to the grey approximation line (least-squares logarithmic tail fit), wherein the frequency of occurrence of a data byte sequence generally is the lower the longer the respective data byte sequence is. This is not true for the data byte sequence of a length of 271 bytes, the probability of which corresponds to the cumulated probabilities of occurrences of data byte sequences of lengths of 271 bytes or more.
[0043] In block S 2 , an iteration counter i is initially set to 1 and a variable d 1 is set to a first constant c 1 , which is a positive integer and determines the speed of convergence.
[0044] In block S 3 , the histogram H 0 is extended with the frequency of a further element d i (i=1, 2, 3, . . . ) to obtain a new (N+1) value histogram H i =[H 0 d i ]. As indicated in block S 4 , an (N+1) symbol code C i is constructed with symbol probabilities H i /sum (H i ) according to a Huffman coding algorithm. A Huffman coding algorithm is an entropy encoding algorithm used for lossless data compression. The Huffman code provides a variable-length code table for encoding a source symbol, wherein the variable-length code table has been derived in a particular way based on the estimated probability of occurrence for each possible value of the source symbol.
[0045] As is generally known in the art, the Huffman algorithm works by creating a binary tree of nodes. The algorithm essentially begins with the nodes containing the probabilities of the symbol they represent, wherein a node is created whose children are those two nodes with the lowest probabilities, such that the new node probability equals the sum of the children's probabilities. With the previous two nodes merged to one node and with a new node being now considered having a next higher probability, the procedure is repeated until only one node remains and until there is no next node having a higher probability.
[0046] According to the Huffman coding algorithm, the encoding table is obtained as a representation of the tree. To obtain the codeword representation of each element (length of a matched data sequence) represented by a respective end node of the tree and its associated probability, each branch of the tree is associated with a branch bit. The closer the branch is to one of the end nodes the higher is the significance of the respective bit. Appending all branch bits on the way from the end node to the root of the tree results in the codeword which represents the respective element of the end node.
[0047] In block S 5 , the length A of the thus obtained codeword representing the added element C i (N+1) is computed.
[0048] In block S 6 , the iteration is performed. If it is determined in decision block S 6 that the length A of the codeword representing the added element C i (N+1) corresponds to a desired length of the additional control symbol, which is given as K, then the encoding table of block S 4 may be used as the encoding table which is optimized for the given data source and the given length of the control symbols and the process ends.
[0049] If it is determined in decision block S 6 that the length A of the codeword representing the added element A=C i (N+1)>K, then the variable d i+1 is set to d i+1 =d i +c 2 in block S 7 . c 2 is a second constant that is predetermined and determines the speed of convergence.
[0050] In block S 9 , the counter i is incremented and it is continued with block S 3 . If it is determined in block S 6 that the length A of the codeword representing the added element C i (N+1)<K, then the variable d i is set to d i+1 =d i −c 2 in block S 8 and the method returns to block S 3 after the incrementation of the counter in block S 9 .
[0051] The extension of the histogram H 0 is performed again with the adapted element d i and the Huffman encoding table is generated again, such that an optimized encoding table may be obtained in an iterative manner. The first and second constants c 1 and c 2 should be judiciously selected. The careful selection of the constants finally determines the speed of convergence.
[0052] The above-described process of generating an encoding table is suitable to compute upper bounds on the compression of matched data sequence lengths in copy pointers using the information-theoretic measure entropy. This may be achieved by using the Huffman algorithm to obtain a Huffman encoding table for replacing the encoding table that is provided by the ECMA standard. The proposed encoding table has a 17-symbol variable-length code for matched data sequence lengths that preserves the control symbols specified in the LTO specification, such that an improvement of 1% or more in compression ratio can be achieved.
[0053] While the disclosure has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the disclosure not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this disclosure, but that the disclosure will include all embodiments falling within the scope of the appended claims. | A method for compressing a data stream includes transforming a data stream into a transformed data stream of referencing symbols and other data elements, the referencing symbols representing a data sequence identical to a data sequence in a reference data block; and encoding the referencing symbols by replacing them with codewords according to an encoding scheme, the transformed stream includes at least one control symbol indicating a change between a portion of the transformed data stream containing a sequence of the other data elements and a portion of the transformed data stream containing a sequence of the codewords for the referencing symbols, the location of the control symbol within the transformed data stream defines the end of the respective portion of the transformed data stream, the encoding scheme providing at least one codeword associated to one of the referencing symbols is longer than a codeword representing the control symbol. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to the use of micro fuel cells to power wireless computer pointing devices.
BACKGROUND OF THE INVENTION
[0002] Wireless optical navigation devices such as battery operated optical mice with radio frequency or infrared transmitters are presently available based on sensors such as Agilent Technology's ADNS-2030 or ADNS-2020. Typically, a light emitting diode (LED) light source illuminates the surface under the mouse as the mouse is moved. Battery life is limited by the system's total power consumption including the optical light source, such as the LED, the optical sensor, processing electronics and the radio frequency or infrared transmitter. Depending on the amount of use, typical intervals for battery changes for wireless, battery operated optical mice is in the range from 1 to 3 months. Additionally, batteries add considerable weight to the optical mouse interfering with ease of use.
SUMMARY OF THE INVENTION
[0003] In accordance with the invention, an attractive application for micro fuel cells is to provide a lightweight power source for wireless optical navigation devices such as wireless optical mice used as a pointing device in conjunction with computers such as personal computers and workstations. In particular, micro fuel cells offer an environmentally friendly source of power allowing six months or more of typical use for wireless optical navigation devices for computers before refueling is required.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 shows a micro fuel cell layout suitable for use with a wireless optical navigation device in accordance with the invention.
[0005] FIG. 2 a shows an embodiment in accordance with the invention.
[0006] FIG. 2 b is a simplified diagram showing the electrical connections in accordance with an embodiment of the invention.
[0007] FIG. 3 shows a micro fuel cell configuration in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0008] In accordance with an embodiment of the invention, FIG. 1 shows water recycling micro fuel cell system 100 suitable for integration with a wireless optical navigation device, such as a wireless optical mouse, to allow extended operation. Micro fuel cell system 100 includes fuel cell stack 120 , fuel source 140 coupled to anode side 160 of fuel stack 120 and oxidant source 185 coupled to cathode side 180 of fuel cell stack 120 . A water recovery mechanism 122 separates and collects water from the cathode exit stream and feeds water from cathode side 180 of fuel cell stack 120 to mixing chamber 124 where fuel is hydrated prior to delivery to anode side 160 of fuel cell stack 120 . Mixing chamber 124 includes water input port 126 and fuel input port 128 . Fuel recovery mechanism 129 recycles hydrated fuel from anode side 160 of fuel cell stack 120 and discharges anode gas products (e.g., carbon dioxide) into anode gas exit stream.
[0009] In micro-fuel cell system 100 , selectively permeable membrane 130 is positioned upstream of water input port 126 . Membrane 130 is permeable to water but largely impermeable to fuel. Hence, selectively permeable membrane 130 allows water to enter mixing chamber 124 while largely preventing outflow of fuel to cathode side 120 of fuel cell stack 120 . Selectively permeable membrane 130 inhibits fuel from mixing with oxidant at cathode side 180 of fuel cell stack 120 to prevent contamination of the oxidant and reduced cathode performance.
[0010] Selectively permeable membrane 132 is located upstream of fuel input port 128 . Selectively permeable membrane 132 is permeable to fuel and largely impermeable to water. Selectively permeable membrane 132 prevents the outflow of water from mixing chamber 124 into fuel source 140 . Thicknesses and cross-sectional areas of selectively permeable membranes 130 , 132 are selected to achieve a target mixing ratio of fuel and recycled water, typically in the range of about 0.5/99.5 to about 4/96. To achieve the desired flow rates of recycled water and fuel, some embodiments in accordance with the invention may include multiple channels to supply recovered water from cathode side 180 of fuel stack 120 into mixing chamber 124 and multiple channels to supply fuel from fuel source 140 into mixing chamber 124 .
[0011] Selectively permeable membrane 130 is permeable to water and largely impermeable to fuel. Exemplary materials for selectively permeable membrane 130 for a direct methanol micro fuel cell include hydrophilic material such as mordenite or perfluorosulfonic acid polymer such as NAFION® available from E. I. Du Pont de Nemours Company. Selectively permeable membrane 132 is permeable to fuel and largely impermeable to water. Exemplary materials for selectively permeable membrane 132 for a direct methanol micro fuel cell include hydrophobic material such as polyolefins and rubbery polymers such as neoprene.
[0012] For embodiments in accordance with the invention, fuel cell stack 120 may be implemented using any one of a wide variety of different fuel cell technologies such as low-temperature polymer electrolyte fuel cell technology. The micro fuel cell may use liquid or gas reactants. For liquid based micro fuel cells, the recycled water may serve as a dilutent. In these systems, osmosis through selectively permeable membrane 130 accomplishes the dilution. For feed gas based micro fuel cells, product water at cathode side 180 of fuel cell stack 120 may be used for humidification. In feed gas based systems, diffusion from wet cathode side 180 to dry feed gas provides water transport. In one embodiment in accordance with the invention, micro fuel cells in fuel cell stack 120 are implemented as direct methanol micro fuel cells which each include a membrane electrode assembly that is formed from a thin, proton transmissive solid polymer membrane-electrolyte or ion-exchange membrane positioned between an anode layer and a cathode layer. The membrane electrode assembly is typically sandwiched between a pair of electrically conductive anode and cathode current collectors and typically contains channels for distributing hydrated methanol from mixing chamber 124 over the anode and distributing air from oxidant source 185 over the cathode.
[0013] Water recovery mechanism 122 recovers water from cathode side 180 of fuel cell stack 120 and may be a passive water recovery mechanism such as a membrane selectively permeable to cathode gas products and impermeable to water. Fuel recovery mechanism 129 recovers hydrated fuel from anode side 160 of fuel cell stack 120 and may include a membrane that is selectively permeable to anode gas products and impermeable to the hydrated fuel received from anode side 160 of fuel cell stack 120 .
[0014] FIG. 2 a shows a simplified side view of the layout of major components for wireless optical mouse 200 in accordance with an embodiment of the invention using micro fuel cell system 100 described in FIG. 1 . Fuel cartridge 210 is positioned over mixing and osmotic membrane region 225 and air vents 230 . Typical dimensions for fuel cartridge 210 are determined by the need to store the desired amount of methanol fuel. Fuel cartridge 210 is typically replaceable and incorporates selectively permeable membrane 132 (see FIG. 1 ). It is typically convenient to have selectively permeable membrane 132 be part of the replaceable fuel cartridge as the membrane is degraded by contaminants during use leading to clogging.
[0015] Rechargeable battery 245 , such as a 20 g lithium polymer battery operating at 3 volt, provides about 3 W hours of power. Rechargeable battery 245 directly powers wireless optical mouse 200 and is recharged by fuel cell stack 270 from which power is preferentially drawn at a constant rate. Fuel cell output is limited by the exchange membrane ionic resistance, by the crossover time of the reactants across the ion exchange membrane positioned between cathode side 180 and anode side 160 of fuel cell stack 120 and mass transport of reactants to the electrodes. A narrow peak power operating window results. Therefore, a fuel cell is typically not good for applications requiring burst power. Rechargeable battery 245 is typically used in embodiments requiring high frame rates (see discussion below) as is the case for an optical mouse for videogame applications. Here it is important for wireless optical mouse 200 to respond to rapid movement. For lower frame rates, a capacitor (not shown) may be substituted for rechargeable battery 245 . For example, if wireless optical mouse 200 has a burst power requirement of 100 mW but burst power is required for only 10% of the operating time of wireless mouse 200 , typical for a low power optical mouse with relatively low frame rate, the use of a capacitor on the order of 1 μF allows fuel cell stack 120 to operate at a constant power outpt that is about 10% of the burst power requirement of 100 mW.
[0016] The air intake portion of air vents 230 typically includes two filters. A first filter is relatively coarse and used to keep particulate contaminants out of fuel cell stack 270 . A typical material for the first filter may be the porous foam used in personal computer cooling fan applications. A second filter is used to keep water from passing out of wireless optical mouse 200 while allowing air into fuel cell stack 270 ; filter materials such as GORTEX® may be used for the second filter. Fuel cell stack block 270 includes fuel recovery mechanism 129 and mixing chamber 124 . Typical dimensions for fuel cell stack 270 are about 5 cm 2 area with an approximate thickness on the order of 5 mm. The anode vent portion of air vents 230 is an exhaust to allow reaction by-products to exit fuel cell stack 270 . For an embodiment using a methanol fuel cell, the anode exhaust gas is carbon dioxide. Cathode vent portion of air vents 230 includes water recovery mechanism 122 and allows the venting of water vapor.
[0017] Printed circuit board block 240 may be an existing wireless optical mouse control board with area dimensions of about 5 cm by 8 cm. The optical navigation system includes optical source 290 which may be a low powered VCSEL (vertical cavity surface emitting laser) based optical mouse, an edge emitting low powered laser based optical mouse or an LED (light emitting diode) based optical mouse. Additionally the optical navigation system includes imager 285 , imaging lens 216 and lens 215 as well as the relevant navigation electronics in mouse control electronics 235 . An important feature for optical navigation systems is the frame rate, defined as the number of images obtained at the navigation surface per unit time. In an embodiment in accordance with the invention shown in FIG. 2 a, light from optical source 290 passes through lens 215 to a surface and returns to imager 285 via imaging lens 216 . Lens 215 functions to adjust collimation and beam size. Mouse control electronics 235 typically includes the radio frequency or infrared transmitter that allows wireless optical mouse 200 to communicate with a computing device having a video interface. Considerations for the optical system typically include the desire to have compact optics to reduce package size and reducing distances lowers the collimation requirements. Additionally, large diameter lenses are expensive and bulky. Compact design allows the use of most of the light by the imager while reducing the problem of stray light from divergent beams over larger distances. Typical choices for imager 285 are CMOS or CCD detectors in the range of 17 by 17 pixels to 33 by 33 pixels The use of compact optics also provides for more design freedom for the layout of fuel cell system 100 or similar systems.
[0018] FIG. 2 b is a simplified block diagram showing the electrical layout of an embodiment in accordance with the invention for optical wireless mouse 200 . Fuel cell stack is connected to battery 245 , so that anode 160 is electrically connected to the negative battery terminal 299 of battery 245 and cathode 180 is electrically connected to positive battery terminal 298 . Battery 245 is electrically connected in parallel to imager 285 , optical source 290 and control electronics 235 .
[0019] An important consideration for a wireless optical navigation device such as wireless optical mouse 200 is the operation time available between refueling. A reasonable interval between refueling which provides an advantage over conventional battery operated wireless optical mice is on the order of six months. To estimate the amount of fuel required for a typical six months of operation, a power budget must be obtained. A typical low power VCSEL source requires approximately 5 mW of power, a typical CMOS imager together with the processor requires approximately 30 mW and a radio frequency transmitter having the desired ranges requires about 20-40 mW (Bluetooth) yielding a total power requirement of 55-75 mW. Assuming an average use of six days per week, eight hours per day for six months gives 1152 hours of use. Assuming a user interaction time of about 10% during which time wireless optical mouse 200 operates at full power and otherwise is in sleep mode where there is no power draw results in about 115 hours of actual operation. Hence, the total power budget for six months of use is approximately 35 W hours. Assuming a micro fuel cell efficiency of between about 20-30% and using methanol, with a thermal energy of 5600 W hours/kg, results in the need for about 4-6 g of methanol to achieve the six month operation requirement. Power requirements may be further reduced if an infrared link is used in place of the radio frequency as power consumption is typically less than 5 mW. An infrared link typically requires a line of sight to the computer.
[0020] The operation time between refueling may be improved by higher efficiency fuel cells, use of fuels with higher thermal energies and system level power management improvements. System level improvements include using low power electronics, simplified navigation algorithms requiring less processor overhead, smaller CMOS imagers and use of pulsed LEDs or lasers.
[0021] FIG. 3 shows simplified a side view of fuel cell portion 300 of an embodiment in accordance with the invention. Fuel cartridge 345 is typically located above mixing chamber 310 and next to anode region 375 . Fuel cartridge 345 includes fuel membrane 350 which is typically part of fuel cartridge 345 . Mixing chamber 310 houses water membrane 312 and includes selectively permeable membrane 130 . A microelectromechanical system (MEMS) pump (not shown) may be used to facilitate mixing at about 0.05 cc/hour if diffusive mixing is inadequate. Typical MEMS pumps have power requirements much less than 1 mW. Insulation layer 320 located between fuel cartridge 345 and anode region 375 acts to thermally insulate fuel cartridge block 345 from anode region 375 . Anode region 375 includes anode side 160 of fuel stack 120 shown in FIG. 1 . Air vent 316 vents anode region 375 and air vent 315 vents cathode region 380 . Typically, two layers of filter material cover air vents 315 to prevent entry of contaminants-a first outer layer that is coarse to keep out particulates and a second layer underneath that is finer, made from material such as, for example, GORTEX®. Membrane 325 separates anode region 375 from cathode region 380 and contains the fuel cell membrane electrode assembly. Cathode region 380 includes cathode side 180 of fuel cell stack 120 shown in FIG. 1 . Cathode region 380 is adjacent to water recovery region 330 which includes an array of microchannels of water recovery mechanism 122 (see FIG. 1 ). The microchannels are typically about 1-5 mm in length with a width and depth of about 100 μm. The number of microchannels needed in water recovery region 330 is determined by the power output and the resulting flow rate. Given a micro fuel cell operating at about 20-30% efficiency, the methanol flow rate is about 0.04 cc/hour. Water production from a 1 W fuel cell is approximately on the order of magnitude of the perspiration of a human which is about 6.1×10 −4 g/hour and scales linearly with the power of the fuel cell.
[0022] While the invention has been described in conjunction with specific embodiments, it is evident to those skilled in the art that many alternatives, modifications, and variations will be apparent in light of the foregoing description.
[0023] Accordingly, the invention is intended to embrace all other such alternatives, modifications, and variations that fall within the spirit and scope of the appended claims. | A fuel cell is integrated with an optical navigation device to extend operational lifetime. A water recycling fuel cell is used to reduce fuel requirements to allow operation of a remote optical navigation device together with a computer on the order of six months or more. | 6 |
REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. application Ser. No. 10/568,489, filed Jun. 21, 2006 under 35 U.S.C. 371 as the national stage of PCT/GB2004/003525, filed Aug. 16, 2004, which application claims benefit of GB 0319255.6, filed Aug. 15, 2003.
BACKGROUND
[0002] The present invention relates to respiratory, or ventilation, apparatus comprising a face mask and means for supplying pressurised air thereto, as well as to valves useful in such devices.
[0003] Non-invasive, mask-type ventilators, which include a face mask, pressurised air supply and valve, are known. These ventilators suffer from various disadvantages, primary amongst which is inflation of the abdomen via the oesophagus. As the stomach becomes inflated, this pushes up the diaphragm which, in turn, reduces lung volume and, concomitantly, tidal volume (V t ).
[0004] In addition, the ventilators of the prior art are not only cumbersome, but substantially restrict movement of the patient, as the pressurised air supply involves a length of tubing running from the mask to a fixed source of air or other suitable, breathable gas supply. The mask and tubing arrangement also tends to be heavy and somewhat inflexible, thereby putting further strain on the patient.
[0005] The substantial length of the tubing also tends to add somewhat substantially to the dead space. In this context, the dead space is that volume of air involved in the overall tidal flow which never comes into contact with gas exchange surfaces, in particular, the alveoli. When a patient is breathing normally, the dead space mainly comprises the trachea, nose and pharynx which, together, form about 150 ml of a total 600 ml tidal volume.
[0006] Using a mask of the prior art, the air supply tube may have a 10 mm internal radius and a length of 1800 mm, which provides an extra dead space, in addition to the 150 ml naturally occurring, of about 558 ml, thereby virtually doubling the tidal volume, as well as at least doubling the pressure required to effect satisfactory ventilation. It is such pressures which lead to problems with gas build up in the stomach.
[0007] One solution to the problem is to increase tidal flow and to create leaks in the mask to allow exhaust air, rich in carbon dioxide, to escape to help reduce the dead space problem. Another option is to provide a valve in the tubing to allow exhaled air to escape at an earlier stage. Both of these options still require substantial pressure to achieve satisfactory ventilation.
[0008] To achieve exhaust of CO 2 in current masks, continuous positive flow and, therefore, pressure is required, even during exhalation of the patient. The pressure required to achieve this flow is around 8 cm H 2 O or greater. This forms the basic expiratory pressure which the patient faces at exhalation and which needs to be overcome in order for the patient to exhale. This pressure increases the work of breathing and distends lung volume, potentially beyond the need of the patient, while at least the same amplitude (the difference between peak inspiratory and trough expiratory pressures) is required to achieve adequate tidal volume, so that 0-10 cm H 2 O for a normal patient becomes 8-18 cm H 2 O (or more) for a patient using a face mask. The effects may be even more deleterious, as tidal volume of 0-10 cm H 2 O is greater than 8-18 cm H 2 O due to the lung pressure-volume curve.
[0009] One type of mask ventilator providing positive pressure ventilation, and which is non-invasive, is disclosed at page 609 of “Respiratory Care Equipment”, 2 nd edition, 1999. A valve therein relies on natural exhalation, so that it is activated by expiration to cut off or reduce the supply of positive pressure, thereby enabling the patient to breathe out. In this type of ventilator, only one phase of the respiratory cycle, the inspiratory phase, is assisted and therefore active. This has the disadvantage that it is not possible to increase the respiratory rate above 4-30 cycles per minute, as there is no option to do anything other than rely on the natural expiration of the patient. As passive recoil generally requires a minimum of one second, this means that such ventilators cannot work at more than 30 cpm. There is an exhaust valve in the power unit, so that dead space is still a problem, and there is a single pressure chamber through which air from the blower passes, either to the patient during inhalation, or through an exhaust, during exhalation in order to reduce or cut off supply.
[0010] Swiss Patent no. CH685678 discloses an inhaler comprising a base-shaped container in which pressurised oxygen is stored. French Patent Application No. FR2446115 discloses a resuscitator, which fits over the mouth of the patient to supply air from a bulb, further comprising a tongue depressor. Pressure, created by a hand-operated airbag or bulb, forces air into the mouth of the patient.
[0011] U.S. Pat. No. 3,216,413 discloses a hand-operated concentric bellows-type resuscitator apparatus for artificial respiration without a hose, wherein one bellows is situated within a second bellows, and there is an arrangement of valves to enable assisted inhalation and exhalation of air from the patient's lungs at the appropriate pressures.
[0012] U.S. Pat. No. 3,939,830 discloses a manually operated resuscitator or dechoker for removing an obstruction from the throat of a patient. In and out strokes of a piston are used to inflate and deflate the lungs of the patient.
[0013] US Patent Application no. 2003/0111074 discloses a positive pressure hood comprising a power operated blower which forces air through a filter in order to generate a positive pressure within the hood. A one-way purge valve exists for the exhaust of exhaled gases. The apparatus is only suitable for maintaining a clean air supply, for instance in a laboratory or other contaminated environment, inside the hood and, therefore, is not suitable for respirating a patient
[0014] European Patent Application no. 0 352 938 discloses a powered respirator comprising a motor driven fan unit which draws air through an upstream filter unit, or alternatively, forces air through a downstream filter unit, for delivery to a face piece. The fan is triggered by a pressure sensor, which detects inhalation or exhalation by the patient leading to a corresponding assistance by the fan. Therefore, this device requires the patient to be breathing in the first place and cannot, therefore, be considered a respirator.
SUMMARY
[0015] The object of the device disclosed in European Patent Application No. 0 352 938 is to save battery life by only triggering the fan when inspiration is required. This is achieved by matching fan output to the inhalation of the user. Furthermore, the apparatus comprises significant dead space of its own, as can be seen in FIG. 1 , with the associated problems this entails, as discussed above.
[0016] Surprisingly, it has now been found that, by substantially reducing the length of the air supply hose, problems associated with high pressures can be alleviated.
[0017] Thus, in a first aspect, there is provided respiratory apparatus comprising a ventilation mask and means for supplying breathable gasses, under pressure, thereto and means for exhausting gases therefrom, characterised in that the pressuring means is provided substantially at the inlet of the mask.
[0018] By supplying the pressurising effect at the inlet of the mask, rather than at a distance through a tube, the creation of a substantial amount of dead space is avoided, and substantially lower pressures and flow are effective to achieve ventilation, given that less CO 2 needs to be flushed out, as there is little or no tube. Indeed, it is now possible to use sufficiently low pressures that portable, battery operated devices can be employed and worn by patients, thereby allowing substantially unfettered movement, where the patient is capable.
[0019] In order to provide the required pressure at the mask interface, a suitable fan pump may be provided. The fan may be driven directly by a power supply and motor co-located therewith. Alternatively, the power supply, for example in the form of batteries, may be provided elsewhere, such as in a pocket. It is also feasible for the motor to be provided at a distance, and linked by a suitable gear link or train to the fan.
[0020] In general, it is preferred that a lightweight, motorised air pump be provided, mounted directly on the mask, with a remote power supply connected, for example, by suitable cables, or other means. Suitable pumps are centrifugal impeller blowers, of the type illustrated at the website of rietschle, principles/radial.asp, suitably miniaturised, or otherwise adapted, to provide a preferred maximum flow of 50 L/min. This contrasts with the 180 L/min used in the art, and reflects the benefits of the present invention, as well as enabling a portable power source to be used.
[0021] It is preferred that the maximum inspiratory pressure output be in the region of 25 cm H2O, with a range of 5-12 cm H 2 O being preferably employed, in use. Again, this compares extremely favourably with the standard 15-20 cm H 2 O and up to 30-35 cm H 2 O used in standard mask ventilators. The pressures used in the present invention are considerably more effective than those used in the art, as dead space and tidal volume problems are minimised, and there is much better response at lower pressures, as seen in pressure volume curve. It is preferred that the pumps used in the present invention have a voltage requirement of no more than 24V, preferably no more than 15V, with a range of 6-12V being preferred, although any pump or impeller capable of providing the requisite flow may be used.
[0022] The air supplied for breathing by the patient may simply be atmospheric air, in which case there is not generally any requirement for a supply, other than an atmospheric supply. However, where any other form of breathable gas is required or desired, then this may be supplied in any suitable fashion to the pump or, if only required in less than 100% quantities, independently of the pump.
[0023] The exhaust means may comprise a simple valve in the mask which is not generally activated by the pressure generated by the pump, alone, but is only activated by exhalation of the patient.
[0024] Whilst this embodiment provides many advantages over the prior art, it is generally preferred to enhance the respiratory apparatus of the invention by further incorporation of a valve to regulate air, or gas, pressure supplied to the mask.
[0025] It is also preferred to employ both the inlet and exhaust ports of the pump when providing ventilation in association with such a valve. Particularly suitable pumps for use in this connection are lightweight, centrifugal pumps, such as illustrated above, which draw air in at, or near, the rotational axis of the fan and generate an increased air pressure at the perimeter of the rotor, or impeller, which can be expressed via a suitable port. In an advantageous embodiment, both the inlet and the outlet ports of a centrifugal fan are provided in the same face of the pump. This has the advantage of facilitating interaction with the valve.
[0026] It is a particular advantage of this aspect of the present invention that it is possible to fully control the I/E Ratio (the inspiratory to expiratory time ratio), as there is no dependency on passive recoil of the lungs, so that both phases of the respiratory cycle may be fully controlled and active, allowing the I/E Ratio to be varied to practically any desired level.
[0027] Suitable valves of the present invention may comprise two body portions separated by a rotatable valve plate. A first body portion interacts with the ventilation mask, and may be secured thereto by any appropriate means, either fixedly or removably. Where the body portion is removable, attachment may be by any suitable means, such as interference fit, push fit or snap fit, for example.
[0028] The first body portion preferably defines a mask access chamber connecting both to the interior of the mask and the valve plate, and an exhaust chamber having an outlet to the atmosphere and connecting with the valve plate, but not the ventilation mask. Communication between the two chambers is generally prevented by the valve plate.
[0029] The valve plate locates over the first valve body and has openings to provide communication between the chambers of the first valve body and the second valve body portions. Movement of the plate, such as by rotation, serves to define how the chambers of each valve body portion communicate with the other. For ease, the openings in the valve plate are generally sectorial and identical in size, and it is preferred that the valve plate works in a back-forwards, or contra-rotatory, motion, in this case allowing complete control of the I/E ratio to be achieved through control of the time spent in the different sections of the valve. As such, it is also generally preferred that the valve section or, at least that part containing the valve plate, is circular, although it will be appreciated that the housing and walls surrounding the valve may be any appropriate configuration, as desired, and may have any appropriate configuration suitable to manual manipulation, for example.
[0030] It is preferred that the valve plate be mounted on a spindle or other actuatable means suitable to effect movement to locate the apertures in the plate in conjunction with the appropriate chambers in the valve body portions. The spindle may be actuatable by a second motor means, for example. This second motor is preferably controlled and may be responsive to the patient (in a triggered or synchronised mode) or external settings (in a controlled mode).
[0031] When responsive to the patient, exhalation may trigger the plate to move to allow or encourage exhalation. Similarly with inhalation, as both phases of the respiratory cycle may be fully and actively controlled. Suitable detector elements located in the mask can provide a signal to an effector associated with the motor.
[0032] Alternatively, the pump may be controlled independently of the patient's breathing, and set to a certain required pressure, for example. With the valves of the invention, the speed and number of cycles can be determined and this can readily exceed 1000/minute cpm or even higher.
[0033] The second valve body portion comprises at least two chambers, one of which is enclosed and corresponds to the pressurised air, or gas. The other chamber serves as a conduit for exhaust air. Both chambers are located to communicate with the chamber in the first body portion communicating with the mask, depending on the positioning of the valve plate. Where it is desired that the patient should simply exhale, and not be subject to any pressure, either positive or negative, then the exhaust chamber in the second valve body portion may be open to the atmosphere. This chamber, or a further chamber, may be connected to the inlet of the pump, in order to subject the patient to negative pressure to encourage exhalation, in which case it will be appreciated that the chamber will connect only with the inlet of the pump on the one hand and the connecting chamber of the first body portion on the other hand, when the valve plate is in the correct configuration.
[0034] In a preferred embodiment, a valve of the invention has three possible settings, providing the patient with positive pressure, negative pressure or simply atmospheric pressure. In this embodiment, the second body portion of the valve will comprise at least three chambers. A fourth, null chamber, or simple land, may be provided opposite the atmospheric chamber, for example. Where a null chamber is provided, this may be open, if desired.
[0035] It will be appreciated that, when the outlet of the pump is connected to the connecting chamber in the first body portion of the valve, then the inlet of the pump will be connected to the chamber in the first body portion of the valve which connects and, therefore, is exhausted to the atmosphere. Likewise, when the inlet is connected to the connecting chamber, then the outlet will be connected and exhausted to the atmosphere.
[0036] The above pump embodiments are particularly preferred, and form a separate aspect of the invention and, in particular, for use with respiratory apparatus of the present invention, or any other respiratory apparatus.
[0037] The ventilation mask is not critical to the present invention. Conventional masks may be used or adapted, and it is generally preferred that they provide a substantially gas-tight linkage with the airways of the patient.
[0038] The present invention may also be applied to an apparatus where the mask portion is replaced by an endotracheal tube or means for connecting to such a tube.
[0039] Thus, in a further aspect, the present invention also provides a respiratory apparatus comprising a means for conducting breathable gasses directly to the trachea, via a tracheotomy or via a tube through the mouth to the trachea, and a means suitable for supplying the breathable gasses, under pressure, thereto and means for exhausting gases therefrom, characterised in that the pressuring means is provided substantially at the site of the tracheotomy or the patient's mouth.
[0040] The means for conducting breathable gasses directly to the trachea is preferably an endotracheal tube with, optionally, a standard connection from the endotracheal tube to the means suitable for supplying the breathable gasses.
[0041] Alternatively, the means for conducting breathable gasses directly to the trachea is preferably a connecting means for linking the apparatus in a substantially air-tight manner to an existing endotracheal tube.
[0042] The endotracheal tube may be connected to the rest of the device through the patient's mouth and tracheal opening, or, more preferably, through a hole or incision in the patient's throat, for instance a tracheotomy. In this instance, the pressuring means is provided substantially at the inlet of the tracheotomy.
[0043] Thus, this aspect of the present invention is preferably suitable for use in conventional invasive positive pressure ventilation (PPV), for instance on a patient with a tracheotomy. Thus, the apparatus is, preferably, an invasive respirator.
[0044] The apparatus may also be suitably adapted as described in the present application with respect to the mask aspect of the invention. In particular, the apparatus may comprise a valve, preferably as described herein.
[0045] The apparatus can, preferably, operate as either a positive pressure ventilator or a high frequency oscillator.
[0046] There are several advantages to using this aspect of the invention, for instance as an invasive respirator. A direct connection can be made from the apparatus to the endotracheal tube, thus minimising the tubing required. The advantage this gives is again a reduction in dead space during ventilation (although there is already less dead space in PPV than in mask ventilators) and, therefore, lower pressures are required to adequately ventilate patients. Again, this helps avoid the negative side effects of high pressures. Furthermore, as the apparatus can be directly connected to the trachea, this can result in a significant decrease in the dead space associated with the patient's trachea and mouth, for instance as much as 50%.
[0047] The endotracheal tube may also form part of the mask according to the present invention, such that the respiratory apparatus comprises both a mask and an endotracheal tube.
[0048] The apparatus is easy to clean and sterilize, as it has few parts and little or not rubbing, thus reducing the risk of infection for the patient. Furthermore, the apparatus is small, lightweight and this, with the option of being battery operated, allows the invention to be used as a mobile respirator that also takes up far less space when used in the intensive care. Monitoring can be done as in conventional ventilators by sending the information in a wireless manner, such as Bluetooth or infrared, for instance.
[0049] Most mobile transport ventilators are either fairly large battery operated devices requiring substantial amounts of battery power or most commonly (due to this reason) smaller pneumatic devices that require compressed air for them to work. (See chapter 17, Branson et al., “Transport Ventilators,” p527-565, Respiratory Care Equipment).
[0050] Pressures suitable for generation by the apparatus of the present invention are generally low by comparison with the prior art, and suitable pressures have been found, for the mask, to be typically be 5-12 cm H 2 O above ambient pressure and, as a maximum, 25 cm H 2 O during the inspiratory phase and from a maximum of −5 cm H 2 O, to below, at or above ambient pressure during the expiratory phase.
[0051] In the case of the endotracheal apparatus the pressures generated can be higher and are typically from a maximum of 40 cm H 2 O during the inspiratory phase and from a maximum of −15 cm H 2 O, to below, at or above ambient pressure during the expiratory phase.
[0052] These pressures are for guidelines only, and it will be appreciated that higher pressures, as well as lower pressures, may be employed, but these require greater input of power, and may be associated with the problems of the prior art.
[0053] The present invention further provides a method of ventilating a patient, comprising equipping the patient with the apparatus, particularly the mask, as defined above, and activating the pump.
[0054] Preferably, the apparatus comprises a supply of oxygen or breathable gasses, for instance in a pressurised vessel or tank, or via a connection to a source of said gasses. Preferably, an oxygen supplement is fed through a connection to the apparatus, preferably to the valve, in order to increase FiO 2 (Fraction of Inspired Oxygen) to above room air level.
[0055] Any condition treatable by conventional ventilation apparatus or masks may be treated in accordance with the present invention, and may cover patients with sleep apnoea and lung diseases to those on life support, as may be directed by a skilled physician. Therefore, also provided is a method of ventilating a patient in need thereof, comprising the use of an apparatus according to the present invention.
[0056] Preferably, the apparatus is a respirator or ventilator. It is also preferred that the apparatus according to present invention controls the breathing rate of the patient, rather the apparatus being triggered by the breathing of the patient. Preferably, therefore, according to this embodiment of the present invention, inspiration and expiration are not triggered by the patient of his or her breathing, but are controlled by a suitable control device, such as life support machine, for instance. Accordingly, the present invention may be used on a patient that is not breathing on his or her own.
[0057] In a further embodiment of the present invention, the apparatus may also comprise a filter for removing contaminants, for instance, from the inspired and/or expired air.
[0058] Preferably, the apparatus comprises means for reversibly securing the apparatus to the face or neck of the patient, as appropriate, thereby allowing the apparatus to be held in place and/or used in a substantially hands-free manner, without the patient having to hold it in place. For instance, where the apparatus is a mask, it is preferred that the means for reversibly securing the apparatus comprises at least one or a plurality of straps or ties, suitable for the purpose, that may be passed around the patient's head. The straps or ties are preferably elastic.
[0059] Where the apparatus comprises an endotracheal tube, it is preferred that the straps or ties are suitable for passage around the patient's neck, for instance. The apparatus may also comprise a series of flanges which may be used to secure the apparatus to the patient by means of bandages.
[0060] Preferably, the additional dead space added by the apparatus to that naturally occurring in the patient, is kept to an absolute minimum, preferably 200 ml or less, more preferably 100 ml or less, preferably 50 ml or less, preferably 20 ml or less, preferably 25-50 ml, preferably 10-20 ml, preferably 10-15 ml, preferably 5-10 ml more preferably 10 ml and most preferably 5 ml or less.
[0061] The apparatus is also preferably biphasic such that it not only forces air into the patient's lungs, but also actively expels the air from the lungs, rather than simply allowing the lungs to deflate naturally of their own accord, as is the case in many of the prior art devices. Both phases may be triggered by the patients breathing, or may be under the control of the apparatus, under the control of an onboard processor, or under the control of a further control means, such as a life-support machine, for instance. This has the advantage of providing the user or doctor with a greater degree of control with respect to the inspiration/expiration rate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0062] The invention will now be further illustrated with reference to the accompanying drawings, in which:
[0063] FIG. 1 illustrates a mask and valve of the present invention where the valve has three pressure settings;
[0064] FIG. 2 illustrates a valve of the present invention having two pressure settings;
[0065] FIG. 3 illustrates a valve for use with the present invention; and
[0066] FIG. 4 illustrates an alternative embodiment of the valve of FIG. 1 .
DETAILED DESCRIPTION
[0067] In FIG. 1 , there is shown face mask ( 10 ) having processes ( 20 ) for the attachment of straps, or the like, to secure the mask ( 10 ) over the mouth and nose of the patient (not shown).
[0068] Valve ( 30 ) is shown in three sections ( 40 , 50 , 60 ) and is locatable in aperture ( 25 ) of mask ( 10 ) via flange ( 65 ) of first body portion ( 40 ). Connecting chamber ( 70 ) provides an unobstructed passageway between the inside of mask ( 10 ) and valve plate ( 50 ). Chamber ( 75 ) is sealed by land ( 80 ), and does not provide gaseous communication with the inside of mask ( 10 ). Exhaust slot ( 85 ) provides communication with the external atmosphere.
[0069] Valve plate ( 50 ) is provided with spindle ( 90 ), which locates in corresponding recess ( 95 ) in first valve body portion ( 40 ). Spindle ( 90 ) is suitably equipped with external drive means (not shown) to effect rotation.
[0070] Apertures ( 100 , 105 ) control communication between first valve body portion ( 40 ) and second valve body portion ( 60 ). The periphery of the valve plate ( 50 ) locates on internal flange ( 110 ) in valve body portion ( 40 ), thereby providing a gas-tight seal, or substantially gas-tight seal. It will be appreciated that with the general volume of air flow, it is not necessarily important that the seal be especially gas-tight, provided that any gas getting past the seal does not substantially interfere with the desired ventilation effect.
[0071] Second valve body portion ( 60 ) is equipped with four chambers ( 120 , 130 , 140 , 150 ) equipped with slots ( 123 , 126 , 133 , 136 , 145 , 155 ). Impeller end plate ( 160 ) is shown, with negative pressure port or inlet ( 165 ) and positive pressure port, or outlet ( 170 ). The rest of the impeller is not shown. Positive port ( 170 ) corresponds with chamber ( 120 ) of second valve body portion ( 60 ), while negative port ( 165 ) corresponds with chamber ( 130 ). When aperture ( 100 ) is located over aperture ( 133 ), then aperture ( 105 ) will be located over aperture ( 123 ). In this configuration, negative port ( 165 ) communicates via aperture ( 133 ) and aperture ( 100 ) with communicating chamber ( 70 ) to reduce the pressure in mask ( 10 ). At the same time, positive pressure port ( 170 ) acts via apertures ( 123 , 105 ) to exhaust via slot ( 85 ) in dead end chamber ( 75 ).
[0072] Rotating the valve plate ( 50 ) to engage aperture ( 100 ) with aperture ( 136 ) places aperture ( 105 ) in conjunction with aperture ( 126 ), so that the reverse effect is achieved. Namely, negative port ( 165 ) communicates via apertures ( 136 ) and ( 100 ) with null chamber ( 75 ) to draw in air through slot ( 85 ) while positive pressure port ( 170 ) communicates via apertures ( 126 ) and ( 105 ) with communicating chamber ( 70 ) to raise the pressure in the mask ( 10 ). It will be appreciated that the same effect will be achieved if aperture ( 105 ) corresponds to aperture ( 136 ) rather than aperture ( 126 ), and that the one configuration of the two possible is described for purposes of simplicity. Similar considerations apply to any other configuration where a plurality of equivalent possibilities exists.
[0073] In a third configuration, apertures ( 105 ) and ( 100 ) interact with apertures ( 145 ) and ( 155 ), respectively. In this configuration, as with all other configurations of this embodiment, neither chamber ( 150 ) nor open chamber ( 140 ) corresponds to any port on the impeller. Thus, in this configuration, the effect is to provide a direct atmospheric link to the mask via connecting chamber ( 70 ) and apertures ( 100 ) and ( 145 ), the lack of wall in chamber ( 140 ) providing immediate access to the atmosphere.
[0074] In FIG. 2 , valve ( 30 ′) is shown, consisting of first valve body portion ( 40 ′), valve plate ( 50 ′) and second valve body portion ( 60 ′). In this embodiment, the numerals have the same meanings as in FIG. 1 .
[0075] An alternative version of the first valve body portion ( 40 ′) is shown, in which the chamber ( 75 ) is not hollowed in any fashion, thereby simply providing an aperture ( 85 ) communicating with the atmosphere, in the chamber.
[0076] In second valve body portion ( 60 ′), chambers ( 140 ) and ( 150 ) are not present, so that only positive pressure chamber ( 120 ) and negative pressure chamber ( 130 ) are provided. In this configuration, negative pressure is provided to the ventilation mask when aperture ( 100 ) corresponds with aperture ( 133 ) and aperture ( 105 ) corresponds with aperture ( 123 ). Positive pressure is provided when aperture ( 100 ) corresponds with aperture ( 126 ) and aperture ( 105 ) of the valve plate ( 50 ′) corresponds with aperture ( 136 ).
[0077] In FIG. 3 valve ( 30 ″) is for use with a blower where only the positive pressure outlet engages with chamber ( 120 ) of valve body portion ( 60 ″). Chamber ( 130 ) is open to the atmosphere. There is no slot ( 85 ) in valve body portion ( 40 ″). Instead, chamber ( 72 ) connects directly to opening ( 123 ) in valve body portion ( 60 ″) when opening ( 105 ) in valve face plate ( 50 ″) is appropriately located.
[0078] When opening ( 105 ) corresponds with opening ( 133 ), then positive pressure is fed into the mask via chamber ( 70 ), while chamber ( 72 ) is closed by valve face plate ( 50 ″).
[0079] Valve face plate ( 50 ″) may also occupy a central position where slot ( 105 ) corresponds to neither opening ( 123 ) nor opening ( 133 ), so that air may neither pass in nor out of the mask in this configuration. This may be appropriate between inhalation and exhalation, for example.
[0080] As with FIGS. 1 and 2 , recessed portion ( 180 ) locates within and abuts against lip ( 185 ) on valve body section ( 40 ″).
[0081] FIG. 4 depicts a valve embodiment similar to that of FIG. 1 , and functions in a similar manner. In this embodiment, valve body portion ( 40 ″') is lacking land portion ( 72 ) such that, when any of openings ( 136 ), ( 155 ) and ( 123 ) is exposed by either of openings ( 100 ) and ( 105 ), then direct contact with the ambient atmosphere is made.
[0082] Chamber ( 70 ) in body portion ( 40 ′″) takes the form of a lumen in male member ( 75 ) which docks with female member ( 78 ) in the mask ( 10 ). Openings ( 126 ), ( 145 ) and ( 133 ) communicate with lumen ( 70 ) when exposed thereto by either of openings ( 100 ) and ( 105 ) via chamber ( 72 ) recessed beneath flange ( 110 ), providing positive, negative or atmospheric pressure, as desired.
[0083] It will be appreciated that variations are possible in the embodiments of the above Figures and that it is possible to vary the amount of pressure in the mask by varying the degree to which any particular aperture is open. For example, it may be desirable to continue to provide a lesser positive pressure during exhalation rather than atmospheric or negative pressure. Where desired, this may be effected either by lowering pressure in the blower, or preferably by controlling pressure through the I/E Ratio, thereby maintaining an overall positive pressure in the mask, even where the disc is allowing atmospheric or negative pressure into the mask. Although it is possible to vary the speed of the impeller, it is generally preferred to keep this at a constant rate, except when the ventilation device is switched off, in order to conserve energy and provide the most rapid possible reaction time. | Provided herein is a respiratory apparatus comprising a means for conducting breathable gasses directly to the trachea of a patient, via a tracheotomy or via a tube through the mouth to the trachea, and a means suitable for supplying the breathable gasses, under pressure, thereto and means for exhausting gases therefrom, characterised in that the pressuring means is so located as to impart pressure to said gasses immediately adjacent the site of the tracheotomy or the patient's mouth, thereby substantially reducing the length of the air supply hose to an endotracheal tube, so that problems associated with high pressures and large volumes of dead space can be alleviated. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a control valve assembly with either one or two control valves designed as an independent modular unit for a high-pressure fuel injector for an internal combustion engine, particularly diesel engines.
[0003] 2. Background Art
[0004] A fuel injector for an internal combustion engine such as a diesel engine, which includes a unitary control valve module with a single control valve and a single stator core in aligned, stacked relationship with respect to an injector body and a nozzle assembly, is disclosed in copending U.S. patent application Ser. No. 10/197,317, filed Jul. 16, 2002. That application is assigned to the assignee of the present invention. Injectors of this kind comprise precisely machined components or modules that can be assembled with minimum fuel leakage using efficient assembly steps during manufacture. The injector precisely controls the quantity and the timing of the fuel injected into the combustion chamber of an internal combustion engine under the control of an electronic engine controller. The injection events are matched to the engine cycle to provide minimum brake specific fuel consumption and to reduced undesirable exhaust gas emissions.
[0005] Fuel injectors of the kind disclosed in the copending patent application identified above include a high-pressure pump plunger that is stroked by a cam follower driven by a camshaft for the engine. The plunger cooperates with a plunger bore in a pump body to define a pumping chamber that is in communication with a control valve. The control valve is movable between an open position and a closed position to establish pressure pulses in a nozzle assembly of the injector. The valve is carried by an actuator armature situated adjacent an electromagnetic stator in a stator core plate. As the engine controller varies the current of stator windings, variable forces are transmitted to the control valve to effect appropriate shaping of fuel flow rate during each injection event to achieve optimum engine performance with reduced undesirable engine exhaust emissions.
[0006] German Patent Publication WO 02/3142 A1 and copending U.S. patent application Ser. No. 10/196,894, filed Jul. 16, 2002, disclose fuel injectors having two control valves, each of which is controlled by a separate electromagnetic valve actuator. That copending application also is assigned to the assignee of the present invention. The manufacture of such dual valve injectors, as well as single valve actuators, requires precise, close-tolerance machining of valve body surfaces and drilling of multiple pressure passages. The passages typically are relatively long, which increases the manufacturing difficulties. In dual valve injector assemblies of the kind shown in copending U.S. patent application serial No. 10/196,894, the actuators are assembled within a common control valve body. This presents a further manufacturing problem because of the difficulty in accessing critical surfaces of the control valve body that must be machined.
SUMMARY OF THE INVENTION
[0007] The present invention simplifies the manufacture of an injector by replacing costly and highly demanding grinding operations in bores by easily manufacturable flat grinding operations. Since the now shorter control valve module allows for different drilling angles, sharp deflections of fuel columns with the resulting hydraulic disadvantages can also be avoided. Further, unlike manufacture of known injector designs, ECM operations are not required to smooth and round the intersections of connecting bores. This contributes significantly to module strength and durability.
[0008] Particularly with dual control valve designs, routing and attaching electrical coil lead wires to an external connector is not as challenging with the design of the present invention. A separate stator core plate facilitates this because the magnet cores are still accessible after installing the stator core plate into the injector body. The coil lead wires then can be readily attached to external connector wires; e.g., by crimping or welding.
[0009] With the design of the present invention, each control valve seat is closer to the control valve module surface. This allows for the use of more rigid grinding tools, resulting possibly in smaller tolerances of the control valve seat geometry in the control valve module. Because the stator core plate is separate from the control valve module, it is also possible to integrate the stator core plate into the injector body. This would eliminate another demanding grinding process in a bore. However, the control valve stroke of at least one control valve would need to be set with a categorized shim during the assembly process rather than grinding the stroke into the valve during the grinding process.
[0010] The injector of the present invention comprises a control valve module that is independent of actuators of an actuator module or stator core plate. The control valve module is situated in stacked, adjacent relationship with respect to a guide plate adjacent a nozzle nut assembly. The stator core plate, the control valve module, the guide plate and the nozzle nut assembly are assembled together with an injector body to form an integrated fuel injector.
[0011] The control valve module can be machined prior to assembly of the injector in a separate machining operation. The guide plate is interposed between the nozzle nut assembly and the control valve module, the relative angular position of one with respect to the other being indexed so that passages formed in the control valve module are aligned with passages formed in the guide plate, the latter being separately machined.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 is a cross-sectional assembly view of a dual valve injector of the kind disclosed in copending patent application Ser. No. 10/196,894, previously identified;
[0013] [0013]FIG. 2 is a cross-sectional view of a control valve module and a stator core plate, which may be assembled in a manner similar to the assembly of the design of FIG. 1; and
[0014] [0014]FIG. 3 is an end view of the valve body of FIG. 2 as seen from the plane of section line 3 - 3 of FIG. 2, wherein the underside of the valve module body is illustrated.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] To provide an understanding of the mode of operation of the fuel injector of the invention, reference first will be made to the injector of FIG. 1. The injector of FIG. 1 does not include the features of the invention illustrated in FIG. 2, but the mode of operation of the injector of FIG. 1 is generally common to the mode of operation of the injector of the invention.
[0016] The design of FIG. 1 includes an injector body 10 , which has a cylindrical plunger bore 12 in which a pump plunger 14 is situated. The upper end of the plunger 14 carries a cam follower assembly 16 , which is engaged by an engine camshaft-operated actuator (not shown). A spring seat 18 formed on body 10 is engaged by plunger spring 20 , the upper end of which engages cam follower 16 . Cam follower guide 22 is located within the spring 20 .
[0017] The cylindrical bore 12 and the plunger 14 define a high pressure pumping chamber 24 , which is in fluid communication with high pressure delivery passage 26 . This passage communicates with passage 44 in guide plate 42 , with passage 28 in spring cage 30 , with passage 43 in stop plate 45 and with nozzle passage 32 in nozzle body 34 .
[0018] Fuel injection orifices 36 are formed in the tip of nozzle body 34 . They are opened and closed by a nozzle needle valve 38 . A nozzle spring 40 , which is seated on guide plate 42 , urges needle valve 38 in a downward direction as viewed in FIG. 1. Guide plate 42 has a passage 44 , which communicates with the previously described high pressure delivery passage 26 .
[0019] A first control valve 46 , hereinafter referred to as the main control valve, is positioned in a valve bore 48 in control valve body 50 . A second control valve 52 , hereinafter referred to as the nozzle control valve, is positioned in valve bore 54 .
[0020] Passage 26 communicates with annular space 56 adjacent main control valve 46 through internal passage 57 . Main control valve 46 carries an armature 58 positioned directly adjacent a stator 60 with an air gap there between. When the actuator for main control valve 46 is de-energized, the valve is open and the valve stroke is limited by a stop 62 on the upper side of the armature 58 . Annular space 56 has a valve seat 64 on control valve body 50 . When the stator 60 is activated, main control valve 46 is urged against the valve seat 64 . When the stator 60 is deactivated, spring 66 shifts main control valve 46 to the open position, thereby allowing pressurized fluid in passage 26 to be connected to a spill passage 68 . The solenoid windings for the stator 60 are shown at 70 .
[0021] Nozzle control valve 52 is connected to second armature 72 , which is situated directly adjacent second stator 74 . The windings for stator 74 are shown at 76 . Valve spring 78 , seated on stator valve plate 80 , urges the armature 72 and the nozzle control valve 52 in a downward direction, which closes the control valve 52 against valve seat 82 . Thus, the control valve 52 normally is closed by the valve spring 78 against the valve seat 82 when the windings 76 are de-energized.
[0022] The guide plate 42 receives a needle piston or needle valve load pin 84 situated in a piston opening. Load pin 84 extends downwardly and engages a spring seat for nozzle needle valve 38 , as shown at 83 . A pressure chamber on the upper side of the needle valve load pin 84 communicates with high-pressure annular space 54 for nozzle control valve 52 through passage 86 .
[0023] Passage 26 communicates, as explained before, with annular space 56 for main control valve 46 . It also communicates with the upper side of the needle valve load pin 84 through a flow restricting passage 88 .
[0024] Unlike the design shown in FIG. 1, the design of FIG. 2, which incorporates the teachings of the invention, includes a control valve module body 90 , which is separate from actuator module body or stator core plate 92 . The control valve module body and the stator core plate are situated in face-to-face, juxtaposed relationship at an interface shown at 94 when they are assembled in the injector assembly. The interface at 94 can be machined by a single grinding operation throughout the entire width of the control valve module body 90 .
[0025] A nozzle nut or nozzle housing of the kind shown at 87 in FIG. 1 encloses control valve module body 90 and stator core plate 92 .
[0026] As seen in FIG. 2, a main control valve 96 is situated in valve bore 98 , and a nozzle control valve 100 is situated in valve bore 102 . Main control valve 96 has a valve land that engages valve seat 104 , and nozzle control valve 100 has a valve land that engages valve seat 106 . Main control valve 96 is connected to actuator armature 108 , and nozzle control valve 100 is connected to actuator armature 110 . Armature 108 is positioned adjacent the pole face of stator 111 , which has stator coil windings 112 . Armature 110 is situated adjacent the pole face of stator 114 , which has stator coil windings 116 .
[0027] A valve shim 118 carried by nozzle control valve 100 at the upper end of the valve acts as a seat for valve spring 120 . Similarly, a valve shim 122 may be provided for main control valve 96 against which valve spring 124 is seated. A washer spring 126 , is seated against an injector body or against a stator valve plate corresponding to stator valve plate 80 of FIG. 1 when the stator core plate and the control valve module are assembled. It engages the top of stator 114 , as shown at 127 . Stator 114 thus is urged against a calibrated spacer shim 131 so that the armature 110 and the stator 114 are precisely positioned with respect to the ground surface 94 on the control valve module body. The injector body corresponds to the injector body 10 of FIG. 1. The outline of the injector body is shown in FIG. 3 at 162 .
[0028] When the armature 108 is driven toward the pole face of stator 111 as the windings 112 are energized, the valve 96 is closed against the valve seat 104 . Annular space 128 for main control valve 96 is pressurized by high pressure. It is connected to a passage corresponding to passage 26 in the injector of FIG. 1 through internal passage structure (not shown in FIG. 2) in control valve module body 90 . Annular space 128 communicates with fuel injector nozzle feed passage 132 , which communicates with a passage corresponding to passage 28 seen in FIG. 1. Annular space 128 communicates also with passage 134 , which in turn communicates with passage 136 through recess 138 machined in the top surface of the valve module body at interface 94 . A flow restriction 140 in passage 136 is calibrated to provide a reduced and controlled pressure buildup in passage 142 , which in turn communicates with passage 144 extending from the annular space 130 for the nozzle control valve 100 . Passage 142 communicates with the upper surface of a needle load pin of the kind shown at 84 in FIG. 1.
[0029] The stator core plate 92 has separate openings 146 and 148 , which receive, respectively, the stator and the armature for nozzle control valve 100 and the stator and armature for valve 96 . The stator for valve 100 has a central opening 150 , which receives the spring 120 , and the stator 111 for valve 96 has a central opening 152 for valve spring 124 .
[0030] [0030]FIG. 3 illustrates the bottom of the valve module body. Alignment pin openings are shown in FIG. 3 at 154 and 172 . When the control valve module is assembled against a guide plate of the kind shown at 42 in FIG. 1, alignment pins will provide for proper indexing of the control valve module body relative to a guide plate corresponding to guide plate 42 in FIG. 1. Alignment pin openings, one of which is shown at 166 , are formed in control valve module body 98 for receiving alignment pins for indexing the control valve module body 90 relative to stator core plate 92 .
[0031] Annular space 128 for the main control valve 96 , seen in FIG. 2, communicates with spill bore 170 . This bore is only partially seen in the cross-sectional view of FIG. 2 since it generally runs radially outward at an obtuse angle from the axis of valve 96 . It communicates with annular space 128 when the valve 96 is open. When stator 114 is energized, nozzle control valve 100 is unseated from valve seat 106 , thereby allowing annular space 130 to communicate with spill passage 164 , which, like spill passage 170 , is only partially seen in FIG. 2.
[0032] A high-pressure passage corresponding to passage 26 in FIG. 1 extends from a high-pressure pumping chamber corresponding to high-pressure pumping chamber 24 in FIG. 1. It communicates with angularly disposed passages 132 and 134 , seen in FIG. 2.
[0033] As indicated above, FIG. 3 shows the bottom of the control valve module body 90 . The valve module body has two kidney-shaped recesses 174 and 176 , which prevent cross-flow between the valve bores. FIG. 3 shows the valve bore 102 for the nozzle control valve 100 . Likewise, the valve bore 98 for main control valve 96 can be seen in FIG. 3.
[0034] Passage 144 in FIG. 2 extends from the annular space 130 for nozzle control valve 100 . It is an angularly drilled passage, seen also in FIG. 3. The end of the passage 144 is seen in FIG. 3.
[0035] The kidney-shaped recess 174 has a flow-restricting orifice 178 , and the kidney-shaped recess 176 has a flow-restricting orifice 180 . These orifices communicate with a low-pressure port (not shown) in a needle valve housing or nut of the kind seen in FIG. 1 at 87 . That port would communicate with a low-pressure region, such as low-pressure region 182 seen in FIG. 1. The orifices 178 and 180 prevent a pressure buildup at the base of the control valves 96 and 100 . A pressure buildup, if it were to occur, would result in an undesirable leakage from one valve region to the other, thereby interfering with the proper functioning of the valves. The orifices further prevent spill pulses from getting into the kidney-shaped recesses. Any leakage from one valve bore thus will not influence the valve in the other bore.
[0036] The recess shown at 138 at interface 94 in FIG. 2 is easily machined since the control valve module body is made as a separate element of the injector. The passages 134 and 132 , for example, also are easily machined using a drilling operation. Further, notwithstanding the awkward angle of the passage 144 , that passage can be easily machined prior to final assembly of injector.
[0037] The passages in the control valve module can be strategically drilled at locations of maximum material cross-section and strength.
[0038] Passages in the control valve module that intersect (e.g., passages 132 and 134 ) are disposed at a relative obtuse angle, which reduces the deflection of fluid passing through the passages. The drilling of these passages results in a smooth surface at the location of the intersection, and no special deburring operation (e.g. ECM) is needed. The resulting reduction of deflection of fluid in the passages improves fluid flow efficiency because of a reduction in flow disturbances.
[0039] A minimum amount of grinding is required to achieve the desired flatness of the surfaces at interface 94 . The grinding operation is easier than a corresponding grinding operation for the design of FIG. 1 because the surface being ground is not at the base of a stator bore. Similarly, the desired flatness at the base surface 184 , seen in FIG. 2, can be achieved by a simple grinding operation.
[0040] Complex grinding is not required in the valve bores, unlike the case of an integrated design such as that shown in FIG. 1. Further, the shims 131 and the shoulder shown at 186 in FIG. 2 facilitate fitting of the valves within the valve openings, thereby achieving a desired air gap at the armature and proper valve positioning with respect to the valve seats for the control valves 96 and 100 . Easier, faster and more precise drilling and valve grinding operations thus are possible because of the separate stator core plate and control valve module of the invention.
[0041] The advantage in drilling operations is due in part to the shorter drilling distances that are needed.
[0042] Although an embodiment of the invention has been described, modifications may be made by persons skilled in the art without departing from the scope of the invention. All such modifications and equivalents thereof are intended to be covered by the following claims. | A fuel injector comprising a pumping chamber pressurized by an actuator responsive to an engine controller for delivering pressurized fuel from the pumping chamber to a control valve module to control pressure applied at the outlet of an injector nozzle. The control valve module includes at least one control valve. Valve actuators are in a stator core plate that is independent of the control valve module. Machining operations during manufacture of the injector are simplified by a separation of the stator core plate and the control valve module. Mating, juxtaposed surfaces of the control valve module and the stator core plate are fixed by an indexer. | 5 |
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 13/021,607, filed Oct. Feb. 4, 2011, which claims the benefit of 61/301,959, filed Feb. 5, 2010, the subject matter of which is incorporated herein by reference.
BACKGROUND
[0002] Convenience beverage vending is a multi-billion dollar major industry world-wide. Today, market share is totally dominated by beverages sold in plastic bottles and aluminum cans. It is estimated that less than 15% of such beverage containers are currently recycled, leading to huge environmental waste
[0003] In addition, most convenience beverages are predominately water, and consequently, there is a significant embedded energy in their bottling, transportation and distribution into the vending machines themselves.
[0004] There is a need for a new type of beverage vending that addresses the selection limitations and environmental concerns related to existing beverage vending machines.
SUMMARY
[0005] A convenience beverage vending machine and methods of dispensing convenience beverages are described. An embedded computer interface that allows customers to vend a wide variety of convenience beverages into their own re-usable containers is utilized. This vending machine is connected to a municipal water source and drain, in a similar fashion to a standard drinking fountain. This allows the bulk of the beverage contents to be supplied to the machine in a highly concentrated form, and mixed into a custom beverage in the machine, rather than transporting the water to the vending site. The municipal water entering, the machine goes through a multi-stage filtration process that is custom tailored to the water quality at a specific location site.
[0006] The vending machine vends beverages that may be made from hot, cold or carbonated water, and everything from plain filtered water, to standard soft drinks, to fully custom beverages that are designed by the customer. Beverage ingredients may be stocked in the machine in one of two ways, both in highly concentrated forms. Beverage ingredients may be in the form of liquid syrups, either in industry standard “bag-in-box” format, cartridges, or in syrup tanks. Beverage ingredients may be in powder form and may appear in bulk powder containers and or low volume containers. Each machine holds a plurality of separate ingredients. Some of these may be standard beverages and the remainder may be separate ingredients including, but not limited to multiple types of real fruit syrup concentrates, regular and low calorie sweetener syrups, multiple types of flavored nutritional supplements, and multiple types of flavor neutral nutritional supplements.
[0007] A human agent or user may approach the invention and present identification. The machine identifies the user as a customer and pulls up that customer's account. Further, the machine may locate a customer based on a global positioning system (OPS) or a proximity sensor and sign the customer in via a mobile device application. If desired, the user may add funds through the machine interface with physical currency or bill the amount necessary, for example, to a credit card. The machine may also pull up a list of that user's favorite or recently vended beverages. The user can then simply order from this list, order plain filtered water, a standard soft drink, favorite or top selling recipes recommended by the machine, or design a totally new custom beverage. In designing a new custom beverage, the user may select flavor types (which may be blended) and their relative flavor intensity. For example, the user could select 30% pomegranate and 70% blueberry, and then vary the intensity from light, like a flavor hinted water, to heavy, like a fruit juice. The user may also select additional sweetener, from a more standard sugar based sweetener, like cane/agave syrup, or a low calorie sweetener, like stevia/citrus extract. Again, the user may select a combination of these in various percentages, and then vary the intensity from lightly sweet to very sweet. Next, the user may optionally select a nutritional supplement mix, like immune boost, energy boost, multi-vitamin, etc., select their relative percentages, and then vary the amount, maybe according to body weight. For example, a child may use less nutritional supplement than an adult. After making all these selections, the beverage is automatically mixed and dispensed into the user's own container. If the user likes the drink, it may be saved to the user's account and stored in the database for future vending or editing to adjust the recipe, in another example, a customer may access a social media outlet, such as provided by Facebook, Inc, headquartered in Palo Alto, Calif., and “drink share” recipes. For example, a customer may access a social media outlet (e.g. Facebook®) via an electronic application such as an iPhone® application, Android® application and/or other electronic application, and “drink share” custom drink recipes. A customer may then choose to have a local machine vend a shared drink recipe discovered from the social media outlet experience. The local machine may be able to vend the requested shared drink recipe by accessing a remote database via an internet connection. For example, a customer may discover a shared drink recipe during a social media outlet experience and save it to a personal account. The personal account may be saved in a remote database, which the machines are able to access and subsequently vend a drink as requested by the customer.
[0008] A custom mix ratio beverage may also be created. Unlike a standard soda machine, which vends the syrup and water base in a fixed ratio simultaneously, the microprocessor control allows any combination of all of the multiple ingredients stocked in the machine to be mixed in variable proportion to each other, and to the base water. Standard soda fountain mix ratios may be pre-programmed so that standard soft drinks may be vended, or completely custom beverages designed by the individual users may also be vended.
[0009] An automatic cleaning cycle, incorporated into a novel vending cycle may also be incorporated. In a standard soda fountain, soda syrup/water mix drips slightly at the end of each vending operation. This causes the dispense area to be sticky and hence, it requires frequent cleaning. A mixing manifold may be incorporated that is first cleaned with an automatic clean cycle. This purges any drips that may have leaked into the manifold during the period between vending cycles. The mixing manifold multi-path solenoid valve on the end that is normally open to the machine drain is connected to the drain. The clean cycle is effectuated with hot water at approximately 190.degree.F. and/or with a cleaning solution such as bleach.
[0010] The vending machine may also be equipped to provide for automated cleaning of valves. Solenoid valves and standard soda fountain dispensing valves alike can become sticky over time, and may fail to open or close correctly. In a standard soda fountain machine, the machine parts are frequently disassembled and cleaned and then reassembled. One embodiment of the vending, machine utilizes a periodic valve cleaning cycle which may be executed via software or through manual control at certain defined intervals based upon events such as elapsed time, or number of vends of given syrup types.
[0011] The vending machine may also provide a unique billing/customer interface that enables the individual customer to create unique beverages and store their favorite recipes in the machine central database. Each machine may be connected via the internet to the main database. As each individual machine may be stocked with different ingredients, the user interface may display drink possibilities that can be made in the specific machine that the customer is using. The system may also enable features such as “parental controls.” This feature may be enabled in machines deployed in schools, where parents may set limits on the number and type of beverages their children can vend, and may put limits on types of beverages or specific ingredients, such as sugar. The parent may also require a specific nutritional supplement in each beverage. In addition, customers may name drinks and submit them to be tried and rated by other customers, and the database may display the top rated/top selling recipes in the machine. The system may also enable features such as “own/operator controls,” For example, the machine may incorporate lockout times. For example, the machine may be programmed to lock the machine to students during class times, while remaining open to teachers and/or staff.
[0012] The vending machine may also be able to vend beverages into containers of all different sizes, colors and translucencies. Often opaque containers are difficult to see through during beverage filling causing overfilling and spills. If the user knows the bottle/container size, they can select the appropriate size/amount of total beverage, and the microprocessor may adjust the quantities of all ingredients automatically and fill the container accurately, without overflowing the container. If the user makes a mistake, and does not know the size of the container, a manual or microprocessor controlled cycle may be activated to circumvent overfilling.
[0013] The vending machine may also provide the user with a safe experience. Since the machine may be used to vend hot, cold or carbonated beverages, there is a risk that some customer may vend a hot drink into an unsuitable container, such as a stainless steel bottle that is not insulated, potentially causing burns. For this reason, the vending machine may incorporate a temperature sensor. If the temperature on the surface of the bottle exceeds a sate level, the user may be alerted and the vending process halted.
[0014] Dispense area sanitation may also be incorporated in the vending machine. Traditional soda fountains utilize a dispense nozzle which is activated by pushing a disposable cup up against the dispense valve lever. If users were to use their own containers with this type of dispense mechanism, bacteria may be transmitted to the dispense lever and consequently between successive customers. In one embodiment of the vending machine, a recessed dispense tube may be utilized which is shielded so it cannot come in contact with users bottles, and the entire dispense area may be flooded with an anti-bacterial Ultra-Violet sterilization light.
[0015] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The detailed description is described with reference to accompanying figures. In the figures, the left-most digit(s) of a reference number identities the figure in which the reference number first appears. The use of the same reference numbers in different figures indicates similar or identical items.
[0017] FIG. 1 is a schematic of an implementation of the plumbing system in the vending machine apparatus.
[0018] FIG. 2 is a schematic on an implementation of the electrical system in the vending machine apparatus.
[0019] FIG. 3 is a depiction of an implementation showing the locations of components in the vending machine apparatus.
[0020] FIG. 4 is a depiction of an interface presented to the human agent to effectuate the dispense of a custom beverage.
[0021] FIG. 5 is a depiction of an interface presented to the human agent to effectuate the dispense of a custom beverage.
[0022] FIG. 6 is a depiction of an interface presented to the human agent to effectuate the dispense of a custom beverage.
[0023] FIG. 7 is a depiction of an interface presented to the human agent to effectuate the dispense of a custom beverage.
[0024] FIG. 8 is a depiction of an interface presented to the human agent to effectuate the dispense of a custom beverage.
[0025] FIG. 9 is a depiction of an interface presented to the human agent to effectuate the dispense of a custom beverage.
[0026] FIG. 10 is a flow chart depicting the control process relating to beverage vending in an implementation.
DETAILED DESCRIPTION
[0027] Referring to the drawings. FIG. 1 shows an implementation of the vending machine apparatus that may include a touch screen display 100 . However, other implementations may include many other means for the delivery and/or reception of information to and from a user such as a keyboard, monitor, human interface device, or visual display. In an implementation, a personal computer (PC) containing a processor or processors and memory 101 may communicate with the touch screen display 100 to receive and transmit information related to the information acquired by the display 100 and/or delivered by the PC 101 . Other implementations may include other means for the delivery or reception of information to a component interacting with the user.
[0028] The PC 101 may convert, received information to a format and/or language for communication with two Programmable Logic Controllers (PLCs) 103 , 104 . Other implementations may include a means to directly and/or indirectly communicate the user's input with one or more controller devices.
[0029] The PC 101 may communicate with two PLCs 103 , 104 via an Ethernet router 102 . The PLCs 103 , 104 may send and receive information to and from the PC 101 which is directly related to the information retrieved from a user and/or the operation of said PLCs 103 , 104 . Other implementations may include single or multiple control devices and/or methods capable of directly or indirectly effectuating the user's desire. In one example, the user may select an option presented on the touch screen display 100 which may then be transmitted to the PC 101 . PC 101 may then interpret the user's input and convert the input to a format and/or language intelligible to the PLCs 103 , 104 . The PC 101 may then transmit information necessary to accomplish the desire of the user to the PLCs 103 , 104 via an Ethernet router 102 .
[0030] In an implementation the PLC 103 controls a relay 105 connected to a solenoid valve 124 to effectuate the controlled flow of fluid and/or gas through the solenoid manifold 113 . Alternative implementations may include single or multiple relays of varying types including solid state relays, polarized relays, latching relays, reed relays, or other means to control or directly influence the actuation of a valve or the flow of fluid. Other implementations may also include single or Multiple, valves actuated by pneumatic, hydraulic, electrical, and/or other mechanical means. For example, the user's input after being communicated to the PLC 103 via the PC 101 and/or Ethernet router 102 may be effectuated by the activation of a relay 105 which activates a solenoid valve 124 allowing fluid to pass for an amount of time directly related to the user's input. Further, the user's input after being communicated to the PLC 103 via the PC 101 and/or Ethernet router 102 may be effectuated by the activation of is relay 105 which activates the solenoid valve 124 allowing fluid to pass for an amount of volume based on feedback from one or more flow sensors directly related to the user's input.
[0031] As illustrated in FIG. 1 , an implementation utilizes a fluid system to effectuate the transportation, filtration, alteration and manipulation of one or more fluids and its properties. Water entering the vending machine apparatus passes through a normally closed safety solenoid valve 106 . Valve 106 allows for the flow of fluid into the vending machine to be terminated at any time. An Ozone generator may be connected to the fluid path exiting valve 106 via a connection. Flow from the fluid path exiting valve 106 may be prevented horn entering the Ozone generator via a check valve. In this implementation, the water passes through a water softening filter 107 to reduce magnesium, calcium, and other dissolved minerals to levels desirable and palatable for human consumption. After the softener 107 , fluid passes through two activated carbon filters 108 orientated in series. The fluid the passes through an ultraviolet (UV) filter 109 before continuing to other components of the fluid system.
[0032] In summary, an implementation may use a four stage filtration process consisting of a softener 107 , activated carbon filters 108 , and a UV filter 109 to effectuate the delivery of water that is palatable and suitable for human consumption. However, other implementations may include varying quantities and Ivies of purification filters necessary to effectuate the delivery of water that is palatable and suitable for human consumption. An implementation may include other means to reduce scale and/or water hardness such as a scale filter. Alternative implementations may omit the use of filtration in the fluid system.
[0033] The inlet fluid path may be divided to flow to several components. One component may be a solenoid valve 110 for controlling the flow of fluid to a hot tank or water heater 111 . Another implementation may use one or more pneumatic, electric, hydraulic, and/or mechanical valves located before and/or after a heater tank to effectuate the flow of fluid to and from a heater tank.
[0034] The flow of fluid into the heater tank 111 may be directly controlled by the actuation of a solenoid valve 110 . Fluid flow to and from the heater tank 111 passes through the inlet port and outlet port respectively. The outlet port may be directly connected to a fluid path that remains at atmospheric pressure at all times. Other implementations may utilize means to effectuate the heating of water such as a pressurized hot tank, instant water heater, or various other heat addition techniques.
[0035] The temperature of hot water may range from about 100.degree.F. to 212.degree.F. This hot fluid then follows a fluid path to a one way valve 112 which prohibits the backflow of fluid toward or into the heater tank 111 . After the one way valve 112 , the hot fluid passes through three manifolds 113 , orientated with one in series and two in parallel, a fluid flow meter, and a 3-way normally open solenoid valve 115 . At this point the hot fluid is diverted to a fluid path connected to the dispensing nozzle 116 or to a fluid path connected to a drain line 117 . Another implementation may include one or more fluid paths which the hot fluid would follow directly and/or indirectly to the dispensing nozzle and/or drain. Yet other implementation may include means necessary to guide hot fluids from a source to a destination in the fluid system resulting in the dispensing and/or draining of said fluid.
[0036] Fluid may also enter a fluid treatment apparatus 118 which possesses the ability to cool and/or carbonate incoming fluid. This vending machine also possesses the ability to cool one or multiple incoming fluids all of which pass through unique fluid paths. Other implementations may include one or more apparatuses to effectuate the cooling and/or carbonating of fluid in the invention.
[0037] Fluid paths exiting the vending machine, such as a path dedicated to chilled fluid flow through a one way valve 112 to prevent backflow, and then to a dedicated solenoid valve 124 located on a manifold 113 may be incorporated. Each fluid path then follows a path similar to that of the hot fluid after entering a manifold.
[0038] Drain valves may be utilized to ensure the ability to drain fluid held by the present invention. Valves may be of a myriad of designs including but not limited to shut-off valves and solenoid valves. FIG. 1 illustrates an implementation of dram valves with a main line drain valve 129 , a hot tank drain valve 130 , a carbonated fluid drain valve 131 , and an ice bath drain valve 132 . Also an ice bath overflow fluid path or drain line 133 could be utilized to maintain on optimal fluid level in said is bath as a component of the chiller 118 .
[0039] The temperature of the chilled product may range from about 60.degree.F. to 32.degree.F. For example, fluid may enter a combination water chiller, carbonator, and syrup chiller designed for soda-fountain style machines 118 . Fluid exiting from the chilled water path then follows a path connected to a one way valve 124 and then to a normally closed solenoid valve located on a manifold. When the solenoid is activated, the chilled water flows through the manifolds 113 , flow meter 114 , and 3-way solenoid 115 directly to dispense. Other implementations may incorporate the use of one or more fluid paths and/or valves to control the flow of fluid from a fluid treatment device such as a water chiller and effectuate the dispense or disposal of said fluid. Carbonated fluid exiting the fluid treatment apparatus may follow a fluid path directly or indirectly connected to the dispense nozzle and the fluid path may be regulated by a device such as a needle valve 134 or through the use of an inline compensator or similar device. In another example, syrup may traverse a syrup chilling line and flow through a manifold 113 , flow meter 114 , and 3-way solenoid 115 to a dispensing nozzle.
[0040] One implementation utilizes a pressurized carbon dioxide (CO.sub.2) tank 119 with outlet pressure regulated to supply a combination chiller/carbonator 118 , product pump 120 , and direct line with CO.sub.2 gas. Other implementations may incorporate various other components requiring pressurized gas for pneumatic actuation, carbonation, direct use, and/or other applications requiring pressurized gas.
[0041] Gas entering a product pump 120 effectuates the operation of the pump and the flow of the product through a fluid path which bisects the product pump 120 . For example, CO.sub.2 gas actuates a pneumatic turbine pump which delivers positive pressure to incoming fluid thus causing the fluid to traverse an outflow fluid path. CO.sub.2 gas may also follow a fluid path terminating at a one way valve 112 connected to a dedicated, normally closed, solenoid valve on a manifold 113 . The flow through the fluid path may be regulated by a component such as a needle valve 135 . The path then continues along a route similar to the chilled fluid as described previously. In other implementations has may follow various routes terminating at a flow controlling component, such as a solenoid valve, pneumatic valve and/or mechanical valve effectuating the dispense or disposal of the gas. In other implementation, CO.sub.2 gas may enter a carbonation tank under pressure where it dissolves into the co-occupying fluid.
[0042] Pneumatically driven product pumps 120 may effectuate the transmission of product fluid from one or more containers to dispense or disposal along a fluid path similar to the chilled fluid as described previously. Alternative implementations may utilize other means for the transmission of product fluid to dispense or disposal via one or more fluid transmission methods such as electric pumps, pneumatic pumps, positive displacement pumps, hydraulic pumps, positive head, and any combination or isolated use thereof.
[0043] One implementation may utilize a combination of solenoid manifolds 113 to control the flow of fluid from unique and separate inflow paths to a common outflow path. For example, a six line manifold may contain six normally closed solenoid valves, each preventing a given fluid from entering the manifold. When a given solenoid valve is energized, fluid that was previously blocked by the solenoid flows through the manifold. Multiple solenoid valves 112 may actuate during overlapping time intervals allowing one or more fluids to enter the manifold through unique fluid paths and depart through a common path. Other means may also be used to achieve the controlled flow of single, and/or multiple fluids through a common exit may also be utilized.
[0044] In another implementation, the vending machine may utilize a normally open 3-way solenoid valve 115 to control the flow of fluid to the dispense nozzle 116 . The solenoid functions such that all fluid passing through an inlet departs through one of two unique outlet paths. When the 3-way solenoid 115 is energized all fluid passing through an inlet departs through an outlet path connected to the dispense nozzle 116 . Other implementations may utilize methods such as a normally closed solenoid or other means by which to control the dispensing of a fluid.
[0045] A sink 121 may be located beneath the dispense nozzle 116 to capture disposed fluid and channels said fluid to a drain 117 . Other implementations may use various methods to capture disposed fluid and pass said fluid to a drain.
[0046] An ultra violet (UV) sanitization light 125 may be utilized to effectuate the sanitization of the sink, dispense nozzle and or the dispense area.
[0047] Fluids may be transmitted to disposal exit through a dram pipe 117 . Other implementations may use methods such as a reservoir with a submersible pump to expel disposed fluid from the invention.
[0048] An inductive float switch 128 may detect the presence of fluid at the base of the invention. Other implementations may use other fluid level sensing means.
[0049] A magnetic stripe card reader 122 may effectuate the transfer of funds from the consumer as payment for products delivered by the invention. For example, consumer approaches the invention and utilizes a VISAR® credit card to purchase a beverage from the vending machine Other means may also be used to effectuate a payment, such as a cash and coin machine or other payment accepting device.
[0050] A near field radio frequency identification (RFID) reader 123 may effectuate the recognition of a known customer and enable the invention to respond to that customer in a personalized manner. For example, a customer approaches the machine and presents an RFID tag to the reader 123 which accepts an identification number from the customer's tag and transmits the information to a program which retrieves and utilizes information associated with the customer's identification number. The RFID tag may be a proximity card, a passive RFID tag, an active REID tag, a Near Field Communications device, or any another REID technology and/or frequency communication device suitable for effectuating the recognition of a known customer and enable the invention to respond to that customer in a personalized manner. Other implementations may use methods such as a user name, password, magnetic stripe card, smart card, and/or any similar method to effectuate the identification of known customers.
[0051] Single or multiple LED lights 126 may be used to illuminate a beverage container located below the dispense nozzle 116 and or for the purpose of illumination in the area where fluid is dispensed.
[0052] A camera 127 may be used to capture images of the path of fluid out of the dispense nozzle 116 . The captured images may be still images and/or video images of the path of fluid out of the dispense nozzle 116 .
[0053] The beverage selection and customization process may utilize a touch screen display 100 to effectuate communication between the vending machine and a user. Such communication enables the user to directly control the composition of a dispensed beverage. For example, FIG. 4 exemplifies an initial display image that an implementation may utilize. The user's identity becomes known to the invention at a “sign in” event. Preceding this event, an implementation may display an image as shown in FIG. 5 .
[0054] An implementation may use display images such as shown in FIG. 4-9 for the beverage customization process. For example, a user utilizes a display image such as shown in FIG. 5 to select a desired drink volume. In one implementation, a beverage volume may range from about six fluid ounces to about sixty four fluid ounces or any similar volume related to a personal beverage container. The user then has option to select a main fluid type such as regular cold water, carbonated water, and hot water. However, other implementations may include main fluid types other than water such as a solution of water and ethanol alcohol. After that, a display screen, such as shown in FIG. 7 , may be used to allow the user to select one or multiple supplemental fluids to add to the beverage. For example, the user selects kiwi, mango and orange fruit juice concentrates to be added to the custom beverage. The user then has the option to customize the ratio in which the supplemental fluids are added. The user may designate that the final combination of supplemental fluid contain 47% kiwi, 28% orange, and 25% mango fruit juice concentrates.
[0055] Other implementations may include similar but different means for the user to customize the specific supplemental fluid to be added. Other implementations may also include similar but different means for the user to customize the ratio in which the specific supplemental fluids are added. For example, a user may choose to create a beverage from multiple supplemental fluids at an infinite variety of ratios with the sum total equaling one or 100%. The arbitrary value of 100% may be associated with a value directly related to the user's desired flavor strength. If a user chooses five supplemental fluids at a flavor strength of “heavy,” were heavy flavoring is known to be equal to one fluid ounce, then the five supplemental fluids may be combined at an infinite variety of ratios with the volume equal to a constant of one fluid ounce. Still other implementations may utilize means other than a total volume approach to enable a user to customize the mix ratios of supplemental fluids. Another implementation may be to set supplement volumes to static volumes or “shots.” The shots may be of the same volume for an 8 oz drink and a 32 oz drink. A user may select one shot or more than one. Such other approaches may include setting the summation of supplemental fluid taste, viscosity, or other properties to meet the desire of the user.
[0056] After selecting supplemental fluids in a unique combination as per the user's desire, nutritional supplements may be added to the beverage through a display image as shown in FIG. 7 . Nutritional supplements in liquid, powder, or other form may be added to the beverage or the total fluid volume dispensed in a fixed quantity, mass, or in a quantity proportional to a property of the beverage or the user's desire. For example, the user may choose a twenty fluid ounce beverage with a nutritional supplement. The total mass of supplement dispensed may be a fixed mass such as one gram. In another implementation, the mass of nutritional supplement may be proportional to the user's desired supplementation or proportional to the volume of the twenty ounce beverage. The user may also have the option of adding a sweetener to the custom beverage. The sweetener may consist of ingredients such as cane sugar. Stevia, agave sugar, or other sweeteners. These sweeteners may be added to the custom beverage in a manner similar to that described for the nutritional supplements.
[0057] The total mass of sweetener dispensed may be directly proportional to the beverage volume and the strength of sweetness desired by the user. Other implementations may include similar means to enable a user to customize the sweetness of a custom beverage. The user may also be presented with a display image as shown in FIG. 8 that informs the user of the final composition of the customized beverage that the user created through the drink customization process.
[0058] At this point in the beverage customization process, the user has the option to confirm the purchase and/or final composition of the custom beverage. The user may also be presented with a display screen, as shown in FIG. 9 , that presents various information to the user. This information may include advertisements which are presented to the user. These advertisements may be generic and/or targeted to the specific users. The display screen may also present social media interaction options. For example, users may choose to share their drink with their friends as their Facebook®, status. Also, the final screen may allow the user to initiate the vending by pressing a button or through similar means of actuation.
[0059] A cleaning cycle may be utilized to ensure proper sanitization and performance. In one implementation, the vending machine may utilize an automated cycle to effectuate the cleaning and sterilization of one or more fluid paths. This cleaning may be effectuated by the circulation of hot water with a temperature of approximately 190.degree.F. and/or a sanitizing fluid such as a bleach solution through one or more of the fluid paths. Another implementation may utilize ozone gas (O.sub.3) to effectuate the sanitization of one or more fluid paths. Other implementations may utilize a similar cleaning cycle effectuated through manual means rather than automated. Also, various methods for determining the necessity of cleaning and sanitization may be incorporated in art implementation to initiate a cleaning cycle. Such methods may include the use of a flow characterization sensor to sense a change in the flow indicative of the necessity for a cleaning cycle. However, other implementations may utilize methods dictating a time interval between cleaning cycles and/or a means for manual determination of the necessity of a cleaning cycle.
[0060] A computing device which includes a process and memory, such as random access memory (RAM), may be utilized. The computing device may be used in combination with other components of an implementation including, but not limited, to a controller and display device. The computing device may operate in combination with connected devices to effectuate the dispense of a customized beverage. The computing device may also perform actions according to software Operating in the device.
[0061] A means to clean and sanitize components exposed to a user interacting with the vending machine for the purpose of beverage vending may also be included. All surfaces exposed to the user are easily sanitized and cleaned. More specifically, areas of the vending machine exposed to fluid through the beverage vending process, hereinafter called the dispense area, are regularly sanitized through a sanitization cycle. In one implementation, the cycle may include an ultra violet (UV) sanitization light 125 to effectuate the sanitization of the dispense area. Other implementations may utilize hot fluid, such as water, at a temperature of approximately 190.degree.F. and/or sanitization fluid such as a bleach solution to effectuate the cleaning of the dispense area. One implementation may activate a UV light after the vending cycle or at some other time for a period necessary to inhibit bacterial growth and that of potential pathogens in the dispense area. In another implementation, a surface in the dispense area may be immersed in sanitization solution to effectuate the removal of harmful bacteria from the dispense area.
[0062] A means to ensure the safe dispense of hot fluid where hot fluid is defined as fluid at a temperature of above 100.degree.F. may also be incorporated. The safe method reduces the risk of burn and/or other related injury to a user. In one implementation, such a safe method is effectuated through the use of a temperature sensor that measures, directly and/or indirectly, the surface temperature of a container. The method may include means to terminate dispense of bot fluid and/or lower the surface temperature in the event that the surface temperature of the container reaches or exceeds a temperature threshold. For example, a user places a metallic container in the dispense area and effectuates dispense of hot fluid. After fluid enters the container, a temperature sensor indicates that the surface temperature exceeds 100.degree.F. The present invention then halts dispense of hot fluid and dispenses cold fluid at a temperature of about 45.degree.F. until the temperature sensor indicates that the surface temperature is below the temperature threshold of approximately 100.degree.F. Other implementations may utilize similar but different methods of detecting unsafe temperature levels.
[0063] A method to determine the volume and/or size of a container into which fluid is dispensed mg also be incorporated. One implementation utilizes an array of proximity sensors located in a pattern to allow for the computation and approximation of container size. For example, one implementation utilizes a various ultrasonic range finders may be arranged in a hemispherical pattern around the container bay to determine the dimensions of a container. An algorithm then transforms dimensional data received from the range finders and calculates approximate container volume. Other implementations may utilize means which determine or approximate container volume by measuring other properties, such as mass, without departing from the scope of the present invention.
[0064] A method to verify the presence of a container in the dispense area may also be incorporated. Such a method allows for the vending machine to terminate dispense of fluid in the event that there is no container present into which fluid will be dispensed. One implementation may use an ultrasonic range finder to verify the presence of an object in the dispense area. Other implementations may use various other means to verify the presence of a container into which fluid will be dispensed.
[0065] A method to encourage the alignment of a container opening and the dispensed fluid so as to ensure that dispensed fluid enters the container may be incorporated. One implementation utilizes dimensional sensors and a multi-dimensional actuator to position a dispense nozzle over and above the container opening. Other implementations may use various other methods including a combination of sensors and messages that inform the user of the status of alignment between the container opening and the dispense nozzle. Another implementation may present an image of the dispense nozzle and the container opening to a user and allow the user to effectuate dimensional adjustments to ensure the flow of dispensed fluid into the container.
[0066] A method to prevent the overfill or flow of fluid out of a container opening may be incorporated. Such an event may occur during, the fluid dispense process. One implementation utilizes a dimensional sensor that measures the speed of fluid rise in a container. This implementation may then sense a change in speed of said fluid which may indicate that the container has reached maximum fluid capacity. For example, an ultrasonic range finder indicates that fluid is rising in a container at a velocity of V.sub.o. Then the sensor indicates that the current velocity. V.sub.c, of the fluid has decreased by a given factor, k, or V.sub.o=V.sub.c/k. This decrease in velocity further indicates, by implication, that the fluid is no longer rising in the container and has begun to flow out of the container opening.
[0067] A method to ensure that fluid passing through fluid paths as a component of a clean cycle does not enter a container located below a dispense nozzle may be incorporated. One implementation effectuates this method by incorporating a multi-directional valve which is connected to a drain and to a dispense nozzle. In the event of a clean cycle, the multi-directional nozzle is positioned to ensure that fluid does not flow into the dispense nozzle and instead flows into a drain or re-circulation loop that is part of the clean cycle. For example, before dispensing fluid, a fluid path is filled with hot water at a temperature of approximately 190.degree.F. The fluid path is connected to a normally closed 3-way solenoid valve which controls the flow of fluid either to a dispense nozzle or to the drain. The 3-way solenoid is de-energized and thus all hot fluid entering said valve passes to a fluid path connected to the drain. This ensures that hot fluid does not enter a dispense nozzle. Other implementations may utilize other types of valves or methods to effectuate this method.
[0068] A method to store information on a customer identification device may also be incorporated. In one implementation, the device is a customer's near field radio frequency identification (RFID) tag. In other implementations the device may present itself as a personal communication or entertainment device such as an MP3 player or cell phone. Still other implementations may utilize various other devices capable of passing and storing information.
[0069] In one implementation, information containing information specific to the owner of the device, is sent from the vending machine to the device for storage. This information is then stored for later use by a user and/or the vending machine For example, a customer possesses an REID tag which stores information pertaining to the customer's account balance and beverage preferences. In the event that the customer utilizes the RFID device to identify himself to the vending machine, the information previously described, is passed to the vending machine. The information is then utilized to effectuate the personalization and/or beverage vending experience of the customer. Other implementations may utilize stored information for other purposes relating to the customer experience.
[0070] A method which enables customers to create or modify an aspect of their account and/or view information pertaining to the vending machine through electronic means may be incorporated. In one implementation, this is effectuated through the utilization of an electronic application such as an iPhone® application. Android® application and/or other electronic application. For example, a customer uses an iPhone® application to create a custom beverage and add it to his account. The next time this customer identities himself to an implementation, he may be given the option of dispensing the beverage created on the application. In another example, a customer utilizes an iPhone® application to view locations of the vending machines near that specific customer's location. Other implementations may utilize various other electronic means to effectuate this method. Such other electronic means may include a web site, a social media outlet (e.g. Facebook®) or other information conduit.
[0071] A method to present advertisements to one or more users within a given proximity may also be incorporated. The advertisements may be tailored to a specific user and/or intended for a general audience.
[0072] A method to store customer information in a database may also be incorporated. The database may be utilized by various implementations of the vending machine to share and retain information pertaining to a customer, beverage components, location and various other information that are utilized to effectuate the beverage customization, vending process, and/or customer experience. For example, a database contains information pertaining to volumes of beverage ingredients to ensure that the ingredients are replaced before they empty. In another implementation, the database contains information pertaining to an individual customer's name, beverage history, beverage preferences, affiliations, age, gender, location and other personal attributes. This information is passed from the database to an implementation in the event that a customer identifies himself. The information may be utilized to customize the customer experience and present the customer with known preferences.
[0073] FIG. 10 illustrates a process through which a controller may effectuate the dispense of a customized beverage. In an implementation, the process initializes upon the establishment of communication between all controlling devices 138 . The process continues with the confirmation of successful communion. If successful, the process continues and controller subroutines are activated 139 . Following this, the controller waits to receive data encompassing the information necessary to dispense a beverage 140 . When the information is received, the clean process 144 performs a pre-determined cleaning algorithm which may include the use of hot water to clean lines before dispense. The type of water 141 desired is selected and appropriate dispense volumes are calculated. Then a ratio of the total beverage volume is dispensed and a process determines whether or not syrup was requested. If syrup was requested a pour syrup 145 algorithm controls the dispense of the desired volume of single or multiple syrups. If syrup was not requested or upon completion of the pour syrup process 145 , the remaining beverage volume is dispensed. Following this event the post clean 142 process performs a cleaning algorithm to clean fluid paths and the controller or controllers wait to receive the data necessary to dispense another beverage. At any point in the process described above, a stop command 143 may interrupt the process immediately moving said process to the post clean 142 event.
[0074] Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. | Methods and apparatus describing a convenience beverage vending machine and its operation are described. An embedded computer interface allows consumers to create their own drinks or choose from a menu of drinks. Drinks are dispensed in a re-usable container. The beverages may be made from hot water, cold water or carbonated water that is mixed with various flavors of syrup, sweeteners and nutritional supplements. Identification may be presented and the computer recognizes the consumer and pulls up that consumer's account to determine funds available and previous drink selections and mixtures. The machine may incorporate an automatic cleaning cycle for both the valves and the dispense area. | 6 |
BACKGROUND OF THE INVENTION
During the operation for the removal of a cataract, it is common practice to remove the natural lens of the eye. In years past, because of the absence of the lens, it has been necessary to provide the patient with special eye glasses to at least partially restore his sight. These eye glasses, however, are only capable of restoring a portion of the sight and they are not entirely effective, because they present a very large magnification of the image and because they suffer from a peripheral distortion of sight. Magnification makes "binocular" vision difficult if the other eye is healthy, and the narrow angle of sight results in the so-called "tunnel vision," i.e., loss of side vision.
Besides these difficulties with cataract lenses, it has always been the desire of the medical profession to be able to replace the natural lens wih an artificial lens. Until recently the materials that were available for such lenses (such as glass) have not been compatible with the interior of the eye. In World War II, it was noted however, that, when pilots in an accident received particles of the plastic used in the aircraft windows into the interior of the eye, the particles remained there in suspension without interfering with the operation of the eye or resulting in discomfort to the pilot. As early as 1947, therefore, attempts were made to use this plastic (polymethyl methacrylate) in artificial lenses to be inserted in the eye. Although the earlier attempts were less than successful, nevertheless, as the years went by and techniques for attaching the lens were developed, the rate of success has become fairly high. Although many different designs of artificial lens have been produced, the general approach is to use wire clips or sutures on the sides of the lens which clip through the iris to hold the lens in place. Because the iris must expand and contract and because the inner edge of the iris is often frayed and less than perfect in its construction, these lenses have in many cases fallen out. Their replacement, although an office procedure, is, nevertheless, an undesirable feature of the construction. Attempts have been made to suture the clips to the iris to prevent slippage, but the movement of the iris as it expands and contracts, has a tendency to tear the sutures out. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide an artificial lens having a high probability of success in retention.
Another object of this invention is the provision of a lens implant which is securely located adjacent the iris and, yet, which does not require a perfectly intact iris and does not inhibit the iris movement or cause it damage.
A further object of the present invention is the provision of a lens implant which can be readily applied by a surgeon of moderate skill.
It is another object of the instant invention to provide a method of applying a lens implant which method has a high probability of success.
A still further object of the invention is the provision of a surgical procedure for implanting an artificial lens, which procedure is simple in execution and reliable in result.
It is a further object of the invention to provide a lens implant support mechanism which permits the anchorage of the implant to be more physiologically suitable and allows the placement of the implant in the posterior chamber.
It is a still further object of the present invention to provide a lens implant system which gives reliable, predictable anchorage, irrespective of variations in the nature of the iris from one patient to another; it is particularly useful where the iris is not intact and has operative ability irrespective of whether sufficient iridocapsular adhesions form to support the loops of the implant.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.
SUMMARY OF THE INVENTION
In general, the present invention resides in the provision of an artificial lens for use in replacing the natural lens of the eye and consists of a lens element adapted to lie adjacent the iris. A support arm is connected at one end to the lens element and extends therefrom in a plane generally parallel to the plane of the lens element. The other end of the arm is adapted to be sutured through the ciliary body and the sclera. Means is provided to hold the lens element adjacent the iris without inhibiting the operation of the iris.
More specifically, the support arm has means for suturing to the ciliary body at points which are substantially spaced about the center of the iris and of the lens to prevent tipping of the lens. Two wire elements are located on opposite sides of the lens element and are spaced a substantial distance from the surface of the lens element, so that the lens element resides on one side of the iris, while the wire elements reside on the other side. The support arm is a loop of wire whose ends are connected to the lens elements, the loop being generally U-shaped with the lens element located at the open end and the suture points located in apertures at two remote corners. The suture passes through the ciliary body and also through the sclera, so that it can be tied on the outer surface of the sclera or conjunctiva.
BRIEF DESCRIPTION OF THE DRAWINGS
The character of the invention, however, may be best understood by reference to one of its structural forms, as illustrated by the accompanying drawings, in which:
FIG. 1 is a horizontal sectional view of a human eye, showing an artificial lens incorporating the principles of the present invention,
FIG. 2 is a sectional view taken on the line II--II of FIG. 1,
FIG. 3 is a sectional view of the invention taken on the line III--III of FIG. 2,
FIG. 4 is a sectional view of the invention taken on the line IV--IV of FIG. 2, and
FIG. 5 is a sectional view of an eye showing in use a modified form of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, which best shows the general features of the invention, it can be seen that the artificial lens 10 is shown in use in a human eye 11. The lens is shown as associated with the anterior chamber 21 lying between the cornea 24 and the iris 13. A suture 15 is shown as extending from the lens and passing through the ciliary body 16 and the sclera 23.
In FIG. 2 it can be seen that a lens element 12 lies in the anterior chamber 21 and is provided with a support arm 14 which is connected at one end to the lens element and extends therefrom in a plane generally parallel to the plane of the lens element. The other end of the arm is adapted to be attached by means of a suture 15 to the ciliary body 16. Means, including wire elements 18 and 19 are provided for holding the lens element 12 adjacent the iris 13 without inhibiting its operation. The support arm 14 is provided with apertures 26 and 27 through which the suture 15 passes for connecting it to the ciliary body and sclera at points which are substantially spaced about the center of the iris to prevent tipping of the lens element.
As is obvious in FIG. 3, the two wire elements 18 and 19 reside in the posterior chamber 22 and constitute the means 17 for holding the lens element adjacent the iris. They are located on opposite sides of the lens element 12 and are spaced a substantial distance from the bottom surface of the lens element where it comes in contact with the iris, so that the lens element resides on one side of the iris (in the anterior chamber), while the wire elements reside on the other side of the iris (in the posterior chamber).
The support arm 14 is a loop of wire which, in the preferred embodiment is platinum, whose ends are connected to the lens element. The loop is generally U-shaped with the lens element located at the open end and the suture points located at two remote corners. In the preferred embodiment, the lens element is formed of a polymethyl methacrylate which is substantially free of the monomer. In the preferred embodiment, the lens element is located in the anterior chamber 21 and the suture 15 passes through the ciliary body and the sclera 23 and is tied on the outer surface thereof in a knot 28.
FIGS. 2 and 3 show that the arm 14 is a loop of rod-like material with a generally straight portion 25 extending at a right angle to an imaginary line connecting the center of the lens element 12 to the straight portion. The straight portion extends an equal amount on either direction from the said imaginary line and aperture 26 is formed in the straight portion adjacent the end thereof at one side and an aperture 27 at the other end. As has been stated, the suture 15 extends through the aperture, through the ciliary body 21 and through the sclera 23 and is tied on the exterior of the sclera. In other words, the loop of the arm 14 is generally U-shaped with two straight parallel legs 29 and 31 joined by the bight or straight portion 25 located remotely of the lens element 12. The bight is provided with the substantially-spaced apertures for suturing.
The free ends of the legs 29 and 31 are connected to inclined intermediate members 32 and 33, respectively, which, in turn, are connected to generally transversely-extending guide elements 18 and 19, respectively. The ends of the guide elements 18 and 19 are provided with vertical risers 34 and 35, respectively, the upper ends of which are fastened to the lens element 12.
FIG. 4 shows particularly well the nature of the apertures 26 and 27 and the manner in which the suture 15 passes through them in order to fasten the end of the arm 14 at the spaced points that are defined by the apertures 26 and 27.
The operative procedure for replacing the natural lens of the eye which the artificial lens 10 will now be readily understood in view of the above description. First, the natural lens (which lies in the posterior chamber 22 at the rear of the iris) is removed surgically by means of an incision through the limbus, i.e., the transitional zone between the cornea and the sclera. Through the incision thus made, it is possible then to place the artificial lens in position with the lens element 12 in the anterior chamber 21 adjacent the iris 13. The arm 14 has been inserted through the pupil so that it now lies in the posterior chamber 22 rearwardly of the iris. At the same time, it is positioned so that the holding means 17, consisting of the wire elements 18 and 19, lies in the posterior chamber against the rearward surface of the iris 18. The gap between the wire elements 18 and 19 and the surface of the lens element 12, as it engages the iris, is maintained of a sufficient size to hold the lens in place without inhibiting the normal opening and closing of the iris. Furthermore, the risers 34 and 35 are located close enough together so that when the iris is in its most contracted state, they do not interfere with its operation.
With the lens element 12 in place in the anterior chamber, the arm 14 extends radially of the center of the iris into engagement with the ciliary body 16. In the preferred embodiment, the straight portion 25 of the arm lies in the corner between the ciliary muscle and the base of the iris. In this position the surgeon performs a peripheral iridectomy that gives him an opening through which he can manipulate the suture 15 through the sclera 23, through the ciliary body 16, and through the aperture 27. From there the suture passes around the arm and outwardly again through the aperture 26, the ciliary body 16, and the sclera 23 to the outside. Loose ends are then tied in the knot 28, which knot may be hidden under a flap of sclera or of conjunctiva where it cannot be seen.
The advantages of the present invention will now be readily understood in view of the above description. Because the suture points defined by the apertures 26 and 27 are widely spaced, they prevent the lens from moving relative to the rest of the eyeball despite the expansion and contraction of the iris in its normal operation and the movement of the eyeball in various ways. This effect of tying down the lens firmly to a fixed base is reinforced by the fact that the suture passes through the ciliary body and the sclera which are relatively tough fixed elements in the eyeball and are not subject to expansion and contraction. This makes the effect of applying the lens to the human eye much more predictable and avoids the use of the delicate and sometimes damaged iris as a support member. It is particularly important, since the iris apparently varies from patient to patient. Furthermore, with the present invention there need be no concern as to whether sufficient iridocapsular adhesions form to support the loops of the implant.
In FIG. 5 the lense element 12a lies in the posterior chamber, while support 18a on the anterior side of the iris 13a. The arm 14a is sutured to the ciliary body and the sclera at one side of the iris, while another arm 14b extends to the other side.
In a commercial version of the invention, the lens element 12 is formed of polymethyl methacrylate with very little of the monomer present. The lens element is of plano-convex shape and has a 5mm. diameter with a central thickness from 0.5 to 0.6mm. The loop or arm 14 is formed of platinum iridium and has a length of 5.75mm. from the center of the lens 12 to the straight portion 25 of the loop. It is formed of a rod material which is from 0.15 to 0.2mm. in diameter. In the preferred embodiment, where the loop touches the ciliary body, the loop may be thickened by 0.6 to 1mm., so that the apertures 26 and 27 will fit best. In this embodiment the apertures 26 and 27 were located 2mm. apart. The arms of wire elements 18 and 19 which lie against the iris have an overall length of 4mm. from the center of the lens. The overall length of these arms from tip to tip is 9.75mm. with a clearance between them of 0.5 to 0.75mm.
It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed. | Artificial lens for replacement of natural lens in the eye, wherein an elongated arm is provided for attaching the lens to the ciliary body and sclera and for locating the lens adjacent the iris without interfering with the operation thereof. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This non-provisional patent application claims benefit of provisional patent application U.S. Ser. No. 60/503,046, filed Sep. 15, 2003, now abandoned.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to signaling of TGF-b superfamily. More specifically, the present invention relates to antagonism of signaling of TGF-b superfamily ligands.
[0004] 2. Description of the Related Art
[0005] The transforming growth factor b (TGF-b) superfamily comprise over 30 secreted ligands in human that control cell growth, homeostasis, differentiation, tissue development, immune responses, angiogenesis, wound repair, endocrine function and many other physiologic processes. Members of this superfamily include TGF-b, activins, bone morphogenetic protein (BMP), Growth and Differentiation Factor (GDF) and nodal-related families. Disruption or dysregulation of activin and TGF-b signaling is associated with multiple pathological states including carcinogenesis.
[0006] TGF-b superfamily members share a distinct structural framework known as the cystine knot scaffold. Activin and TGF-b are each disulfide-linked dimmers. Activin consists of two b chains. Although there are several activin b subunit genes and an extensive array of possible b-b dimers, only bA-bA (activin-A), bA-bB (activin-AB) and bB-bB (activin-B) have been isolated as dimeric proteins and shown to be biologically active. Three TGF-b genes exist in mammals giving rise to the TGF-b 1 , TGF-b 2 and TGF-b 3 isoforms.
[0000] Activin and TGF-b Signaling Via Receptor Serine Kinases
[0007] TGF-bs, activins and other members of the TGF-b superfamily exert their biological effects by interacting with two types of transmembrane receptors (type I and type II) with intrinsic serine/threonine kinase activities, called receptor serine kinases (RSKs). Type I receptor serine kinases are referred to as ALK1 to 7, for Activin receptor-Like Kinases. The receptor activation mechanism was first established for TGF-b which was shown to bind its type II receptor (TbRII) leading to the recruitment, phosphorylation and activation of its type I receptor (ALK5). A similar mechanism of ligand-mediated receptor assembly and type I receptor phosphorylation has been demonstrated for activin receptors involving initial binding of activin to ActRII or ActRIIB followed by recruitment, phosphorylation and activation of the type I receptor ALK4.
[0008] The ligand binding properties of the receptor extracellular domains (ECDs) have been extensively examined. The crystal structure of the ActRII-ECD provided detailed information regarding sites predicted to be involved in receptor:ligand interactions. The crystal structure of the ActRII-ECD bound to BMP-7 has recently been solved and it was shown that the amino acids on ActRII required for activin-A binding make up interfacial contacts between ActRII and BMP-7 and are required for BMP-7 binding. An allosteric conformational change was observed in BMP-7 in its predicted type I receptor binding site following binding to ActRII. This suggested a general model for cooperative type I/type II receptor assembly induced by BMPs (or activin) to form a hexameric complex containing the dimeric ligand, two type II receptors and two type I receptors.
[0009] The structure of activin-A bound to the ActRIIB-ECD was also solved recently and was generally consistent with previous findings regarding the activin-A binding site on the ActRIIA receptor. Using the crystal structure of BMP2 bound to the BMP type I receptor (ALK3-ECD) as a guide, an activin-A binding surface on the type I receptor ALK4-ECD was recently identified.
[0010] The structure of TGF-b 3 bound to the TbRII-ECD has also been solved and indicated unexpectedly that the TGF-b binding interface with its type II receptor is very different from the corresponding interface of activin and BMP7 with ActRII. This suggests that although activin and TGF-b have a similar mechanism of receptor activation, they apparently have unrelated ligand-type II receptor interfaces.
[0011] Regardless of the precise mechanism of receptor assembly by TGF-b superfamily ligands, it has been generally established that following receptor assembly, type II receptors phosphorylate type I receptors within a juxtamembrane cytoplasmic glycine- and serine-rich region called the GS domain and this phosphorylation event activates the type I receptor kinase to initiate downstream signaling.
[0000] Regulation of Activin and TGF-b Receptor Access
[0012] Activins are secreted in their processed, biologically active form. However, the ability of activins to access and assemble signaling receptors can be inhibited in several distinct ways. Inhibins (a-b) share a b subunit with activins and are TGF-b superfamily members that act in conjunction with the membrane proteoglycan betaglycan to form high affinity complexes with activin type II receptors, thereby preventing these receptors from binding activin and initiating signaling. The soluble, extracellular activin binding follistatins bind activins with high-affinity and also block the ability of activin to bind its cell-surface receptors and initiate signaling. In addition, the pseudo (decoy) type I receptor BAMBI (BMP and Activin Membrane-Bound Inhibitor) can bind BMP or activin in non-functional complexes with activin and BMP receptors to block signaling.
[0013] Unlike activin, TGF-b isoforms are not secreted in an active form but rather are secreted as inactive “latent” complexes. These complexes comprise the inactive TGF-b dimer in non-covalent complexes with two prosegments to which one of several “latent TGF-b binding proteins” is often linked. Latent TGF-b complexes and their binding proteins associate with the extracellular matrix and await one of several possible activating stimuli to provide a rapidly available pool of releasable TGF-b that can respond to highly localized signals.
[0000] Smad Signaling
[0014] Based upon genetic studies in Drosophila and Caenorhabditis elegans , a group of proteins now called Smads have been found to transduce signals from receptor serine kinases and mediate regulation of target gene transcription by activin, TGF-b and other TGF-b superfamily members. Structural and functional considerations allow subdivision of Smads into three subfamilies: pathway-specific, common mediator, and inhibitory Smads.
[0015] Ligand/receptor assembly and activin receptor-like kinase (ALK) phosphorylation triggers a transient ALK/pathway-specific Smad association during which the ALK phosphorylates the Smad on its last two serine residues in the C terminal SSXS motif. Activin and TGF-b signals are mediated by the pathway-specific Smads, Smad2 and Smad3 and these Smads are sequestered near their signaling receptors by Smad Anchor for Receptor Activation (SARA), a cytoplasmic membrane-associated protein that has been shown to facilitate Smad2/3 signaling.
[0016] Once activated, Smad2 and Smad3 form hetero-oligomeric complexes with the common mediator Smad, Smad4, that was first discovered in humans as the pancreatic tumor suppressor gene, DPC4. Smad2/3/4 complexes translocate to the nucleus and interact directly with DNA and/or with cell-type specific co-activator or co-repressor proteins leading to the activation or repression of target genes.
[0017] Two vertebrate inhibitory Smads have been identified, Smad6 and 7, which lack the C-terminal SSXS motif found in the pathway specific Smads. Smad6 and 7 are inhibitors of Smad signaling and bind to activin receptor-like kinases (ALKs) to prevent phosphorylation and activation of the pathway-specific Smads. In transfected cells, Smad7 inhibits transcriptional responses induced by activin or TFG-b or by a constitutively active ALK4. Smad7 may therefore provide an intracellular feedback signal to restrain the effects of activin and TFG-b.
[0000] Smad2/3 Signaling and Growth Control
[0018] TGF-b and activin are both well known for their ability to inhibit proliferation of multiple cell types including most epithelial cells, and gene expression profiling has indicated essential similarity of transcriptional responses to constitutively active activin or TGF-b type I receptors in cancer cells. Activation of the Smad2/3 signaling pathway leads to inhibition of cell cycle progression during G1 and in some cases terminal differentiation, or apoptosis. The growth inhibitory response to Smad2/3 signals has been divided into two major classes: gene responses that lead to inhibition of cyclin-dependent kinases (cdks) and down regulation of c-myc.
[0019] The retinoblastoma tumor suppressor protein (pRb) and its family members p107 and p130 control cell cycle progression and have activity that is regulated by cdk phosphorylation. TGF-b signals have been shown to induce cdk inhibitors including p15 INK4B (p15) and p21 CIP1/WAF1 (p21) and to down regulate the tyrosine phosphatase cdc25A. p15 binds and inactivates cdk4 and cdk6 causing displacement of p27 from cyclin D-cdk4/6, allowing it to bind and inhibit cyclin E-cdk2. p21 also binds and inhibits cyclin E-cdk2. cdc25A is an activator of cyclin D-cdk4 and its down regulation therefore reduces the activity of this cdk. Overall, decreased cdk activity in response to Smad2/3 signaling reduces pRb phosphorylation by these cdks, allowing pRb to prevent E2F function and block cell cycle progression.
[0020] Unlike cdk inhibition, which exhibits cell type dependent diversity, down regulation of c-Myc, a member of the basic helix-loop-helix leucine zipper (bHLH-LZ) family of transcription factors, is observed in most cell types that are growth inhibited by Smad2/3 signals. In addition, down regulation of c-Myc by Smad signals is required for the inactivation of cdks, and evidence also implicates c-Myc as a positive regulator of cdc25A expression. It was recently shown that E2F4/5 proteins and the Rb protein p107 form a pre-formed complex with Smad3 in the cytoplasm that awaits TGF-b receptor activation, Smad3 phosphorylation and Smad4 assembly leading to translocation of the complex to the nucleus to bind the c-myc promoter and repression of the c-myc gene.
[0021] The Id family of transcriptional regulators inhibit terminal differentiation, promote cell proliferation and have been implicated in cancer. Myc and Id proteins can form complexes that cooperate to override the tumor suppressor function of pRb. Interestingly, it was recently shown that TGF-b causes repression of Id gene expression via preassembled, cytoplasmic Smad3-ATF3 complexes that translocate to the nucleus with Smad4 and target Id promoters following TGF-b receptor activation. It was also recently demonstrated that key cellular responses to TGF-b signals, including induction of the cdk inhibitor p21, rely on direct interactions between Smad2 and the tumor suppressor and transcriptional regulator p53. In summary, these results indicate that Smad2 and Smad3 likely play essential but distinct roles in regulating cell proliferation.
[0000] Smad2/3 Pathway and Cancer
[0022] It is not surprising that disruptions or alterations in the activin and TGF-b signaling pathways have been observed in several types of human cancer. Inactivating mutations in TbRII have been observed in colorectal and gastric carcinomas and inactivation of ActRII was recently observed in gastrointestinal cancers. An inactivating mutation in TbRI (ALK5) occurs in one third of ovarian cancers observed and ALK4 mutations have been described in pancreatic cancer leading to the designation of ALK4 as a tumor suppressor gene.
[0023] The activin/TGF-b signaling pathway is also disrupted by mutations in Smad4 and Smad2. As mentioned above, Smad4 was originally identified as DPC4 (deleted in pancreatic carcinoma locus 4) and this gene is functionally absent in half of all pancreatic cancers and one third of colon carcinomas. Smad2 is also inactivated in a small proportion of colorectal cancers and lung cancers. Although Smad3 mutations have not yet been observed in human cancers, Smad3 −/− mice developed colorectal cancer.
[0024] Interestingly, despite its antiproliferative effects, Smad2/3 signaling can also exacerbate the cancer phenotype under conditions in which cells have become refractory to Smad2/3-induced growth inhibition. For example, increased production of TGF-b or activin by tumor cells that are no longer growth inhibited by Smad2/3 signals may lead to increased angiogenesis, decreased immune surveillance and/or an increase in the epithelial to mesenchymal transition (EMT) of tumor cells. Collectively, these effects can lead to increased tumor growth and metastasis.
[0000] Epidermal Growth Factor-Cripto, FRL-1, Cryptic (EGF-CFC) Protein Family
[0025] Similar to activin, members of the nodal family and GDF-1/Vg1 have been shown to signal via the activin receptors ActRII/IIB and ALK4. Unlike activin, however, these TGF-b superfamily members require additional co-receptors from the Epidermal Growth Factor-Cripto, FRL-1, Cryptic (EGF-CFC) protein family to assemble type II and type I receptors and generate signals.
[0026] The EGF-CFC family consists of small, glycosylated, extracellular signaling proteins including human and mouse Cripto and Cryptic, Xenopus FRL-1 and zebrafish one-eyed pinhead (oep). EGF-CFC proteins are known to act as anchored cell surface co-receptors but they also have activity when expressed as soluble proteins or when they are secreted from the cell surface following enzymatic cleavage of their GPI anchor. Genetic studies in zebrafish and mice have shown that EGF-CFC proteins are required for mesoderm and endoderm formation, cardiogenesis, and the establishment of left/right asymmetry during embryonic development. Cripto knockout mouse embryos lack a primitive streak and fail to form embryonic mesoderm. This phenotype is very similar to that observed in ActRIIA −/− ; ActRIIB −/− mice, ALK4 −/− mice and Nodal −/− mice, consistent with a requirement for nodal signaling via activin receptors and a role for Cripto to initiate primitive streak elongation and mesoderm formation.
[0027] It has been shown that Cripto independently binds nodal via its EGF-like domain and ALK4 via its CFC domain. Furthermore, selected point mutations in Cripto that block nodal binding or ALK4 binding disrupt nodal signaling. Substantial biochemical evidence indicates that nodal and Vg1/GDF1 form a complex with activin receptors only in the presence of EGF-CFC proteins.
[0000] Cripto is a Tumor Growth Factor
[0028] Cripto is an EGF-CFC protein that was first isolated as a putative oncogene from a human teratocarcinoma cell line and it was subsequently shown to be able to confer anchorage independent growth to NOG-8 mouse mammary epithelial cells. Cripto is expressed at high levels in human breast, colon, stomach, pancreas, lung, ovary, endometrial, testis, bladder and prostate tumors while being absent or expressed at low levels in their normal counterparts. The elucidation of the signals and transcriptional events underlying the high level of Cripto expression in these tumors remains an important area of future research.
[0029] With regard to Cripto's mechanism(s) of mitogenic action, it has been shown that recombinant, soluble Cripto and a synthetic 47 amino acid Cripto fragment spanning the EGF-like domain can activate both the mitogen activated protein kinase (MAPK) pathway and the phosphatidylinositol-3-kinase (PI3K) pathway. Treatment of HC-11 mammary epithelial cells with soluble Cripto or the 47-mer peptide resulted in tyrosine phosphorylation of the SH2-adaptor protein Shc, association of Shc with Grb2 and activation of the p42/44 Erk/MAPK pathway. It was also shown that soluble Cripto caused phosphorylation of the p85 regulatory subunit of PI3K leading to phosphorylation and activation of AKT in SiHa cervical carcinoma cells. Cripto does not bind to members of the EGF receptor family, although [ 125 I]-Cripto specifically labeled breast cancer cell lines and formed crosslinked complexes with 60 kDa and 130 kDa membrane proteins. Although these proteins were not identified, the 60 kDa protein may have been ALK4.
[0030] It was recently shown that the cytoplasmic tyrosine kinase c-Src can be activated by soluble Cripto and that its activity is required for activation of the MAPK/PI3K pathways by Cripto. The GPI-anchored proteoglycan glypican was also reported to be important in facilitating these Cripto signals and glypican was also shown to bind Cripto in a manner dependent on glycanation of glypican. The ability of Cripto to activate the MAPK and PI3K pathways, which are frequently growth-stimulatory in nature, has generally been proposed to explain Cripto's oncogenic effects.
[0000] Smad Signaling, Cripto and Cancer
[0031] The first demonstration of a physiologic role for TGF-b was its potent and reversible inhibition of developing mouse mammary gland in situ. TGF-b is now well established as an important inhibitor of mammary ductal growth and branching in vivo and over 90% of mammary carcinomas are ductal in nature. Loss of TbRII has been associated with increased risk of invasive breast cancer in women. Consistent with a role in regulating mammary ductal growth, TGF-b 1 heterozygous null mice display accelerated mammary epithelial proliferation and ductal outgrowth. Furthermore, transgenic expression of a dominant negative TbRII construct in mammary gland diminishes responsiveness to TGF-b and caused increased incidence of tumors in response to carcinogen relative to control mice. Conversely, transgenic overexpression of TGF-b 1 in mammary gland protects against chemical-induced tumors. These results provide direct evidence that TGF-b signaling can actively prevent tumorigenesis in mouse mammary gland. There is also evidence that activin inhibits proliferation of both primary and transformed mammary epithelial cells. Together, these results indicate the importance of the Smad2/3 pathway in inhibiting mammary epithelial cell proliferation and tumorigenesis.
[0032] Cripto is overexpressed in many types of human tumors, including ˜80% of breast carcinomas, while its expression is low or absent in their normal counterparts. In contrast to TGF-b, Cripto promotes growth in mammary cells and Cripto overexpression transforms mouse NOG-8 and CID-9 mammary epithelial cells. Cripto overexpression in these cell lines enabled them to grow in soft agar and each displayed an enhanced proliferation rate in monolayer culture. These cells were, however, unable to form tumors in nude mice.
[0033] It was also shown that targeted disruption of endogenous Cripto in CID-9 cells via a retroviral antisense construct led to a decreased rate of cellular proliferation. Both the soluble Cripto protein and the 47 amino acid EGF-like domain Cripto peptide have also been shown to facilitate ductal branching and cause mammary ductal hyperplasia. As discussed above, these effects have been explained as the result of the ability of Cripto to activate mitogenic signaling pathways including the MAPK and PI3K pathways. However, many of the growth-related effects of Cripto are also generally consistent with antagonism of the Smad2/3 pathway.
[0034] The prior art is lacking in evidence on whether Cripto can play a dual role as an oncogene, not only acts by activating mitogenic MAPK/PI3K pathways, but also antagonizes the antiproliferative Smad2/3 pathway. The present invention thus studies the oncogenic mechanism of Cripto protein in order to gain insight into its effects on activin/TGF-b signaling.
SUMMARY OF THE INVENTION
[0035] TGF-b and activin regulate tissue homeostasis by activating the Smad2/3 intracellular signaling pathway leading to potent inhibition of proliferation of multiple cell types including epithelial cells. Disruption of this signaling pathway is associated with oncogenesis and tumorigenesis. Cripto is a developmental oncoprotein that is highly expressed in human tumors but not their normal tissue counterparts. Overexpression of Cripto transforms mammary epithelial cells in vitro. The present invention shows that Cripto can antagonize activin and TGF-b signaling. These results suggest that Cripto may be generally capable of blocking antiproliferative Smad2/3 signals and provides a novel mechanism of oncogenic action with multiple therapeutic implications.
[0036] Based on the data presented below, a model for the mechanism of Cripto regulation of activin and TGF-b signaling is proposed ( FIG. 13 ). In the absence of Cripto, activin and TGF-b signal by binding their respective type II receptors and then recruiting their type I receptors (ALK4 and ALK5). Activin and TGF-b type II receptors phosphorylate the GS domain of ALK4 and ALK5, thereby activating the type I kinase and initiating downstream signaling. Cripto antagonizes activin and TGF-b signaling by forming a complex with activin and TGF-b and their type II receptors. This complex precludes the formation of a functional activin/TGF-b.type II.type I complex and therefore blocks signaling.
[0037] In one embodiment of the present invention, there is provided a method of augmenting signaling of a ligand of receptor serine kinase in a cell. The method involves inhibiting the formation of complexes between Cripto and a ligand of receptor serine kinase on the surface of a cell.
[0038] In another embodiment, there is provided a method of using a mutant of a ligand of receptor serine kinase to augment Smad2/3 signaling in a cell.
[0039] The present invention also provides a method of using a Cripto mutant that lacks the EGF domain to selectively antagonize activin-B signaling.
[0040] In another embodiment, there is provided a method of inhibiting signaling of a ligand of receptor serine kinase in a cell. The method involves enhancing the formation of complexes between Cripto and a ligand of receptor serine kinase on the surface of a cell.
[0041] Other and further aspects, features, and advantages of the present invention will be apparent from the following description of the presently preferred embodiments of the invention. These embodiments are given for the purpose of disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIG. 1 shows a model indicating the proposed dual oncogenic mechanisms of Cripto. Cripto activates mitogenic MAPK and PI3K pathways by binding an as-yet uncharacterized transmembrane receptor leading to activation of c-Src. It is proposed that Cripto also blocks Smad2/3 signaling by competitively antagonizing functional recruitment of type I activin and TGF-b receptors to ligand.type II receptor complexes.
[0043] FIG. 2 shows Cripto binds activin in the presence of ActRII and competes with ALK4 for activin.ActRII binding. 293T cells were transfected with the indicated constructs and subjected to crosslinking with [ 125 I]-activin-A as previously described (Gray et al., 2003). The cells were solubilized and crosslinked complexes were isolated by immunoprecipitation using the indicated antibodies. Immunoprecipitated proteins were resolved by SDS-PAGE and visualized by autoradiography as previously described (Gray et al., 2003).
[0044] FIG. 3 shows Cripto binds TGF-b 1 in the presence of TbRII and competes with ALK5 for TGF-b 1 .TbRII binding. 293T cells were transfected with the indicated constructs and subjected to crosslinking with [ 125 I]-TGF-b 1 as previously described (Gray et al., 2003). The cells were solubilized and crosslinked complexes were isolated by immunoprecipitation using the indicated antibodies. Immunoprecipitated proteins were resolved by SDS-PAGE and visualized by autoradiography as previously described (Gray et al., 2003).
[0045] FIG. 4 shows Cripto blocks activin-A and TGF-b 1 signaling in HepG2 cells. HepG2 cells were transfected with either empty vector or Cripto as previously described (Gray et al., 2003) and then treated with the indicated doses of either activin-A ( FIG. 4A ) or TGF-b 1 ( FIG. 4B ). Luciferase activities were normalized relative to b-galactosidase activities and data were presented as fold increases in luciferase activity relative to untreated cells.
[0046] FIGS. 5 A-B show expression of Cripto mutants at the cell surface of 293T cells. FIG. 5A is a diagram of mouse Cripto indicating the positions of the signal peptide, N-terminal FLAG epitope, EGF-like domain, CFC domain and the C-terminal site of GPI-anchor attachment. In addition, the site of fucosylation (threonine 72) and the positions of the tryptophan residues that are substituted with glycine residues in the mCFC mutant (W104G, W107G) are indicated. (B) Empty vector or the indicated Cripto constructs were transfected in triplicate into 293T cells and the resulting cell surface expression of these constructs in intact cells was measured using anti-FLAG antibody in an ELISA-based assay ( FIG. 5B ).
[0047] FIG. 6 shows the EGF-like domain of Cripto mediates antagonism of TGF-b signaling. 293T cells were transfected in triplicate with vector or the indicated Cripto constructs and A3-luciferase/FAST-2/CMV-b-galactosidase. Cells were treated with vehicle or with 100 pM TGF-b 1 and resulting luciferase activities were normalized relative to b-gal activities. Data were presented as fold increase in luciferase activities in TGF-b 1 treated cells relative to vehicle treated cells.
[0048] FIG. 7 shows the EGF-like domain of Cripto is required for antagonism of activin-A and TGF-b 1 signaling in 293T cells. 293T cells were transfected with the indicated constructs and then treated with vehicle or 1 nM activin-A or 0.3 nM TGF-b 1 . Luciferase activities were normalized to b-galactosidase activities and data were presented as fold increase in luciferase activities relative to untreated cells.
[0049] FIGS. 8 A-B show the CFC domain of Cripto is not required for binding to TGF-b. 293T cells were transfected with the indicated constructs and subjected to crosslinking with [ 125 I]-TGF-b 1 . Solubilized, crosslinked complexes were isolated by immunoprecipitation using anti-His antibody targeting TbRII ( FIG. 8A ) or anti-FLAG antibody targeting Cripto ( FIG. 8B ). Immunoprecipitated proteins were resolved by SDS-PAGE and visualized by autoradiography.
[0050] FIGS. 9 A-C show Cripto T72A mutation disrupted the ability to block TGF-b and activin signaling. 293T cells were transfected in triplicate with vector, Cripto or Cripto mutant (T72A) and A3-luciferase/FAST-2/CMV-b-galactosidase. Cells were treated with vehicle or with 100 pM TGF-b 1 ( FIG. 9A ), 300 pM activin-A ( FIG. 9B ) or 300 pM activin-B ( FIG. 9C ) and resulting luciferase activities were normalized and presented as fold increase relative to b-galactosidase activities in vehicle-treated cells.
[0051] FIG. 10 shows the EGF-like and CFC domains of Cripto can independently mediate antagonism of activin-B signaling. 293T cells were transfected in triplicate with vector, Cripto DEGF or Cripto DCFC in addition to A3-luciferase/FAST-2/CMV-b-galactosidase. Cells were treated with vehicle or with either 300 pM activin-A or 300 pM activin-B as indicated, and resulting luciferase activities were normalized and presented as the fold-increase relative to b-galactosidase activities in vehicle-treated cells.
[0052] FIGS. 11 A-B show Cripto DCFC mutant binds activin-A. 293T cells were transfected with the indicated constructs and subjected to crosslinking with [ 125 I]-activin-A. Solubilized, crosslinked complexes were isolated by immunoprecipitation using anti-myc antibody targeting ActRII ( FIG. 11A ) or anti-FLAG antibody targeting Cripto ( FIG. 11B ). Immunoprecipitated proteins were resolved by SDS-PAGE and visualized by autoradiography.
[0053] FIG. 12 shows Cripto antagonizes activin/TGF-b but facilitates nodal signaling in 293T cells. 293T cells were transfected with either empty vector or nodal and the indicated amount of Cripto DNA as previously described (Gray et al., 2003) and then treated as indicated with 1 nM activin-A or 0.3 nM TGF-b 1 . Luciferase values were normalized to b-galactosidase activities and data were presented as fold increase in luciferase activities relative to untreated cells.
[0054] FIGS. 13 A-B depict proposed mechanisms of Cripto regulation of TGF-b ligand signaling. The model illustrates the ability of Cripto to either facilitate ( FIG. 13A ) or inhibit ( FIG. 13B ) signaling of TGF-b superfamily members. Cripto and related Epidermal Growth Factor-Cripto, FRL-1, Cryptic (EGF-CFC) protein family proteins bind directly to nodal or Vg1/GDF1, allowing these ligands to assemble type II and type I signaling receptors and initiating responses including mesoderm induction ( FIG. 13A ). Conversely, by binding TGF-b and activin while these ligands are in complex with their respective type II receptors, Cripto disrupts functional recruitment of type I receptors and inhibits signaling responses such as growth inhibition ( FIG. 13B ).
[0055] FIG. 14 depict diagrams of Cripto and Cripto mutant constructs. The domain structure of wild type mouse Cripto is indicated showing attachment to membrane via C-terminal GPI anchorage. Position of incorporated epitope tags and sites of deletions and selected mutations are indicated.
[0056] FIG. 15 shows alignment of Epidermal Growth Factor-Cripto, FRL-1, Cryptic (EGF-CFC) proteins. Mouse Cripto was aligned with other members of the EGF-CFC family including human Cripto, mouse Cryptic, human Cryptic, Xenopus FRL-1 and zebrafish one-eyed pinhead (oep) using the CLUSTAL algorithm of the MEGALIGN program (DNASTAR). The EGF-like domain is boxed and shaded red, the CFC domain is boxed and shaded blue, and conserved cysteines within these domains are shaded yellow. Disulfide arrangement of the EGF-like domain is indicated. The signal peptide of mouse Cripto is indicated with red lettering, the hydrophobic C-terminal domain is indicated with purple lettering and the fucosylated threonine is shaded white. Conserved residues targeted for mutagenesis are indicated by asterisks and the EGF1, EGF2 and mCFC mutations are indicated by red asterisks.
DETAILED DESCRIPTION OF THE INVENTION
[0057] The present invention provides methods of augmenting signaling induced by a ligand of receptor serine kinase in a cell by inhibiting the formation of complexes between Cripto and the receptor serine kinase ligand on the surface of the cell. Ligands of receptor serine kinase include, but are not limited to, activin and TGF-b, whereas examples of receptor serine kinase include type I activin receptor-like kinases-4 (ALK-4) or activin receptor-like kinases-5 (ALK-5). In general, the cells are derived from breast, colon, stomach, pancreas, lung, ovary, endometrial, testis, bladder or prostate. Augmentation of signaling mediated by receptor serine kinase would increase phosphorylation and activation of Smad2 and Smad3, resulting in decreased cellular proliferation.
[0058] In one embodiment, formation of complexes between Cripto and ligand of receptor serine kinase is inhibited by an anti-Cripto antibody directed against an epitope of Cripto. For example, the anti-Cripto antibody is directed against an epitope in the EGF-like domain of Cripto. Alternatively, formation of complexes between Cripto and receptor serine kinase ligand can be inhibited by a soluble receptor serine kinase extracellular domain that binds Cripto but not ligand of receptor serine kinase. In one embodiment, the soluble extracellular domain is an activin receptor-like kinases-4 (ALK-4) extracellular domain. Preferably, the ALK-4 extracellular domain comprises a mutation at one or more positions such as amino acid position 70, 75 and/or 77. For example, the ALK-4 extracellular domain comprises an alanine at amino acid position 70, 75 and/or 77.
[0059] In another embodiment, formation of complexes between Cripto and ligand of receptor serine kinase is inhibited by inhibiting the expression of Cripto in the cell. Cripto expression can be inhibited by antisense transcript of Cripto, small inhibitory RNA (siRNA) directed against Cripto or by mutating at least one allele of Cripto by homologous recombination.
[0060] In yet another embodiment, there is provided a method of using a mutant of a ligand of receptor serine kinase to augment Smad2/3 signaling in a cell. The mutant ligand retains signaling activity but is unable to bind to Cripto, thereby bypassing antagonism by Cripto. In general, ligands of receptor serine kinase include, but are not limited to, activin and TGF-b.
[0061] The present invention also provides a method of using a Cripto mutant that lacks the EGF domain to selectively antagonize activin-B signaling. In general, the Cripto mutant can be soluble or cell surface-bound. Results disclosed herein show that the EGF-like domain of Cripto is required to antagonize activin-A, activin-B and TGF-b while the CFC domain is sufficient to block activin-B but not activin-A or TGF-b. Therefore Cripto mutant that lacks the EGF domain will be a useful research tool to distinguish the relative importance of activin-A as opposed to activin-B signaling in various biological contexts. For example, it has also been previously demonstrated that release of FSH from rat anterior pituitary gonadotropes is mediated by activin-B. Therefore, a Cripto mutant such as DEGF is predicted to block FSH release without affecting activin-A or TGF-b signaling. By blocking FSH release, spermatogenesis will be disrupted potentially causing reversible infertility. Therefore, cell attached or soluble Cripto constructs in which the EGF-like domain has been deleted may have utility as male contraceptives.
[0062] The present invention further provides a method of inhibiting signaling induced by a ligand of receptor serine kinase in a cell by enhancing the formation of complexes between Cripto and the receptor serine kinase ligand on the surface of the cell. Ligands of receptor serine kinase include, but are not limited to, activin and TGF-b, whereas examples of receptor serine kinase include type I activin receptor-like kinases-4 (ALK-4) or activin receptor-like kinases-5 (ALK-5). In general, the cells are derived from breast, colon, stomach, pancreas, lung, ovary, endometrial, testis, bladder or prostate. In one embodiment, formation of complexes between Cripto and ligand of receptor serine kinase is enhanced by increasing the expression of Cripto in the cell. For example, Cripto expression can be increased by administering to the cell viral or plasmid vectors that encodes Cripto protein. Alternatively, formation of complexes between Cripto and receptor serine kinase ligand can be enhanced by administering soluble Cripto or cell surface-bound Cripto to the cell.
[0063] The following examples are given for the purpose of illustrating various embodiments of the invention and are not meant to limit the present invention in any fashion. The present examples, along with the methods, procedures, treatments, molecules, and specific compounds described herein are presently representative of preferred embodiments. One skilled in the art will appreciate readily that the present invention is well adapted to carry out the objects and obtain the ends and advantages mentioned, as well as those objects, ends and advantages inherent herein. Changes therein and other uses which are encompassed within the spirit of the invention as defined by the scope of the claims will occur to those skilled in the art.
EXAMPLE 1
[0000] Cripto Binds Activin in the Presence of ActRII and Competes with ALK4 for Activin.ActRII Binding
[0064] The ability of [ 125 I]-activin-A to form crosslinked complexes with Cripto was tested in the presence or absence of activin receptors. FIG. 2 shows that when 293T cells were transfected with ActRII ( FIG. 2A , lane 2) and then subjected to labeling and crosslinking with [ 125 I]-activin-A followed by immunoprecipitation with an antibody directed against ActRII, an activin.ActRII crosslinked complex of ˜80 kDa was evident consistent with previous crosslinking results. The appearance of two ActRII.activin bands is routinely observed and is likely the result of differential glycosylation of ActRII.
[0065] Co-transfection of ActRII with ALK4 ( FIG. 2A , lane 5) results in crosslinking of [ 125 I]-activin-A to both receptor types as indicated by the appearance of the activin.ALK4 crosslinked complex at ˜60 kDa. No binding of [ 125 I]-activin-A to Cripto was detected in the absence of activin type II receptors ( FIG. 2C , lane 2). However, when ActRII was co-transfected with Cripto, activin-crosslinked complexes of ˜32, 45 and 52 kDa were observed ( FIG. 2A , lane 6). These complexes were not present in samples in which Cripto was not transfected (lanes 1-3, 5; the ˜28 kDa band represents crosslinked [ 125 I]-activin-A dimer). The Cripto species of ˜18, 31 and 38 kDa (the activin bA monomer is ˜14 kDa and the gels were run under reducing conditions) likely have differential glycosylation and/or other modifications.
[0066] The presence of [ 125 I]-activin-A.Cripto bands indicates the formation of stable activin.ActRII.Cripto complexes since an antibody directed against ActRII was used in the immunoprecipitation. Activin.ActRII and activin.Cripto crosslinked bands were also evident when 293T cells were co-transfected with ActRII and Cripto and then subjected to immunoprecipitation using an antibody directed against Cripto ( FIG. 2C , lanes 3 and 5).
[0067] The effects of co-transfecting 293T cells with Cripto, ActRII and ALK4 were further tested. When Cripto was transfected with ActRII and ALK4 ( FIG. 2A , lane 8), [ 125 I]-activin-A formed a crosslinked complex with ActRII and Cripto, while crosslinking to ALK4 was greatly decreased relative to crosslinking in the absence of Cripto ( FIG. 2A , compare lane 5 and lane 8). Co-transfection with Cripto did not decrease expression of ALK4 as shown by Western blot (data not shown).
[0068] The effects of Cripto on activin.ActRII.ALK4 complex formation as assessed following immunoprecipitation with an antibody directed against ALK4. FIG. 2B shows that when 293T cells were transfected with vector ( FIG. 2B , lane 1), ActRII ( FIG. 2B , lane 2), ALK4 ( FIG. 2B , lane 3), Cripto ( FIG. 2B , lane 4) or co-transfected with ActRII and Cripto ( FIG. 2B , lane 6) or ALK4 and Cripto ( FIG. 2B , lane 7) and then subjected to crosslinking with [ 125 I]-activin-A, an ALK4 antibody failed to isolate labeled complexes. This is consistent with the inability of either Cripto or ALK4 to bind [ 125 I]-activin-A in the absence of type II receptors. When ActRII and ALK4 were co-expressed, the anti-ALK4 antibody precipitated a complex in which both ActRII and ALK4 were labeled ( FIG. 2B , lane 5).
[0069] Co-transfection of Cripto with ActRII and ALK4 substantially blocked the appearance of these bands ( FIG. 2B , lane 8), consistent with its ability to block crosslinking of activin to ALK4 and the association of ALK4 with ActRII. However, when ActRII, ALK4 and Cripto were co-transfected and cells were labeled with [125I]-activin-A, the ALK4 antibody could precipitate labeled [ 125 I]-activin-A.Cripto complexes ( FIG. 2B , lane 8).
[0070] Cripto blocks labeling and crosslinking of [ 125 I]-activin-A to ALK4 in a dose dependent manner. FIG. 2D shows that as the amount of transfected Cripto DNA is increased, the ability of [ 125 I]-activin-A to crosslink to ALK4 decreases. These results provide a mechanism for competitive antagonism of activin signaling by Cripto.
EXAMPLE 2
[0000] Cripto Binds TGF-b 1 in the Presence of TbRII and Competes with ALK5 for TGF-b 1 .TbRII Binding
[0071] Similar to activin-A, TGF-b1 binds Cripto in the presence of its type II receptor TbRII. FIG. 3A shows crosslinking of [ 125 I]-TGF-b 1 to 293T cells transfected with TbRII and the indicated amounts of Cripto DNA. A prominent [ 125 I]-TGF-b 1 .Cripto crosslinked band of ˜32 kDa appeared and increased in intensity as the amount of Cripto DNA transfected was increased. Fainter species of ˜40 kDa were also visible ( FIG. 3A ).
[0072] The effects of Cripto on the ability of [ 125 I]-TGF-b 1 to crosslink to its type I receptor ALK5 were examined. FIG. 3B shows that [ 125 I]-TGF-b 1 forms a crosslinked complex with its type II receptor of 85 kDa ( FIG. 3B , lane 2) and that co-transfection of Cripto with TbRII results in the [ 125 I]-TGF-b 1 .TbRII complex as well as the [ 125 I]-TGF-b 1 .Cripto complex. When TbRII and ALK5 were co-transfected, [ 125 I]-TGF-b 1 labeled both receptors to yield complexes of ˜85 kDa and 60 kDa respectively ( FIG. 3B , lane 4). When TbRII, ALK5 and Cripto were co-transfected, all three bands were evident ( FIG. 3B , lane 5). However, the intensity of the ALK5 band was reduced, indicating Cripto may compete with ALK5 for available TGF-b.TbRII binding sites.
EXAMPLE 3
[0000] Cripto Blocks Activin-A and TGF-b 1 Signaling in HepG2 Cells
[0073] HepG2 cells do not express Cripto and require transfected Cripto to respond to nodal signals. Therefore, the effects of transfected Cripto on activin-A and TGF-b 1 signaling were tested in this cell line. Cripto and the activin/TGF-b responsive luciferase reporter construct 3TP-lux were transfected into HepG2 cells and the effect of Cripto on activin-A and TGF-b 1 -induced luciferase expression was measured. As shown in FIG. 4 , activin-A and TGF-b 1 caused dose-dependent increases in luciferase expression that were inhibited by Cripto. At maximal doses of these ligands there was an approximately four-fold reduction in signaling ( FIG. 4A , B). As a control, the effect of Cripto on the ability of the activin-A paralog BMP7 to induce luciferase expression using the BMP-selective reporter BRE-luc has previously been tested. Although BMP7 induced luciferase expression in HepG2 cells in a dose-dependent manner, Cripto did not affect this induction, indicating that Cripto's effects may be selective for activin, TGF-b and the Smad2/3 pathway (Gray et al., 2003).
EXAMPLE 4
[0000] Expression of Cripto Mutants at the Cell Surface of 293T Cells
[0074] The domain structure of mouse Cripto is illustrated in FIG. 5A . This diagram indicates the locations of the signal peptide, the EGF-like domain, the CFC domain and the C-terminal hydrophobic region required for GPI-anchor attachment. In addition, the positions of the FLAG epitope, the fucosylated threonine residue (Thr 72), and the mCFC mutations (H104G, W107G) (Yeo and Whitman, 2001) are shown.
[0075] Five Cripto constructs were evaluated in this study: wild type Cripto; Cripto (T72A), which is unable to be fucosylated and does not facilitate nodal signaling; Cripto DEGF, in which the EGF-like domain has been deleted; Cripto mCFC, which does not facilitate nodal signaling and has two mutations in the CFC domain that block ALK4 binding (H104G, W107G); and Cripto DCFC, in which the CFC domain has been deleted.
[0076] Cell surface expression levels of wild type Cripto and these four Cripto mutants are shown in FIG. 5B . 293T cells were transfected with the indicated Cripto constructs and cell surface expression was subsequently measured using anti-FLAG antibody in an intact cell ELISA-based assay that we have previously used to measure expression levels of cell surface proteins (Harrison et al., 2003). Briefly, 293T cells were plated on 24 well polylysine-coated plates at a density of 100,000 cells per well, transfected 24 h later with 0.5 mg vector or Cripto DNA per well and then assayed for cell surface expression 48 h after transfection. Cells were rinsed in Hepes Dissociation Buffer (HDB) (12.5 mM Hepes (pH 7.4), 140 mM NaCl and 5 mM Kcl), fixed in 4% paraformaldehyde for 30 min at 4° C., rinsed with HDB and then incubated in HDB with 3% bovine serum albumin (BSA) for 30 min at room temperature (RT). Cells were then incubated for 2 h with 2 μg/ml anti-Myc antibody in HDB with 3% BSA, rinsed with HDB, and incubated with peroxidase-conjugated anti-mouse IgG in HDB with 3% BSA for 1 h at room temperature. Wells were rinsed with HDB and then 100 μl of TMB peroxidase substrate was added to each well. Plates were incubated at RT until the solutions turned visibly blue. Peroxidase activity was stopped by adding 100 μl of 0.18 M H 2 SO 4 to each well and peroxidase activity was quantified by measuring the absorbance of the resulting yellow solutions at 450 nm.
[0077] As shown in FIG. 5B , these Cripto constructs were expressed at cell surface at similar levels.
EXAMPLE 5
[0000] The EGF-Like Domain of Cripto is Required for Antagonism of Activin-A and TGF-b Signaling
[0078] Like other Epidermal Growth Factor-Cripto, FRL-1, Cryptic (EGF-CFC) protein family members, Cripto has two conserved cysteine-rich domains, an N-terminal EGF-like domain and a C-terminal CFC domain. Each of these modular domains can have activity in the absence of the other and both have been implicated in specific protein-protein interactions and signaling functions. To determine the roles of the Cripto EGF-like and CFC domains in blocking TGF-b signaling, we compared the ability of wild type Cripto to inhibit TGF-b with that of Cripto mutants in which either the EGF-like or CFC domain was mutated or deleted.
[0079] Luciferase assays were carried out essentially as previously described (Gray et al., 2003). HepG2 cells were plated at 150,000 cells per well in 24-well plates and transfected in triplicate approximately 24 h later with 1 mg DNA per well with a ratio of 800 ng Cripto/100 ng 3TP-lux/100 ng cytomegalovirus (CMV)-b-galactosidase (CMV-b-galactosidase). Cells were treated with TGF-b 1 approximately 30 h after transfection and harvested 16 h following treatment. Cells were incubated in solubilization buffer (1% Triton X-100, 25 mM glycylglycine (pH 7.8), 15 mM MgSO 4 , 4 mM EGTA and 1 mM DTT) for 30 min on ice and luciferase reporter activity was measured and normalized relative to CMV-b-gal activities. 293T cells were plated on 24-well plates treated with polylysine at 100,000 cells per well and transfected in triplicate approximately 24 h later with 0.5 mg DNA per well using 400 ng Cripto/50 ng FAST2 (FoxH1)/25 ng A3-lux/25 ng CMV-b-galactosidase per well. Cells were treated approximately 24 h following transfection and then harvested approximately 16 h following treatment. Luciferase assays were performed as described for HepG2 cells described above.
[0080] FIG. 6 shows that when 293T cells were transfected with empty vector or various Cripto constructs together with FAST2/A3-luciferase and then treated with 100 pM TGF-b 1 , luciferase induction was reduced ˜3-fold in cells transfected with wild-type Cripto ( FIG. 6 , lane 2) but was unaffected in cells transfected with Cripto DEGF mutant (DEGF) ( FIG. 6 , lane 3) relative to induction of luciferase in cells transfected with empty vector ( FIG. 6 , lane 1). This result indicates that the EGF-like domain of Cripto is required for antagonism of TGF-b 1 signaling. In contrast, the mCFC mutant (H104G, W107G) blocked TGF-b signaling as effectively as wild type Cripto ( FIG. 6 , lane 4) while the Cripto DCFC mutant (DCFC) blocked TGF-b signaling even more effectively than wild type Cripto ( FIG. 6 , lane 5). Therefore, the CFC domain is not required for Cripto antagonism of TGF-b signaling but rather it may partially interfere with Cripto's ability to block TGF-b signaling as indicated by the fact that Cripto DCFC had a greater blocking effect than wild type Cripto. Together, these data indicate that the EGF-like domain of Cripto is both necessary and sufficient for inhibition of TGF-b signaling.
[0081] In another experiment, activin-A treatment caused a 30 to 40-fold and TGF-b 1 treatment caused an ˜25 fold induction of luciferase expression in 293T cells which were blocked by wild type Cripto ( FIG. 7 ). The ability of Cripto to block activin-B signaling was similar to its ability to block activin-A signaling in these cells (data not shown). Like wild type Cripto, the Cripto mCFC mutant blocked activin-A and TGF-b 1 signaling in these cells ( FIG. 7 ). In contrast, neither the Cripto DEGF mutant with the EGF-like domain deleted nor the EGF1.2mCFC mutant were able to block activin-A or TGF-b 1 signaling in 293T cells ( FIG. 7 ). These results indicate that the EGF-like domain of Cripto is required for antagonism of activin-A and TGF-b signaling.
EXAMPLE 6
[0000] The CFC Domain of Cripto is not Required for TGF-b Binding
[0082] Having demonstrated that the Cripto DCFC mutant can block TGF-b 1 signaling, we next tested whether this mutant can bind and crosslink to TGF-b 1 . 293T cells were transfected with wild type Cripto ( FIG. 8 , lane 1), Cripto DCFC ( FIG. 8 , lane 2), TbRII alone ( FIG. 8 , lane 3), TbRII and Cripto ( FIG. 8 , lane 4) or TbRII and Cripto DCFC ( FIG. 8 , lane 5). Cells were labeled with [ 125 I]-TGF-b 1 and subjected to covalent crosslinking followed by immunoprecipitation with an antibody directed against TbRII (anti-His, FIG. 8A ) or against Cripto (anti-FLAG, FIG. 8B ).
[0083] For covalent crosslinking studies, 293T cells were plated on six-well plates coated with polylysine at a density of 400,000 cells per well and then transfected approximately 24 h later. Cells were transfected with 4 mg DNA per well with ratios of 0.5 mg TbRII/0.5 mg ALK5/3 mg Cripto unless otherwise indicated for [ 125 I]-TGF-b1 crosslinking or 2 mg ActRII/1 mg Cripto/1 mg vector for [ 125 I]-activin-A crosslinking. As necessary, empty vector was used to keep the amount of DNA transfected constant at 4 mg. Covalent crosslinking was performed approximately 48 h after transfection by first washing cells in Hepes Dissociation Buffer (HDB) and then incubating them with [ 125 I]-TGF-b 1 or [ 125 I]-activin-A in binding buffer (HDB containing 0.1% BSA, 5 mM MgSO 4 and 1.5 mM CaCl 2 ) at room temperature for approximately 4 h. Cells were then rinsed in HDB, incubated in HDB containing 0.5 mM disuccinylsuberate (DSS) for 30 min on ice, rinsed in HDB and then solubilized in lysis buffer (TBS containing 1% NP-40, 0.5% deoxycholate and 2 mM EDTA) for 1 h on ice. Solubilized, crosslinked complexes were incubated for approximately 24 h at 4° C. with 2 mg of either anti-FLAG (M2), anti-His or anti-myc antibodies. Immune complexes were precipitated using protein-G agarose and analyzed using SDS-PAGE and autoradiography.
[0084] As expected, anti-His antibody targeting TbRII did not precipitate labeled complexes from cells transfected with Cripto alone ( FIG. 8A , lane 1) or Cripto DCFC alone ( FIG. 8A , lane 2), but it did precipitate [ 125 I]-TGF-b 1 -labeled TbRII from cells in which TbRII was transfected either alone ( FIG. 8A , lane 3), or in which TbRII was co-transfected either with Cripto ( FIG. 8A , lane 4) or Cripto DCFC ( FIG. 8A , lane 5). In addition, a labeled Cripto complex of ˜32 kDa was immunoprecipitated from cells co-transfected with TbRII and Cripto ( FIG. 8A , lane 4) while a complex of 28 kDa was precipitated from cells co-transfected with TbRII and Cripto DCFC. The latter complex was slightly larger than [ 125 I]-TGF-b 1 dimer of 25 kDa ( FIG. 8A , lane 5) and it was consistent with the predicted size of an [ 125 I]-TGF-b 1 .DCFC complex.
[0085] We also precipitated labeled complexes with anti-FLAG antibody targeting Cripto and Cripto DCFC. When 293T cells were transfected with Cripto alone ( FIG. 8B , lane 1) or Cripto DCFC alone ( FIG. 8B , lane 2), crosslinked with [ 125 I]-TGF-b 1 and immunoprecipitated with an anti-FLAG antibody, no bands were observed. This result is consistent with the inability of Cripto and Cripto DCFC to bind TGF-b in the absence of TbRII. As predicted, transfection of TbRII alone followed by cell labeling, crosslinking and immunoprecipitation using anti-FLAG antibody did not result in observation of crosslinked complexes ( FIG. 8B , lane 3). However, co-transfection of 293T cells with TbRII and Cripto ( FIG. 8B , lane 4) or TbRII and Cripto DCFC ( FIG. 8B , lane 5) led to precipitation of complexes of ˜32 kDa and ˜28 kDa representing the [ 125 I]-TGF-b 1 .Cripto complex and the [ 125 I]-TGF-b 1 .DCFC complex, respectively. This result provided further evidence that the CFC domain is not required for Cripto binding to TGF-b. In addition, a ˜85 kDa band representing [ 125 I]-TGF-b 1 .TbRII was present in each of these lanes ( FIG. 8B , lanes 4, 5). Therefore, in the context of [ 125 I]-TGF-b 1 crosslinking, either an anti-TbRII antibody or an anti-Cripto antibody can precipitate complexes containing both labeled TbRII and labeled Cripto. This is similar to what is observed in crosslinking experiments with TbRII, [ 125 I]-TGF-b 1 and ALK5 in which the ligand mediates assembly of both Type II and Type I receptors into a stable complex.
EXAMPLE 7
[0000] Mutation of Threonine 72 Blocks Cripto Antagonism of TGF-b and Activin Signaling
[0086] It has previously been shown that Cripto is modified by O-fucosylation on a conserved threonine residue (Thr 72 in mouse Cripto, Thr 88 in human Cripto) within its EGF-like domain and that mutation of this threonine to an alanine blocks the ability of Cripto to bind nodal and facilitate nodal signaling. The EGF-like domain of Cripto plays an important role in facilitating nodal signaling, and results presented above indicate that it also plays an important role in blocking both TGF-b 1 and activin-A signaling. Therefore, we tested whether mutation of Thr 72 to Ala, which prevents fucosylation within this domain and blocks nodal signaling, might similarly interfere with Cripto's ability to block TGF-b and activin signaling.
[0087] FIG. 9 shows the relative effects of wild type Cripto and the Thr 72→Ala (T72A) Cripto fucosylation mutant on TGF-b 1 ( FIG. 9A ), activin-A ( FIG. 9B ) and activin-B ( FIG. 9C ) signaling. 293T cells were transfected with empty vector, wild type Cripto or the Cripto (T72A) mutant together with FAST2/A3-luciferase. When 293T cells were treated with 100 pM TGF-b 1 ( FIG. 9A ), luciferase induction relative to vector-transfected cells ( FIG. 9A , lane 1) was reduced in cells transfected with wild type Cripto ( FIG. 9A , lane 2) but was unaffected in cells transfected with the Cripto (T72A) mutant ( FIG. 9A , lane 3).
[0088] Similarly, when cells were treated with 300 pM activin-A, luciferase induction was blocked by wild type Cripto ( FIG. 9B , lane 2) but not the Cripto (T72A) mutant ( FIG. 9B , lane 3). Finally, when cells were treated with 300 pM activin-B, Cripto blocked luciferase induction consistent with our previous observations and those of others. However, unlike what was observed with TGF-b and activin-A, the Cripto (T72A) mutant could partially block activin-B signaling ( FIG. 9C , lane 3). This is consistent with a previous report demonstrating that this mutant can bind activin-B and that the CFC domain of Cripto is important for Cripto antagonism of activin-B.
EXAMPLE 8
[0000] The EGF-Like and CFC Domains of Cripto Both Participate in Blocking Activin-B Signaling
[0089] In an attempt to clarify the functional importance of the EGF-like and CFC domains on Cripto antagonism of activin-A and activin-B signaling, 293T cells were transfected with empty vector, the Cripto DEGF mutant or the Cripto DCFC mutant together with FAST2/A3-luciferase and luciferase induction was measured in response to treatment with activin-A or activin-B. Consistent with previous observations, Cripto DEGF mutant did not block activin-A signaling ( FIG. 10 ). In contrast, the Cripto DEGF mutant blocked roughly half of the luciferase activity induced by activin-B ( FIG. 10 ), indicating an independent role for the CFC domain in blocking activin-B signaling. In contrast to the Cripto DEGF mutant, the Cripto DCFC mutant strongly blocked luciferase induction by either activin-A or activin-B ( FIG. 10 ). Therefore, the EGF-like domain appears to be necessary and sufficient for antagonism of activin-A and TGF-b 1 signaling by Cripto while either the EGF-like domain or the CFC domain can apparently function independently to block signaling by activin-B.
EXAMPLE 9
[0000] The CFC Domain of Cripto is not Required for Activin-A Binding
[0090] Having demonstrated that the CFC domain of Cripto is not required for inhibition of activin-A signaling, we next tested whether this domain is required for Cripto to bind activin-A and activin-B. 293T cells were transfected with Cripto ( FIG. 11 , lane 1); Cripto DCFC ( FIG. 11 , lane 2); ActRII ( FIG. 11 , lane 3); ActRII and Cripto ( FIG. 11 , lane 4); or ActRII and Cripto DCFC ( FIG. 11 , lane 5), subjected to labeling and crosslinking with [ 125 I]-activin-A or [ 125 I]-activin-B followed by immunoprecipitation with either an anti-myc antibody targeting ActRII ( FIG. 11A ) or an anti-FLAG antibody targeting Cripto and Cripto DCFC ( FIG. 11B ).
[0091] As predicted, transfection of Cripto alone ( FIG. 11A , lane 1) or Cripto DCFC alone ( FIG. 11A , lane 1) followed by cell labeling, crosslinking and immunoprecipitation using an antibody targeting ActRII did not result in detection of crosslinked complexes. However, transfection of 293T cells with ActRII alone ( FIG. 11A , lane 3) resulted in bands at ˜80 kDa representing the [ 125 I]-activin-A.ActRII complex and bands at ˜28 kDa representing the [ 125 I]-activin-A dimer. Co-transfection of ActRII and Cripto ( FIG. 11A , lane 4) or ActRII and Cripto DCFC ( FIG. 11A , lane 5) led to precipitation of additional complexes of ˜34 kDa and ˜30 kDa likely representing the [ 125 I]-activin-A.Cripto complex and [ 125 I]-activin-A.DCFC complex, respectively. In parallel experiments, we have been unable to detect crosslinked complexes with [ 125 I]-activin-B, apparently due to loss of binding activity resulting from the iodination procedure.
[0092] We also precipitated [ 125 I]-activin-A labeled complexes with anti-FLAG antibody targeting Cripto and Cripto DCFC. When 293T cells were transfected with Cripto alone or Cripto DCFC alone, crosslinked with [ 125 I]-activin-A and then subjected to immunoprecipitation with anti-FLAG antibody, no bands were observed ( FIG. 11B ). This result is similar to what was observed with TGF-b crosslinking ( FIG. 8 ), suggesting that when transfected alone Cripto and Cripto DCFC are each unable to bind activin-A. As predicted, transfection of ActRII alone followed by cell labeling, crosslinking and immunoprecipitation using anti-FLAG antibody did not result in observation of crosslinked complexes ( FIG. 11B , lane 3). Co-transfection of 293T cells with ActRII and Cripto ( FIG. 11B , lane 4) or ActRII and Cripto DCFC ( FIG. 11B , lane 5) led to precipitation of complexes of ˜34 kDa and ˜30 kDa representing the [125I]-activin-A.Cripto complex and the [ 125 I]-activin-A.DCFC complex, respectively, providing evidence that the CFC domain is not required for binding of Cripto to activin-A. Rather, consistent with functional data, the Cripto DCFC mutant appears to bind and crosslink to [ 125 I]-activin-A more effectively than wild type Cripto as indicated by their relative band intensities ( FIG. 11B , lanes 4, 5). The ˜80 kDa band representing [ 125 I]-activin-A.ActRII was present in each of these lanes ( FIG. 11B , lanes 4, 5) indicating that in the presence of activin-A, Cripto and Cripto DCFC each can form a stable complex with ActRII.
EXAMPLE 10
[0000] Cripto Antagonizes Activin-A/TGF-b 1 But Facilitates Nodal Signaling in 293T Cells
[0093] The effects of Cripto on activin-A and TGF-b 1 signaling as opposed to nodal signaling were compared. It has previously been shown that transfection of nodal and Cripto into 293T cells resulted in secretion of processed nodal protein that generates signals in the cells producing it. Thus 293T cells were transfected with FAST2, the A3-luciferase reporter plasmid and various amounts of Cripto DNA. The cells were then treated with activin-A or TGF-b 1 or co-transfected with a mouse nodal expression vector.
[0094] FIG. 12 shows that in the absence of Cripto, activin-A treatment induced luciferase expression ˜45 fold relative to untreated cells and TGF-b 1 treatment induced luciferase expression ˜30 fold. Co-transfection with increasing amounts of Cripto DNA caused a dose-dependent blockade of activin-A and TGF-b 1 signaling. Conversely, nodal did not generate a detectable signal in the absence of Cripto but its signaling increased as the amount of Cripto DNA transfected into the cells was increased ( FIG. 12 ). Therefore, Cripto can have opposing effects on activin/TGF-b as opposed to nodal signaling despite the fact that activin and nodal utilize the same signaling receptors and each of these ligands signal via the Smad2/3 pathway.
EXAMPLE 11
[0000] Regulation of TGF-b Superfamily Signaling by Cripto
[0095] FIG. 13 illustrates proposed mechanisms by which Cripto either facilitates nodal and Vg1/GDF1 signaling ( FIG. 13A ) or inhibits TGF-b and activin signaling ( FIG. 13B ). Cripto binds nodal or Vg1/GDF1 and ALK4 and allows these ligands to assemble type II and type I receptors to elicit signaling responses such as mesendoderm induction during vertebrate embryogenesis ( FIG. 13A ).
[0096] In contrast to its effects on nodal signaling, Cripto binds activin-A in the presence of its type II receptors and antagonizes activin signaling. Cripto also inhibits activin-B signaling, although the mechanism of this antagonism appears to differ from that of activin-A. Cripto also binds TGF-b 1 in the presence of TbRII and blocks TGF-b 1 signaling, demonstrating a mechanism of antagonism similar to that on activin-A signaling ( FIG. 13B ). Type II receptor binding is required for activin-A and TGF-b 1 to form complexes with either type I receptors or Cripto, and crosslinking data presented herein indicate that Cripto may disrupt the ability of activin-A and TGF-b 1 to form functional complexes with type I receptors ( FIG. 13B ). The ability of Cripto to inhibit TGF-b 1 and activins, which are tumor suppressors and can potently inhibit cell growth, provides a mechanism by which it could promote tumorigenesis.
EXAMPLE 12
[0000] Inhibition of Activin-Cripto or TGF-b.Cripto Complexes Formation
[0097] It is hypothesized that antagonism of activin and TGF-b signaling by Cripto can be disrupted using antibodies directed against Cripto. Binding of these antibodies to Cripto is predicted to disrupt the ability of Cripto to bind to activin or TGF-b, thereby reversing the antagonism of activin and TGF-b signaling by Cripto.
[0098] Cripto has two highly conserved domains, the EGF-like domain and the CFC domain, that have been shown to be functionally important and are involved in protein-protein interactions. The EGF-like domain of Cripto binds directly to the TGF-b superfamily member nodal and related ligands Vg1 and GDF1 to facilitate signaling via activin receptors ActRII/IIB and ALK4. The EGF-like domain of Cripto is required for antagonism of activin and TGF-b signaling. Deletion of the EGF-like domain (DEGF) resulted in a Cripto mutant with undetectable activin binding in crosslinking assays and an inability to block activin or TGF-b signaling. Therefore, it is proposed that, similar to nodal, activin and TGF-b bind to the EGF-like domain of Cripto and this domain represents a primary target for antibody blockade of Cripto antagonism of activin and TGF-b.
[0099] It has also been shown that the CFC domain of Cripto binds directly to ALK4 and, similar to the EGF-like domain, this domain is required for nodal signaling. We have tested a Cripto mutant with two point mutations in the CFC domain that was previously shown to be defective in ALK4 binding and nodal signaling. This mutant, called mCFC, bound activin in crosslinking assays when co-expressed with activin type II receptors (ActRII/IIB) and blocked activin signaling when transiently transfected into 293T cells. This is consistent with activin binding to the EGF-like domain of Cripto. Consequently, antibodies that can disrupt Cripto binding to ALK4 may have effects on Cripto antagonism of activin and TGF-b. Recently it was shown that monoclonal antibodies targeting either the CFC domain (Adkins et al., 2003) or EGF-like domain (Xing et al., 2004) of Cripto can inhibit tumor growth in vivo.
[0100] Antibodies can be generated against recombinant soluble Cripto protein (containing both the EGF-like and CFC domains) purified from mammalian cells or a synthetic peptide spanning the EGF-like domain of Cripto. Raising antibodies against the full-length soluble Cripto protein will enable us to test the effects of antibodies targeting both the EGF-like and CFC domains.
[0101] Soluble Cripto with a C-terminal FLAG epitope tag can be expressed in mammalian cells (293T cells or CHO cells) following transient transfection. Cells stably expressing soluble Cripto-FLAG can be generated by selection in G418 for larger-scale production of protein. Medium containing soluble Cripto-FLAG can be enriched using FLAG-agarose immunoaffinity chromatography and purified by reverse-phase HPLC. The Cripto EGF-like domain can also be generated as a synthetic peptide to be used as an antigen to generate anti-Cripto antibodies. Peptide spanning the human Cripto EGF-like domain has previously been synthesized, refolded and shown to have biological activity. A similar polypeptide spanning the mouse Cripto EGF-like domain can be generated using mouse Cripto sequence generally available in the art.
[0102] Initially, potential neutralizing anti-Cripto antibodies can be tested at various doses for their ability to disrupt Cripto antagonism of activin-A, activin-B and TGF-b 1 signaling in 293T cells. The ability of activin-A, activin-B and TGF-b 1 to induce luciferase can be measured in cells transfected with Cripto, FAST2 and A3-luciferase constructs. The effects of the anti-Cripto antibodies can be compared to normal rabbit serum (NRS). If antibodies directed against fill-length Cripto or peptide containing the EGF-like domain are found to block Cripto effects on activin and TGF-b signaling in 293T cells, further testing can be performed using other cells including breast epithelial and breast cancer cell lines.
[0103] Alternatively, antagonistic activities of Cripto may be inhibited by molecules that bind to Cripto, thereby disrupting the ability of Cripto to bind to activin or TGF-b. For example, Lefty and Tomoregulin have each been shown to bind directly to Cripto and have been shown to block nodal signaling (nodal signaling requires Cripto). The prediction is that by binding to Cripto they might interfere with Cripto's ability to bind to TGF-b/activin thereby blocking Cripto's effects on these ligands.
EXAMPLE 13
[0000] Inhibition of Activin.Cripto or TGF-b.Cripto Complexes Formation by Soluble Mutated Activin Receptor-Like Kinases-4 (ALK-4)
[0104] The aim here is to generate a soluble version of the ALK4-extracellular domains (ECD) that is capable of binding Cripto but not a TGF-b superfamily ligand such as activin. It is hypothesized that such a protein will not bind directly to a TGF-b superfamily ligand and interfere with signaling, but rather will have the ability to bind Cripto and disrupt the ability of Cripto to block activin or TGF-b binding and signaling.
[0105] The functional binding site for activin on ALK4 has been identified recently (Harrison et al., 2003). It was demonstrated that 170A, L75A and P77A ALK4-ECD mutants were unable to bind activin or mediate activate signaling. It was concluded that 170, L75 and P77 are central to the activin binding site on the ALK4-ECD. Although mutating one of these residues is sufficient to disrupt activin.ALK4 binding, soluble versions of ALK4-ECD incorporating these mutations individually, in pairs or incorporating all three mutations can also be generated.
[0106] The soluble ALK4 ECD proteins incorporating the 170A, L75A and/or P77A mutations and a C-terminal FLAG epitope tag can be expressed in mammalian cells (293T cells or CHO cells) following transient transfection. Cells stably expressing soluble ALK4-ECD-FLAG proteins will be generated by selection in G418 for larger-scale production of protein. Medium containing soluble ALK4-ECD-FLAG proteins can be enriched using FLAG-agarose immunoaffinity chromatography and purified by reverse-phase HPLC.
[0107] Initially, soluble ALK4 ECD proteins incorporating the 170A, L75A and/or P77A mutations can be tested at various doses for their ability to disrupt Cripto antagonism of activin-A, activin-B and TGF-b 1 signaling in 293T cells. The ability of activin-A, activin-B and TGF-b 1 to induce luciferase will be measured in cells transfected with Cripto, FAST2 and A3-luciferase constructs. The mutant ALK4-ECD proteins will be compared to wild type soluble ALK4-ECD. The effects of these ALK4-ECD proteins on activin signaling in the absence of Cripto will also be tested to determine if they interfere with activin signaling. In addition to 293T cells, other cells including breast epithelial and breast cancer cell lines can also be used.
EXAMPLE 14
[0000] Inhibition of Cripto Expression
[0108] Multiple strategies can be pursued to prevent Cripto antagonism of activin and TGF-b signaling in a defined in vitro system. Useful strategies include, but are not limited to, disruption of Cripto expression by homologous recombination, the previously validated Cripto antisense vector approach, and Cripto RNA interference.
[0000] Homologous Recombination
[0109] Disruption of Cripto expression by homologous recombination in mouse embryonic stem cells has been previously described (Ding et al., 1998). It was shown that mice lacking both alleles of Cripto died very early during embryogenesis probably due to a loss of nodal signaling which requires Cripto. However, the effects of deleting one Cripto allele or of disrupting both alleles in the adult in specific tissues (i.e. conditional knockout) remains to be evaluated in terms of effects on cancer susceptibility.
[0000] Antisense Oligonucleotides
[0110] The use of antisense oligonucleotides to disrupt Cripto expression has also been described (Niemeyer et al., 1998). Retroviral vector was used to deliver Cripto antisense RNA to mouse mammary CID-9 cells. Reduction of endogenous Cripto expression in these cells via expression of an antisense Cripto vector construct decreased cell proliferation while overexpression of Cripto led to increased cell growth. Antisense inhibitors of Cripto also led to loss of transformed phenotype in colon carcinoma cells (Ciardiello et al., 1994).
[0111] Niemeyer et al. (1998) used the retroviral vector pGCEN containing the antisense Cripto sequence to infect CID-9 cells and generated cells stably expressing the antisense construct. Similar approach can be performed with the retroviral pCLNC vector, which was used previously to infect cells and generate stable lines (Gray and Vale, unpublished data). One of ordinary skill in the art would recognize that other vectors besides retroviral vectors can also be used according to standard procedures in the art. In one example, mouse Cripto sequence can be subcloned into the pCLNC vector in the antisense or the sense orientation. These constructs or empty pCLNC vector are used to generate virus, infect CID-9 cells and obtain G418 resistant cells. The effectiveness of this approach in increasing or decreasing Cripto can be measured directly by examining Cripto expression in the resulting G418 resistant cells by Western blot with anti-Cripto antibodies.
[0112] The effects of activin and TGF-b and their antagonists on the proliferation of CID-9 cell (or other target cells well-known in the art) can be measured using protocols generally available to one of ordinary skill in the art. For example, the CyQUANT® cell proliferation assay kit (Invitrogen) can be used according to manufacturer's instructions. The sensitivity of a target cell line to growth inhibition by activin and TGF-b and their antagonists can be established by treating a range of cells with a range of doses of each ligand, antagonist or vehicle and testing the effects on proliferation over time. Once the effects of activin, TGF-b or antagonist on the parental cells are established, these experiments can be repeated on cells stably expressing the retroviral vector, Cripto-sense or Cripto-antisense retroviral DNA and compare the resulting effects of various doses of activin and TGF-b on cell proliferation. It has been shown that Cripto overexpression conferred anchorage independent growth capability on CID-9 cells. Therefore, in addition to measuring the proliferation rate of Cripto over- and under-expressing cells in monolayer culture, the ability of these cells to grow in soft agar will also be measured. Similar experiments can be performed on cells stably overexpressing RNAi vectors (as described below).
[0000] RNA Interference
[0113] The principle of RNA interference is the abrogation of target gene expression initiated by small interfering RNA (siRNA) homologous in sequence to the gene to be silenced (Elbashir et al., 2001). Recently, it was shown that transfection of a synthetic 21-nucleotide siRNA duplexes could specifically suppress expression of endogenous and heterologous genes in different mammalian cell lines. Viral infection of target cells such as CID-9 cells to express a 21-nucleotide siRNAs targeted against Cripto can be performed using the U6 promoter system based on the pSilencer vector (Ambion) and/or the polymerase III HI-RNA promoter (pSUPER) (Brummelkamp et al., 2002). These RNAs require a 5′ UU overhang to bind their target genes. Therefore, target sequences for siRNAs will be identified by scanning the Cripto gene for sequences containing AA targets complementary to the siRNA UU overhang. The AA and downstream 19 nucleotides will be compared to an appropriate genome database to eliminate sequences with significant homology to other genes. Sequences that are specific to the mouse Cripto gene and are common between mouse, rat, and human Cripto will be initial siRNA targets.
[0114] Retroviral and/or lentivirus vectors (provided by Dr. Inder Verma, The Salk Institute) will be used for the infection and stable expression of siRNAs in CID-9 cells. These vectors can be designed to contain either a polymerase III HI-RNA promoter or a U6 small nuclear RNA promoter to continuously drive high levels of siRNA expression in target cells. Cripto-specific inserts can be designed such that the specified 19-nucleotide sequence of Cripto is separated by a short spacer from the reverse complement of the same 19-nucleotide sequence. The resulting transcript is predicted to fold back on itself to form a 19 base pair hairpin-loop structure necessary for siRNA function. Expression of Cripto siRNAs using these two vector systems will allow for efficient Cripto disruption.
[0115] In addition to validating this approach in cultured mouse CID-9 cells, deliverance of siRNA or antisense RNA targeting Cripto expression by retroviral or lentiviral vectors represents a potential gene therapy approach to treat human cancer.
EXAMPLE 15
[0000] Augmenting Smad2/3 Signaling Using Mutant Activin
[0116] Another method of overcoming the antagonistic effects of Cripto on activin and TGF-b signaling (i.e. Smad2/3 signaling) is to design a mutant form of activin (or possibly TGF-b) that retains signaling activity but is unable to bind Cripto. Such a mutant ligand may have therapeutic value since it will be capable of activating Smad2/3 signaling in tissues in which signaling by wild type activin and TGF-b is otherwise suppressed by Cripto.
[0000] Cripto-Resistant Activin
[0117] In an effort to identify receptor-binding residues on activin-A, a rapid functional screen for expressing and characterizing activin-A and activin-A mutants has been established using 293T cells. This system incorporates FAST2 and A3-luciferase and is based on a system originally developed to characterize nodal and Cripto signaling. Full-length activin bA cDNA has been expressed in 293T cells and dimeric, processed activin-A was secreted into the medium. When conditioned medium from these cells was used to treat separate 293T cells transfected with A3-luciferase and FAST2, luciferase reporter expression was induced, indicating the secreted activin-A was fully active.
[0118] Using the above system, several activin-A mutants were generated and quantitated from conditioned medium by Western blot analysis. We have confirmed previous results indicating that mutation of Lys 102 to Glu (K102E) disrupts activin-A activity. However, most of the mutants we have generated appear to retain full activity. We now propose to compare the ability of transfected Cripto to antagonize wild type activin-A signaling in 293T cells with its ability to antagonize these activin-A mutants. The goal is to identify activin-A mutants that are resistant to Cripto antagonism relative to wild type activin-A. Additional activin-A alanine substitution point mutants can be generated with the aim of identifying activin-A mutants with Cripto full signaling activity and Cripto resistance.
EXAMPLE 16
[0000] 5 Constructs and Uses of Soluble and Membrane-Bound Cripto
[0119] Cripto is expressed at high levels in tumors and has been shown to promote tumorigenesis, whereas TGF-b and activin are tumor suppressors and potently inhibit cell proliferation. Paradoxically, TGF-b/activin can also promote tumorigenesis at later stages of tumor progression when tumor cell proliferation is no longer inhibited by TGF-b/activin signaling. At these later stages, TGF-b and activin are produced at high levels by tumor cells and signaling of these ligands causes angiogenesis, immunosuppression and epithelial to mesenchymal transition which favor tumor growth and spread. Threrefore, it may be of therapeutic value to either facilitate TGF-b/activin signaling or to block TGF-b/activin signaling depending on the context (i.e. stage of tumor progression).
[0120] Blocking TGF-b/activin signaling may have therapeutic benefit in several contexts including, but are not limited to, cancer, wound healing and liver regeneration. As mentioned above, during later stages of tumorigenesis tumor cells secrete TGF-b and activin that cause effects favoring further tumor growth and metastasis due to their effects on blood vessels, cells of the immune system and organs which are targets for metastasis. Directing Cripto expression or administering soluble forms of Cripto to these sites may help to slow tumor progression.
[0121] TGF-b and activin accelerate wound healing but they also can cause excessive extracellular matrix deposition and unwanted scarring. Cripto may therefore have utility as a modulator of TGF-b/activin in this context. With regard to liver regeneration, TGF-b and activin are potent antiproliferative agents in liver and therefore blocking their signaling with Cripto may prove useful in facilitating liver regeneration.
[0000] Design of Cripto Mutants
[0122] Examples of Cripto constructs are indicated in FIG. 14 . Initially, all constructs can be generated in mammalian expression vector such as pcDNA3 using standard PCR-based mutagenesis and subcloning techniques.
[0123] Cell-attached Cripto constructs can incorporate Cripto signal peptide with an in-frame epitope tag sequence (e.g. FLAG or His) immediately downstream of the signal peptide followed by the indicated Cripto sequences ( FIG. 14 ), hydrophobic C-terminal domain required for GPI attachment and a stop codon. The Epidermal Growth Factor-Cripto, FRL-1, Cryptic (EGF-CFC) region of mouse Cripto (aa 60-134) has been shown to be sufficient to reconstitute one-eyed pinhead (oep) signaling in zebrafish embryos. This region can be expressed as a cell-attached protein and tested for its ability to bind activin and TGF-b and antagonize their signaling ( FIG. 14 ).
[0124] The EGF-like domain of mouse Cripto spans residues 60-95 ( FIGS. 14-15 ) and deleting this region abolishes the ability of Cripto to bind activin-A as well as its ability to antagonize both activin-A and TGF-b 1 signaling. Cell-attached EGF-like domain construct can be tested for its effects on activin-A and TGF-b 1 binding and signaling. The effects of the GPI-anchored CFC domain (aa 99-134) on activin-A and TGF-b 1 binding and signaling can also be tested.
[0125] The functional role of individual amino acid in the Cripto EGF-like and CFC domains for activin-A and TGF-b 1 binding can be determined as follows. Mutants such as Cripto mCFC (H104G, W107G), which has two point mutations within the CFC domain and does not bind ALK4, and Cripto DEGF, which has the entire EGF-like domain deleted and is unable to bind the TGF-b/activin-related ligand nodal, have been described above. Mutant Cripto EGF1.2mCFC, which blocks Cripto binding to activin and prevents Cripto antagonism of activin and TGF-b signaling, incorporates mEGF1, mEGF2 and mCFC tandem point mutations (N69G, T72A, R88G, E91G, H104G, W107G) (see FIGS. 14-15 ). The effects of these mutations, individually or in combination, can be tested by incorporating these or the corresponding alanine mutations into cell-attached or soluble Cripto constructs. For example, overlapping PCR mutagenesis can be used to generate these point mutations in full-length, GPI-anchored Cripto background. Similar mutations can also be generated in soluble EGF-like and CFC domain constructs.
[0126] Furthermore, there are 14 highly conserved residues in the EGF-like domain and 9 highly conserved residues in the CFC domain ( FIG. 15 ). Fifteen of these conserved residues have previously been targeted for mutagenesis in the context of soluble mouse Cripto and characterized with respect to their ability to reconstitute one-eyed pinhead (oep) signaling in zebrafish embryos lacking both maternal and zygotic expression of oep (MZoep). RNA encoding soluble mouse Cripto or soluble EGF-CFC region could restore normal embryonic development as could the soluble Pro52, Phe85, His92, Arg95 and Glu97 Cripto Ala-substituted mutants (Minchiotti et al., 2001). Injected RNA encoding the Gly71Asn or the Phe78Ala mutants was unable to rescue the MZoep phenotype even at high doses while the Asn63, Ser77, Arg88, Glu91, His104, Leu114, Leu114, Leu122 and Arg116 Ala substituted mutants resulted in intermediate effects (Minchiotti et al., 2001). Each mutant was expressed in 293T cells and it was shown that with the exception of the Arg88Ala mutant, each of the fifteen mutants was expressed at approximately wild type levels (Minchiotti et al., 2001). To more fully characterize the activin and TGF-b binding site(s) on Cripto, similar study can be done with Ala substituted mutants in the context of full-length, GPI-anchored Cripto constructs or soluble Cripto constructs. It is expected that conserved residues within the EGF-like domain may constitute the activin and TGF-b binding surfaces.
[0127] It has been previously shown that Cripto can facilitate nodal signaling and activate mitogenic MAPK and PI3K pathways when present as a soluble protein, raising the possibility that Cripto may act both cell autonomously and as a secreted, soluble factor. Thus it is of interest to test the ability of several soluble Cripto constructs to bind activin and TGF-b and antagonize their signaling. Examples of soluble Cripto constructs are illustrated in FIG. 14 . It has been previously shown that the C-terminal hydrophobic domain of Cripto is required for GPI-attachment and deletion of this domain results in secretion of soluble Cripto protein. Therefore, soluble Cripto constructs will incorporate this C-terminal deletion in addition to an in-frame C-terminal FLAG epitope tag followed by a stop codon ( FIG. 14 ).
[0128] The following references are cited herein:
Adkins et al., Antibody blockade of the Cripto CFC domain suppresses tumor cell growth in vivo. J. Clin. Invest. 112:575-87 (2003). Brummelkamp et al., A system for stable expression of short interfering RNAs in mammalian cells. Science 296:550-3 (2002). Ciardiello et al., Inhibition of CRIPTO expression and tumorigenicity in human colon cancer cells by antisense RNA and oligodeoxynucleotides. Oncogene 9:291-8 (1994). Ding et al., Cripto is required for correct orientation of the anterior-posterior axis in the mouse embryo. Nature 395:702-7 (1998). Elbashir et al., Duplexes of 21-nucleotide RNAs mediate RNA interference in cultured mammalian cells. Nature 411:494-8 (2001). Gray et al., Cripto forms a complex with activin and type II activin receptors and can block activin signaling. Proc. Natl. Acad. Sci. USA. 100:5193-8 (2003). Harrison et al., Identification of a functional binding site for activin on the type I receptor ALK4 . J. Biol. Chem. 278:21129-35 (2003). Minchiotti et al., Development 128:4501-10 (2001). Niemeyer et al., Cripto: roles in mammary cell growth, survival, differentiation and transformation. Cell Death Differ. 5:440-9 (1998). Xing et al., Cancer Res. 64:4018-23 (2004). Yeo and Whitman, Mol. Cell 7:949-57 (2001).
[0140] Any patents or publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. Further, these patents and publications are incorporated by reference herein to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. | Cripto, a developmental oncoprotein, antagonizes activin and TGF-b signaling by forming a complex with activin and TGF-b and their type II receptors. This complex precludes the formation of a functional activin/TGF-b.type II.type I complex, thereby blocking the signaling of activin and TGF-b. Cripto may be generally capable of blocking antiproliferative Smad2/3 signals and provides a novel mechanism of oncogenic action with multiple therapeutic implications. Inhibiting the formation of Cripto and activin/TGF-b complex may enhance antiproliferative effects of activin and TGF-b. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to a method for producing a textured, voluminous non-woven web or velourized film from a thermoplastic by producing a non-textured web and subsequently processing said non-textured web using a pair of rollers. Said pair of rollers consists of a positive roller having numerous positive projections distributed over the roll sleeve surface and a negative roller having equally as many cavities. During the rolling process, the positive projections mesh with the cavities and stretch the web in the area of the roller engagements in such a manner that a deep-drawn web texture with numerous cavities is produced.
The above-mentioned method is used in particular for the production of textured, voluminous non-woven webs (DE 195 47 319 A1). For this, a raw web consisting of a large number of individual filaments or of staple fibers is produced from which a raw non-woven web is produced. This raw web is post-processed by a second pair of rollers, whereby the projections engage the cavities and stretch the raw web in the areas of roller engagement.
A similar method can also be used on a non-textured film or velour film, as is known from DE 195 24 076 C1.
Further, a device used to create a moisture-permeable film in which a film of thermoplastic material is heated to the point that adopts a deformation temperature approximating the thermoplastic temperature of the material is known from DE 78 04 47[8] U1. At this temperature, the film is inserted into a pressure gap and shaped during pressing and simultaneous cooling at the thermoplastic temperature range. The pressure gap is formed between a cooled and an engraved metal cylinder and an elastic roller. Behind the pressure gap, the film is further cooled while lying on the metal cylinder. Then the ends of the pressed items formed are caused to shrink by brief heating to, or above, the temperature used to shape the material, causing the openings to be formed.
This known method relates only to smooth film, however, and employs a temperature and shrink cycle that must be adjusted exactly. This results on the one hand in the limitation to a particular raw material, and on the other hand in a complicated temperature process.
SUMMARY OF THE INVENTION
The task is to provide an aperture, perforation, or thinning in the areas provided with cavities at the base of these cavities of a film or web produced in the known manner so that vapor or moisture permeability is possible through these perforations. The invention is therefore in the realm of technology of the production of perforated, three-dimensional webs, particularly as used for disposable hygienic products. For this, the particular task is to expand the method already developed in a relatively simple manner so that the three-dimensional, textured web produced according to that method is provided with perforations at the cavities in a reliable manner without requiring alteration to the basic procedure steps.
This task is solved by an invention manifested in two basic embodiments, whereby a textured web is produced in both cases that is more permeable than the non-textured web.
On the one hand, the method mentioned initially may be so expanded that, after the web has passed through roller gap, the deformed web still adhering to the positive roller may be contacted in the areas of the tips of the projections by a perforating, tearing tool that perforates and particularly tears it, whereby at least one perforation or thinning is created at the base of the cavities.
This procedure first deforms and then creates perforations. The reverse is also possible: the perforation may be implemented and then is torn further starting from the initial perforation. For this, it is recommended that, before the non-textured web is passed through the roller gap, it is perforated or thinned at the tips of the projections by a tool, and at least one perforation or thinning in the area of the base of the future cavities is implemented, and that the positive projections that engage into the cavities and stretch the web in the area of the roller engagement areas should further rip out the cavities at their tips and/or thin them during the rolling process.
Both procedure options represent embodiments of the invention, namely the basic concept that a padded web, namely a non-woven web or velour-textured film, will produce increased tension at the tip areas that is compensated in the course of the procedure and over a certain rest time, but will lead at the moment of formation to the fact that an existing rip or thinning will increase or stretch, so that a perforation or thinning (depending on the material selected) will arise at the desired location. The method is particularly suitable to the method known from DE 195 47 319 in which a non-woven web is used to produce a raw web that consists of a large number of individual filaments that are stretched and positioned irregularly into a fiber position whereby the initial stretching of the individual filaments occurs only in the area of 50% to 70% of their maximum possible length, and are subsequently pressed and welded, and are then processed in this form. The post-processing is then performed by engaging the projections that stretch the raw web in the area of roller engagement, leaving corresponding perforations behind.
It is also possible, however, to use another roller generally to perforate or thin the web that contacts the positive roller after the web has passed over it but is still in contact with it. Needle or heated rollers are the most suitable for this. Needle or heated rollers can be operated at a temperature of 140° C. to 200° C. in the contact areas.
The texturing of the product manufactured by the method based on the invention is improved in that the negative roller includes engraving that is the inverse of engraving on the positive roller, so that when the rollers are removed, protuberances, such as strips and projections arranged on the surface of one of the rollers, mesh with matching grooves and cavities on the surface of the opposite roller.
The projections on the positive roller are advantageously-arranged projections, and the surface of the negative roller includes laminated strips arranged parallel to the axis with cavities positioned between them, so that when the rollers rotate, the laminations mesh in the gaps held free by the projections.
The rollers of the roller pair can be made of metal. In particular, the metal for both rollers should possess the same Rockwell (HRC) hardness exceeding 50 HRC.
It is particularly advantageous to use rollers for the positive and negative rollers that include a metal core and whose roll sleeve surface is formed by a plastic coating of the roller core. Such a plastic sleeve can, in particular, be engraved by laser, whereby the roller may be quickly and cheaply provided with any type of pattern. Since an engraving laser may be very accurate and fully automated, the pattern can be applied with such high precision to the extent that it is possible to provide the plastic-coated surfaces of the positive and negative rollers with very fine patterns that engage each other.
The height of the projections is preferably between 0.8 and 2 mm. The three-dimensional texture of the non-woven web is in the foreground.
The mutual linear separation of the projections should be between 1 and 2.5 mm. The quantity of projections on 100 cm2 of roller surface is preferably between 2,000 and 3,000.
The projections can be produced in various pointed forms, e.g., they may be formed like an onion-shaped tower or a pyramid with a tip angle of 90°±20°.
The rollers can be at different temperatures during the procedure, whereby the temperature of the negative roller is preferably at a temperature at least 20° C. cooler than that of the positive roller.
Polyethylene, polypropylene, polyamide, polyvinyl alcohol, polyester, polyetherester, or polycarbonate has proved to be suitable as raw material for web production.
In general, all thermoplastics from which textured film may be produced according to known methods are suitable. Materials that are produced from the above-mentioned thermoplastics according to the spun-melt, carding, air-laid, spun-laced, or melt-blown procedures may be used for non-woven webs.
In order to improve stretching, it is recommended that the web be held tight at the roller edges during all stretching and perforating processes.
Surprisingly, a non-woven web, a film, or a velour film may be used as raw material that is passed through a roller pair consisting of a projection and a matrix roller, and, after being forced through the roller gap, is perforated by a heating roller pressed against the velour film at the projections, under friction if necessary. Manufacturing procedures for such velour films are known from Patent DE 195 24 076. Using this procedure, it is possible to create a hole in the base of the depression, so that the depression represents a small funnel. Total perforation of the non-woven web or other web is achieved, whereby the three-dimensionality already created, or to be created in a future step, is preserved. It is remarkable that the production speed could be increased to a rate of 300 meters per minute during the testing stage. This speed may particularly be increased by use of a higher projection roller temperature and a significantly lower negative roller temperature.
Additional pressing of the shaped web against the shaping positive roller can widen the opening. Fibers remaining there can be removed or melted off. The aperture structure of the non-woven web or web is thus improved.
Arranging a roller device as a part of a device to perform the above-mentioned procedure modifications is characterized in that the positive roller provided with positive bodies meshes with a negative roller, and an additional positive roller is placed after the roller pair whose positive areas coincide with the cavities of the negative roller as they rotate.
A needle roller may be placed after the roller pair by means of which the web still lying on the positive bodies and already provided with cavities may be perforated. A particularly dense needle roller that has at least 5 to 30 needles per cm2 of roller surface is required for this.
The above-mentioned second version of the procedure works in the opposite manner. For this, a precisely-textured, heated needle roller is required to effect the desired pre-perforation of the web. In the subsequent roller progression, the existing perforation is expanded and stabilized by the engagement of the positive roller. A matrix roller is placed in the middle of the roller stack. The positive roller is positioned below it. A heatable needle roller is positioned at the top of the roller stack that is provided with individual needles or groupings. The localization of the individual needles or groupings is compatible with the projections of the positive roller during their rotation. The needle roller rotates synchronously with the positive roller, and perforates a web as it passes through the first process at the locations where cavities will be created in a future step.
For this, the temperature of the needle roller at the tip of the needle is raised to 140° [and] 250° C. if dealing with polyethylene or polypropylene. This temperature is higher for polyesters and other plastics, e.g., 180° to 300° C.
The needle roller perforates the web mechanically or melts fibers or film, so that a stable pre-perforation is achieved. The web extracted from the positive roller also evinces a clear, defined opening after the cavities are established. Three-dimensionality is preserved. Thus, the opening made by the needle roller is very small, e.g., 0.05 to 0.1 mm in diameter. This diameter is then enlarged to 0.5 to 1.4 mm by the intentional engagement of the projection roller. The web material is selected to be suitably elastic.
For a full understanding of the present invention, reference should now be made to the following detailed description of the preferred embodiments of the invention as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically the manufacturing process of a three-dimensional textured non-woven web or film provided with holes.
FIG. 2 an enlarged detail from FIG. 1, namely a roller arrangement.
FIG. 3 a roller arrangement in another embodiment.
FIG. 4 another embodiment of roller arrangement.
FIG. 5 another embodiment of roller arrangement.
FIG. 6 an example of a three-dimensionally-textured film in schematic representation.
FIG. 7 a cross-section of another film texture.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiments of the present invention will now be described with reference to FIGS. 1-7 of the drawings. Identical elements in the various figures are designated with the same reference numerals.
FIG. 1 shows schematically the production process for a textured, voluminous non-woven web. A thermoplastic granulate, e.g., a polyethylene, polypropylene, polyamide, polyvinyl alcohol, polyester, polyether ester, or polycarbonate from which a web is to be produced is stored in a supply silo 1 . It is passed to a heatable extruder 2 , where it is plasticized and transferred by the extruder worm feed 2 ′ to the extruder nozzle 3 . Then the extrudate is fed via a guide nozzle 4 to a spinner jet, and, using the so-called spun-laced process, it is cooled and stretched as a filament in an attenuator 18 . Here, the individual fibers are not fully stretched. A degree of stretching of only about 60 to 70% for polyethylene and polypropylene, or 50 to 70% for polyesters or polyamide, is advantageous. This is in contrast to the normal stretching conditions that indicate as full degree of stretching as possible, which is preferred on grounds of materials efficiency. In a so-called disperser 19 , the fibers are tangled with each other and cooled (cooling fan 22 ). The stretched spun filament 6 is deposited on a net transport 7 that has a vacuum frame 8 below it, so that the tangled fibers lie flat on the net transport 7 . It is then compressed between a first roller pair, namely calender rollers 9 a and 9 b . After processing, a raw non-woven web 12 is obtained. This has a surface weight of about 20 g/m2 and is only a few millimeters thick.
The raw filament then passes to a roller stack 20 . The roller stack contains three rollers arranged on top of one another. Then the raw web 12 passes through the roller gap 21 between the two rollers 10 a and 10 b . Roller 10 a is a positive roller with numerous projections distributed over the roller sleeve surface, as may be seen in FIG. 2 . The projections may have the shape of a truncated pyramid or truncated sphere, or they may be pointed, e.g., as a pyramid with a tip angle of 90°±20°. After the web 12 has passed through the roller gap 21 , the shaped web still adhering to the positive roller 10 a at the tips of the projections is then passed through the next roller gap 41 , where another negative roller 31 is positioned, but that is so arranged that the corresponding positive parts press against the projection exteriors and cause a perforation of the shaped web 12 in the area of the projection tips, which is expanded because of the tension. The film is then drawn over the top of the stack, and is now a three-dimensional textured film with defined apertures. The film is again pressed against the shaping projection roller, whereby the non-woven web aperture is formed and widened. The remaining fibers are removed or melted off.
A velour film may be used instead of a non-woven web. FIG. 3 shows an example of processing such a film. The film passes as a non-textured web 32 with a material thickness of 60 mm with its velour side facing the projection roller 10 a into the roller gap 21 . In the roller gap 21 , the non-textured web 32 is shaped and provided with a three-dimensional texture with numerous fine cylinders. The texture corresponds to that of the roller surface. A steel roller 23 heated to 140° C. is pressed against the roller 10 a and is driven with light friction against the roller 10 a . The heated roller that has a non-friction surface moves against the roller 10 a rolling past it and causes an opening of the shrunken film and a tearing in the base area of the cavities. This forms a small funnel that has an opening at the bottom. After the second shaping step, the perforated and three-dimensionally shaped film is removed from the roller 31 , and is cooled and wrapped up. The surface includes an even, very fine velour effect. Production of the film as such is described in Patent DE 195 24 076.
In particular, the multi-layer method described in that patent is used. The upper layer is 40 mm thick, and the rear layer is 20 mm thick. The upper film is a mixture of two HDPE products made according to the Metallocen procedure. The film additionally contains lubricants, pigments, stabilizers, and a parting compound. An HDPE is used that has a lower melting index for the rear side. The film can be produced and provided with a velour surface using the known Chill-Roll procedure. The projections created during the velour effect can also be stretched. Instead of the steel roller 23 , a very dense brush roller with steel tips can be used. A film is fed into the roller gap 21 , and then the brush roller is applied against the projections, so that thinnings and perforations result in the shaped film. Then the pre-textured depressions are pressed again, creating a very clear three-dimensional texture with openings in the bases of the cavities.
In this example, the negative roller 10 b is at a temperature of 40 to 60° C., the center roller about 150° C., and the upper negative roller 31 is at a temperature of from 40 to 60° C. The brush roller may also be heated to a temperature of 120 to 150° C. FIG. 4 shows a roller arrangement in which the non-textured web 32 is fed into a roller gap 25 , whereby a needle roller 24 perforates or thins the material at the eventual tip area of the projections 11 before the non-textured web 32 passes through the roller gap 21 , and at least one perforation or thinning is created in the base area of the cavity to be formed later. The film is then passed into roller gap 21 , where the positive bodies, i.e., projections 11 , engage into the cavities and stretch the web 32 in the areas of roller engagement. This causes further rips and/or thinning in the tip areas of the cavities. The textured and perforated web is removed from the roller 10 a and passed on for further processing.
At this time, the temperature of the roller 10 a is about 140 to 160° C., while the temperature of the roller 10 b is only about 40° C. Needle tips of the needle roller 24 are heated to about 160° C. The roller stack shown in FIG. 4 may be used for non-woven web or films.
FIG. 5 shows another option. Here, a textured or roughened or velourized film, or non-textured web 32 , is fed into the roller gap 21 between a positive roller 10 a and a negative roller 10 b , and is subjected to initial texturing. By means of a heated roller 26 at a temperature of 120 to 130° C. and operating using light friction, the web lying on the projections 11 is ripped, i.e., provided with perforations and thinnings. Then the web is again fed into a gap 25 between a negative roller 27 and the positive roller 10 a , where it is again deep-drawn and stretched. This roller is at a temperature of 60° C. The film material is again stretched so that the latent thinnings and perforations that are relatively small are enlarged, and an even three-dimensional texture with openings at the bases of the cavities results. The textured film 33 is removed by a film remover roller 34 and passed to a storage facility. An initial film based on polyethylene with elastic properties that is produced as a two-layer film is used for this. The film is provided with 2.5% titanium oxide and a lubricant. The initial film has a thickness of 50 mm, for example, and may then be used for hygienic applications. It possesses a rapid absorption capability of moisture and includes excellent re-wetting values because of its three-dimensionality. The film may acquire a very “dry grip” by the addition of kaolin, chalk, or titanium oxide.
FIG. 6 shows an enlarged, schematic representation of a film texture. One may recognize that the depressions 120 have the shape of a truncated pyramid, and include perforations 122 at the bottoms of the cavities. The depressions are separated from one another by strips 121 . The scale may be derived from the “1 cm” legend.
FIG. 7 shows a similar texture. Here, a velour film is used that is provided with very fine cylindrical depressions that are also open at their bases.
There has thus been shown and described a novel method and device for producing a textured, voluminous non-woven web or film which fulfill all the objects and advantages sought therefor. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is to be limited only by the claims which follow. | The invention relates to a method for producing a structured, voluminous non-woven web or velourised film from a thermoplastic by producing an unstructured web and subsequently processing this web using a pair of rollers ( 10 a , 10 b ). The pair of rollers consists of a positive roller ( 10 a ) having numerous positive bodies distributed over the roll sleeve surface and a negative roller ( 10 b ) having equally as numerous cavities. During the rolling process, the positive bodies engage with the cavities and stretch the unstructured web in the area of the roller engagements in such a way that a deep-drawn web structure with numerous cavities is produced. After the web has passed through a roller gap, the deformed web, still bonded to the positive roller, is brought into contact with a perforating tool and perforated. | 3 |
This application is a Continuation-in-Part of International Application PCT/CH94/00130, filed Jun. 24, 1994, United States designated.
This application is a Continuation-in-Part of International Application PCT/CH94/00130, filed Jun. 24, 1994, United States designated.
FIELD OF THE INVENTION
The present invention relates to a drive system which includes a centrifugal clutch, which is so designed that, upon blocking of a driven output shaft, the clutch immediately, automatically and inherently, disconnects the output shaft from a driving or input shaft, and more particularly to rotary machinery, such as saws, boring machines and the like, especially for cutting, or handling aggregates, such as concrete, stoneware, masonry or the like, designed for transmitting substantial torque forces, and in which blockage of the rotating part of the equipment may cause damage thereto and, in a worst case, destruction thereof.
BACKGROUND
Centrifugal clutches are well known; they are used, typically, to connect a drive motor or engine to a load, while permitting the motor or engine to come up to speed from stopped condition without any substantial loading being initially placed thereon, and connecting the design load only when a predetermined speed, at which full torque is developed, has been obtained.
Centrifugal clutches use centrifugal weight which are connected to a coupling element which, in turn, is coupled or connected to a shaft driven by the motor. The centrifugal weights are, customarily, moved due to the rotary movement of the coupling element against the inner surface of a second coupling element which, usually, is drum-shaped or cup-shaped, or bell-shaped, and connected to the output shaft which, in turn, is then connected to the using equipment or machine, for example a rotary cutter, a saw, or other device. When the drive shaft rotates, the engagement force of the centrifugally acting weights becomes effective with the square of the speed. Consequently, by friction, the output shaft and the load connected thereto is gently started, since the increase in speed, due to the initially low frictional engagement of the centrifugally acting element is also still low. When synchronism has been achieved between the driving shaft and the output shaft, the pressure, and hence frictional force of the centrifugal weights is high.
If the output shaft is suddenly blocked, for example if a saw blade coupled thereto meets an obstruction, the clutch is subjected to excessive wear and tear since the driving shaft, in spite of the blocking of the output shaft, continues to rotate, and the frictional engagement force of the centrifugally acting elements continues.
When high power is to be transmitted, blockage of the output shaft can lead to red-hot overheating of the friction surfaces which are customarily present between the centrifugal weights and the cooperating clutch drum within a few seconds, and hence lead to destruction of the clutch mechanism. Repairs require that the entire machine be stopped, parts disassembled and exchanged, all of which is time-consuming and expensive. Additionally, the shock of the sudden blockage is fed back to the driving motor.
THE INVENTION
It is an object to provide a drive system with a centrifugal clutch in which, in case of blockage of the output shaft, the clutch will immediately disconnect, so that not only will the clutch be protected against overheating, but also shocks transferred back to the driving motor or engine are also eliminated. This decoupling should be effected without any external control equipment. It is an additional object of the invention to provide a drive system for rotary apparatus particularly adapted to handle heavy loads, such as aggregate cutters or saws, concrete or aggregate boring machines, snowblowers or the like, where rocks or stones in the snow mass to be blown may cause blockage of a rotary apparatus or the like.
Briefly, the centrifugal weights are coupled to a clutch portion which is connected to the output shaft, and an additional friction force torque transfer arrangement is provided to transfer some torque from the driving shaft to the output shaft, insufficient to operate the output shaft at rated speed and torque, but enough to permit initial rotation of the output shaft when unloaded, so that centrifugal forces can act on the centrifugal weights. Thus, at no load, and at speeds substantially below a predetermined operating speed, the output shaft is driven with slip between the driving or input shaft. As the speed of the output shaft increases, the frictional engagement of the centrifugal weights becomes increasingly effective--with the square of the speed of the output shaft. Full torque is then available from the output shaft. In case there should be a sudden blockage of the output shaft, the engagement force of the centrifugal weights--which is based on speed--will cease immediately and only the small residual torque used to start the clutch in operation will continue to be effective--which, however, can be easily controlled to a level where it does not cause damage, by suitable matching of the frictional elements connecting the driving or input, and the clutch output shafts.
In contrast to centrifugal clutches of the prior art, thus, the centrifugal weights are not located on the driving or input or first side to the clutch but, rather, at the driven or output or second side of the clutch.
Frictional elements which are continuously effective between the input or driving and output or driven shaft act in addition to the centrifugal coupling between the driving and driven shaft. Upon starting a motor, for example, coupled to the input or driving shaft, the output or driven shaft will be carried along, with substantial slip between the clutch elements coupled to the respective shafts. As the speed of the input shaft increases, and the speed of the output shaft likewise increases, the centrifugal weights begin to become effective until the clutch is in full engagement, and synchronism between the driving and driven shafts is obtained.
Upon sudden blockage of the driven or output shaft, the shaft of course will stop so that, inherently and without time delay, the centrifugal force also ceases to act on the weights and, hence, the forceful engagement of the centrifugal weights with the clutch part coupled to the input shaft no longer pertains. Consequently, the clutch parts coupled to the input shaft are disconnected and protected against overloading; the clutch cannot overheat. Only the relatively low, easily controlled frictional force between the driving and driven shaft will be effective. After the reason for the blockage has been removed, normal operation can be immediately resumed, without stopping and restarting the driving motor or any repair being necessary.
The particular clutch arrangement is especially suitable for boring apparatus or other cutting apparatus operating in aggregate material, such as in rocks, in concrete structures such as roadways or the like. If, for example, a concrete cutter or saw blade hits a blocking obstruction, for example a reinforcing rod or a very hard aggregate component, the centrifugal clutch in accordance with the present invention immediately separates the power transmitted by the motor from the load coupled thereto through the clutch. This immediate, inherent separation will prevent breakage of a milling cutter or a saw blade, or a boring tool used in a concrete boring machine. Damage to any one of the elements coupled to the clutch is thus effectively prevented.
The clutch is also particularly useful in snow-blowing machines, and especially road snow blowers, where rocks and large stones may be embedded in snow which has slid over a roadway. A rock can block the snow blower mechanism, causing immediate stoppage thereof and damage to the transmission mechanism. Use of the present invention prevents damage to the transmission of torque to the snow removal mechanism as such, so that, after clearing of any obstructions, the snow removal can proceed immediately. The clutch can be used in any apparatus where protection against blockage should, or must be provided.
DRAWINGS
FIG. 1 is a schematic longitudinal sectional view through a drive system in accordance with the present invention;
FIG. 2 is a transverse sectional view along the section line II--II of FIG. 1;
FIG. 3 is a fragmentary sectional view similar to FIG. 2, and illustrating another embodiment;
FIG. 4 is a schematic illustration of a concrete roadcutting machine, using the clutch of the present invention;
FIG. 5 is a schematic, essentially sectional view of another embodiment of the centrifugal clutch, particularly useful for the cutting or sawing machine of FIG. 4; and
FIG. 6 is an enlarged fragmentary view of the portion within the circle C of FIG. 5, and illustrating a detail of a centrifugal weight.
DETAILED DESCRIPTION
Referring first to FIGS. 1 and 2: The centrifugal clutch 1 is located within a housing having an essentially cylindrical outer jacket. The housing is formed of two housing parts 3, 5 which are removably connected together by an interengaging fit as shown. They are held together by suitable clamping screws or the like, not shown, since such connections are well known. One end of the housing portion 5 is coupled to a motor housing 11, or to any other suitable structure e.g., a frame, for example holding a drive wheel, pulley or the like. The drive shaft 2 is operatively coupled to a motor or engine, for example a Diesel engine or an electromotor, if necessary with the interposition of a transmission.
A first clutch element 6 is secured to the drive or input shaft 2 to reliably rotate therewith. The first clutch part 6 is somewhat drum-shaped, or bell-shaped, having an essentially cylindrical drum-like portion 7. The portion 7 has, a cylindrical friction surface 8. The friction surface 8, as seen in FIG. 1, is at the inside of the drum-like part 7. The drive shaft 2 and the first clutch element 6, preferably, are formed as two parts, as shown coupled together for example by a spline and set-screw or pin connection, since it is easier to make it that way. Alternatively, the clutch part 6 and the shaft 2 can be one integral unit. The clutch part 6 and the drive shaft 2 are rotatably retained in the housing 5 by a ball bearing 10, located in the part 5 and held therein in shoulders 9.
A second clutch part 14 is connected to the driven or output shaft 4, projecting from a hub 18. The output shaft 4 engages within a coaxial bore of the driving shaft 2; it is rotatably retained in the housing part 3 by a ball bearing 10'. Preferably, the driving and driven shafts are supported coaxially with respect to each other by another rotating bearing, for example and preferably a needle bearing 12 interposed between the inner end portion of the shaft 4 and a blind bore in the first clutch part 6, or the drive shaft 2, respectively, if the clutch part 6 and the drive shaft 2 are one single element. The driven or output shaft 4 and the second clutch part 14 can also be constructed as a single unitary element. The output end of the output shaft 4 is formed as a coupling stub 26 for connection to an output machine or unit, for example a core boring machine.
In accordance with the present invention, centrifugal weights 16 are located on the output side, or the second coupling part 14. As best seen in FIG. 2, the second or output coupling part 14 retains a plurality of circumferentially uniformly distributed centrifugal weights 16. Preferably, three or six weights are used. The centrifugal weights 16 are located loosely in recesses between essentially triangular-shaped portions 17 of a disk-shaped portion 13 of the clutch part 14. The centrifugal weights 16 have radial play. Each one of the centrifugal weights 16 is formed with a central, axially directed blind bore 20 (FIG. 1) in which a spiral spring 22 is engaged. The spiral springs 22, when the clutch is assembled, are somewhat prestressed and engage on the one hand against the bottom of the blind bore 20 in the centrifugal weight 16 and, on the other, against the disc portion 13 of the output, or second clutch part 14. The springs 22 provide for a pressure on the centrifugal weights 16 against the axial surface 24 of the drive, or first coupling part 6. Thus, a continuously effective friction connection between the drive, or input or first shaft 2 and the driven, or output, or second shaft 4 is obtained. This frictional engagement, or frictional connection is so designed to be of such strength--or rather weakness--that, when the motor is coupled to shaft 2 is started, the output or driven shaft 4 is initially carried along with slip. The motor may be an electric motor, a hydraulic motor, or any other engine or drive source.
Operation
Upon starting the drive source coupled to the input or driving shaft 2, the weak frictional force between the axial end faces of the centrifugal weights 16 against the axial surface 24 of the input coupling part 6 causes the output shaft 4 to be carried along, with slip. As the speed of the driving or input shaft increases, the centrifugal weight 16 will likewise be rotated at higher speed and, under the effect of centrifugal force will be pressed outwardly and effect additional and strong friction at the axial inner friction surface 8 of the input clutch part 6. This further increases the speed of the output shaft 4, until the output shaft 4 is accelerated to synchronism with the input shaft 2.
The engagement force of the centrifugal weights 16 increases with the square of speed. The engagement pressure, and hence the friction between the centrifugal bodies 16 and the driving clutch part 6 will, when the nominal speed of operation of the clutch is reached, provide a high torque transmission between the now synchronously running drive shaft 2 and the driven shaft 4. The nominal, or design speed, usually, is the operating speed with which the respective tool or machine for which the clutch is connected is designed.
If, due to whatever causes, the driven shaft 4 is suddenly blocked, that is, cannot rotate any more, the centrifugal force, likewise, and equally suddenly and simultaneously drops or disappears. What is left in connecting force between the input shaft 2 and the output shaft 4 is only the relatively small frictional force generated between the input shaft 2 and output shaft 4 due to the engagement pressure of the springs 22 within the centrifugal elements. Feedback of sudden impulses and shocks from the sudden blockage of the shaft 4 to the driving engine through the shaft 2, and, if provided, to all the components coupled thereto, such as gearing, transmission or the like is thereby effectively avoided. The frictional materials of the friction surface 8, for example, which effects transmission of the operating torque, likewise, will not overheat; the engagement between the centrifugal elements 16 and the radial surface 24 is of such low force that any friction surfaces or materials which may be used, will not overheat.
FIG. 3 illustrates another embodiment, in which springs 22', rather than acting in axial direction, act in radial direction on the centrifugal weights 16'. The springs 16' generate a desired, small initial friction connection between the drum-shaped portion 7 of the input clutch part 6' and the weights 16. This force, due to the design of the springs, will be small. It acts, radially, towards the inner friction surface 8' of the driving coupling element 6'. In operation, and as the speed of the driven, output coupling element 14 increases, the initial engagement force due to the springs 22 is superceded by the substantially increased centrifugal forces acting on the centrifugal weights 16' until synchronism, or at least essential synchronism between input shaft 2 and output shaft 4 obtains. The inner ends of the springs 22' can be suitably supported, for example on a sleeve, or on the hub 18 of the clutch part 14.
Centrifugal clutches as described are particularly suitable for core boring elements, for example to make relatively large cylindrical openings in thick reinforced concrete walls. Upon starting, and prior to boring operation, the boring machine is essentially unloaded, so that the output shaft 4 can run essentially freely. An aggregate boring tool, typically in the form of a hollowcylinder can jam during the boring operation within the bore hole, and thus be suddenly blocked; it may, also be blocked by a sudden extra hard aggregate element or the like. The clutch, as described, prevents damage to the driving motor, a transmission coupled thereto, and any other elements at the drive side of the clutch, as well as at the driving and driven sides of the clutch.
By suitable dimensioning, the clutch in accordance with the present invention can also be used as a slip clutch, as known, to permit some slippage upon overloading.
Another particularly important use for the clutch of the present invention is a machine to make cuts in concrete or other aggregate surfaces, for example cuts in roadways or the like. Such cuts are frequently necessary to place cables or conduits to be installed in an existing concrete roadway. FIG. 4 illustrates a movable floor saw and power pack 90 operating as a surface cutting machine. The machine has a chassis 91 with wheels 92. A motor 94 is located within the confines of the chassis 91. Motor 94 has an output shaft 96. A toothed or gear belt 97, or a chain or the like couples rotary force from the motor 94 to a drive pulley 98. The drive pulley 98 is coupled to a driving shaft 112 (FIG. 5) and to a fly wheel 113. A centrifugal clutch 110 is interposed between the fly wheel 113 and the output, or takeup or driven shaft 115. Details of the clutch 110 are shown in FIG. 5. FIG. 4 also illustrates a brake 140, the details of which are likewise illustrated in FIG. 5.
Torque is transferred from the output or driven shaft 115 to a drive pulley, or a drive sprocket 100 of a saw blade 106 by one or more V-belts 99, a sprocket chain, a toothed belt, or any other suitable rotary drive connection.
Preferably, three separate pulleys, or sprocket wheels 115a, 115b, 115c are connected to or form the output or driven shaft 115 of the clutch 110. The different diameter output pulleys permit driving the saw blade 106 at different speeds, given a design running speed of the motor 94.
The clutch 110, illustrated in FIGS. 4 to 6, is particularly suitable for concrete cutters, or other apparatus adapted to drive cutting or tools engageable in aggregate, concrete, rock or the like such as floor saws. Of course, the invention is not limited to such uses, and the clutch can be used also to drive other apparatus.
The centrifugal clutch 110 is a connection element between the driving, or input shaft 112 and the driven or output shaft 115 having pulleys 115a, 115b, 115c coupled thereto to permit engaged, or disengaged connection between the shafts 112 and 115. Intermediate elements can be used to couple the driving shaft 112 to the motor 94, as shown, or other rotation transmitting couplings can be used. Similarly, any suitable rotation transmitting coupling can be used between the respective output pulleys or sprocket wheels 115a, 115b, 115c and the saw blade 106. Tooths, or gear belts, such as belt 99, are preferred.
A drum-shaped or bell-shaped driving coupling element 114 is secured by screws 109 to the fly wheel 113. The drum-shaped clutch element 114 forms a first clutch part. A screw 108 couples a shaft extension 105 to the clutch element 114. The respective parts 105, 113, 114 are, preferably, made as separate parts for ease of manufacture; they could be made as a single, unitary part.
A second clutch part in form of a disc 116, is rotatably supported by a ball bearing 104 on a shoulder of the clutch part 114 and on the shaft extension 105. A needle bearing 103 is located between the output shaft 115 and the shaft extension 105. The output shaft, of course, carries, or includes, or is formed by the sprockets 115a, 115b, 115c. The axes of rotation of the driving shaft 112 and of the driven, or output shaft 115 are coaxial. The three sprockets 115a, 115b, 115c of different diameters may also be constructed as a single unitary element together with the clutch part 116.
In accordance with a feature of the invention, the centrifugal weights 117 are carried by the second, or output, or driven clutch part 116, which, by the ball bearing 104 and the needle bearing 103 is rotatable independently of rotation of the input or driving shaft 112. In this embodiment, three centrifugal weights 117 are provided, spaced from each other by 120° angles. The centrifugal weights 117 are radially slidably or shiftably located on the second clutch part 116. As best seen in FIG. 6, the drum-shaped first clutch part 114 has an axially facing ring-shaped friction layer 118 on radial portion 114b. The centrifugal weights 117 on the clutch part 116 are engaged against the friction layer 118 by spring pressure generated by springs 124 in each of the centrifugal weights 117. The springs 124 provide an axially acting essentially uniform spring force with which the respective weight 117 is pressed against the friction layer 118. The springs 124 are formed as prestressed spiral springs and are seated in a bore 125 of the respective weight 117. The centrifugal weights 117 additionally are provided with radially outwardly located friction pads or strips 120, facing the inner surface 122 of the drum-shaped, or bell-shaped extension 114a of the first coupling part 114. Preferably, the inner surface 122 on axial part 114a of coupling part 114 is also provided with a friction layer. This friction layer has been omitted from the drawing for simplicity of illustration.
Operation
Upon first starting rotation, from stopped condition of the driving shaft 112, the output or driven shaft 115 will be carried along by frictional engagement of the centrifugal weights 117 against the axial ring-shaped friction layer 118 on the disc-shaped portion 114b of the first clutch part 114. There will be slip between the rotary speed of the first clutch part 114, and the second, or output clutch part 116, so that the output or driven shaft 115 will rotate at a lesser speed than the speed of the driving shaft 112. As the speeds of the driving shaft 112, and the driven shaft 115 increase, the centrifugal weights 117 are moved, and then pressed radially outwardly. This engages the friction surface 120 of the weights 117 with the inner surface 122 of the axial extension 114a of the first clutch part 114 or, respectively, with a friction lining at the inner surface thereof, if provided. As the speed of the driven or output shaft 115 increases, the centrifugal force existing on the weights 117 increases with the square of the speed, until there will be, at least essential synchronism between the driving or input shaft and the driven, or output shaft, and full torque transmission is obtained.
The friction force between the friction layer 118 of the clutch part 114 and the centrifugal weights 117 is so dimensioned that the output or driven shaft 115, and any coupling elements and tools, for example the saw blade 106, connected thereto will be carried along, when unloaded, that is, when not doing any machining, or cutting work. Only when the clutch 110 engages, that is, when the centrifugal weights 117 engage radially outwardly against a drum-shaped extension of the first clutch part 114 will full speed and torque transmission be obtained.
If, due to external circumstances, the saw blade 106 (FIG. 4) is stopped, the outward shaft 115 will stop instantaneously and, consequently, the centrifugal force acting on the weights 117 will likewise cease instantaneously. The driving shaft 112 can continue to rotate, however, and only the small start-up friction of the weights 117 against the disc, or ring-shaped friction layer 118 will be subject to heating; this energy can be easily controlled.
The clutch 114 is associated with a brake 140, so that the driven, or output shaft 115 can be braked independently of rotation of the driving, or input shaft 112. The brake 114 has a brake shoe or pad 141 (FIG. 5) acting in axial direction against the outer facing side of the clutch part 116, which is coupled to the output or driven shaft 115. The brake shoe 141 is secured to one end of a double-armed lever 142, which is axially slidable on a shaft 146. The lever 142 can pivot about a bolt 145 secured to a chassis element of the saw 91.
The brake is operated by a manually operable lever 144, which, at its lower end, terminates in a head 139 which has a curved surface 147. The curved surface 147 engages against the upper end of the double-armed lever 142. A spring 143, located on the bolt or shaft 146 engages the other side of the upper arm of the lever 142.
Brake Operation
Upon pivoting of the lever 144 in either direction of, the arrow A, the brake shoe 141 is lifted OFF braking position, in the direction of the arrow B. When the lever is tilted to a substantial extent, two small rollers at the end will hold the lever in the brake-OFF position. FIG. 5 illustrates the lever in brake-ON position, where the spring 143 presses against the lever 142. Both the head 139 of the manually operable lever, as well as the upper portion of the double-armed lever have some play with respect to the shaft or bolt 146 to permit both relatively pivotable as well as sliding movement. Alternatively, the head 139 can have a cam surface and the lever then operates as shown by arrow A' in FIG. 4.
Of course, the centrifugal weights 117 could be constructed similar to the weights 16' (FIG. 3) in which the springs press the centrifugal weights radially against the inner surface 122 of the drum-shaped portion 114a of the first clutch part 114.
The frictional connection between the driving or input shafts 2, 112 and the driven or output shafts 4, 105 can be obtained by a frictional coupling of the respective shafts, or of the clutch parts connected thereto, independently of the centrifugal weights 16, 16', 117, respectively; care must be taken that this frictional coupling is just strong enough to carry along the output shaft upon rotation of the input shaft, so long as the output shaft is unloaded, while permitting slip, and insuring that any generated heat, arising during slip between the input and output shafts can readily dissipated.
The floor saw, or concrete road cutter of FIG. 4 is, preferably, operated this way: first, the motor 94 is started, while the brake 140 is in braking-ON condition. The drive shaft of the motor 24, for example a Diesel motor rotates at idle. The saw blade 106, however, will be stopped because of the engagement of the brake 140. The friction force, for example between the centrifugal elements 16 and surface 24 (FIG. 1) or centrifugal elements 117 and friction layer 118 (FIG. 5) will rub; the heating, however, will be minimal and cooling fins 119 located, for example, at the outer circumference of the axially extending portion of the clutch part 114 can readily dissipate any heat which arises.
When a cut in the bottom surface is to be made, as schematically indicated in FIG. 4, the brake 140 is released by operating manual lever 144 in the direction of the arrow A or, A' this, now, permits initial or preliminary frictional engagement between the clutch members 6, 114 and 14, 116 to become effective. The output shaft and consequently the saw blade 106 will begin to rotate, and as the centrifugal weight elements 16, 117 begin to engage against the axial portion of the first clutch member 6, 114, will accelerate at increasing rate until the speed of the saw blade has reached its operating speed in synchronism with the drive motor. At that point, the saw blade can be introduced into the bottom surface 101 to a selectable depth of cut, in accordance with tilting of chassis 91. If the saw blade for whatever reason, should suddenly jam tight in the cut, the centrifugal clutch immediately, and automatically becomes effective and disconnects power driving torque. The motor, however can continue to run, and the minor small frictional force which originally started the blade turning will not be damaging to either the clutch or the motor. The saw blade, now stopped, can be lifted out of the cut. It will, automatically again begin to rotate until synchronism between motor speed and saw blade is obtained. If, for safety reasons, it is not intended that the saw blade start by itself, it is only necessary to move the braking lever 140 in the ON position shown in FIG. 5, and the clutch will hold the output shaft in the stopped condition, permitting, for example, inspection of the cut, or replacement of the saw blade, without requiring, stopping, and restarting of the motor.
The clutch is specifically suited for transmission of power from a drive engine rated at about one hp up to several hundred hp.
Various changes and modifications may be made and any features described herein may be used with any of the others, within the scope of the inventive concept. | To prevent overloading of a clutch interposed between a driving, or input shaft (2, 112) and a driven, or output shaft (4, 115) upon blockage of the output shaft while continuous rotary power is being transmitted to the input shaft, a plurality of centrifugal weights (16, 117) are located on an output clutch member (14, 116) so that, in case of blockage of the output shaft, centrifugal force will immediately cease and power transmitting engagement between the input and output shafts will be disconnected. In order to permit starting of the clutch, a predetermined small frictional force between an input clutch member (6, 114) coupled to the driving or input shaft (2, 112) and the output clutch member (14, 116) is established, essentially independent of speed, for example under control of springs (22). Since the power connection between the input and output shafts ceases immediately upon blockage of the output shaft, feedback of blocking force, and hence impact loading on a drive motor (14) coupled to the input shaft, and gearing and the like connected thereto is effectively eliminated. The clutch is particularly suitable for use in floor saw--power pack apparatus, power bearing tools, saws, snow blowers or the like, where blockage of the output shaft, unless instantaneously decoupled from a power drive may cause hazards, and/or apparatus damage. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of co-pending U.S. application Ser. No. 12/243,913, filed on Oct. 1, 2008, which claims the benefit of U.S. Provisional Application No. 60/997,334, filed Oct. 1, 2007, which are incorporated by reference herein in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED R&D
[0002] This invention was made with Government support under grant T32 AR007108 to the University of Washington Division of Rheumatology from the National Institutes of Health, and grant MOI-RR-00037 to the University of Washington General Clinical Research Center from the National Institutes of Health.
FIELD OF THE INVENTION
[0003] Aspects of the invention concern ligands that interact with the inhibitory receptor Programmed death 1 (PD-1), which is expressed on activated lymphocytes and regulates tolerance and autoimmunity. Some embodiments relate to, for example, the use of a PD-1 ligand, such PD-L1, to treat or prevent an autoimmune disease, ameliorate the symptoms of an autoimmune disease or indicate the presence or absence (e.g., diagnose) an autoimmune disease, such as systemic lupus erythematosus (SLE).
BACKGROUND
[0004] Autoimmune diseases occur when an organism's immune system fails to recognize some of the organism's own tissues as “self” and attacks them as “foreign.” Normally, self-tolerance is developed early by developmental events within the immune system that prevent the organism's own T cells and B cells from reacting with the organisms own tissues. Major histocompatibility complex (MHC) cell surface proteins help regulate these early immune responses by binding to and presenting processed peptides to T cells.
[0005] This self-tolerance process breaks-down when autoimmune diseases develop. In such diseases, the organism's own tissues and proteins are recognized as “autoantigens” and are attacked by the organism's immune system. For example, multiple sclerosis is believed to be an autoimmune disease, which occurs when the immune system attacks the myelin sheath, whose function is to insulate and protect nerves. It is a progressive disease characterized by demyelination, followed by neuronal and motor function loss. Rheumatoid arthritis (“RA”) is also believed to be an autoimmune disease, which involves chronic inflammation of the synovium in joints with infiltration by activated T cells, macrophages and plasma cells, leading to a progressive destruction of the articular cartilage. It is the most severe form of joint disease. The nature of the autoantigen(s) attacked in rheumatoid arthritis is poorly understood, although collagen type II is a candidate.
[0006] Some believe that multiple sclerosis and rheumatoid arthritis are inherited disorders because these diseases occur more frequently in individuals carrying one or more characteristic MHC class II alleles. For example, inherited susceptibility for rheumatoid arthritis is strongly associated with the MHC class II DRB1 *0401, DRB 1 *0404, or DRB 1 *0405 or the DRB1 *0101 alleles. The human leukocyte antigens (HLA) are found on the surface of cells and help determine the individuality of tissues from different persons. HLA genes are located within the MHC on chromosome 6. The MHC region expresses a number of distinctive classes of molecules in various cells of the body, the genes being, in order of sequence along the chromosome, the Class I, II and III MHC genes. The Class I genes consist of HLA genes, which are further subdivided into A, B and C subregions. The Class II genes are subdivided into the DR, DQ and DP subregions. The MHC-DR molecules are the best known; these occur on the surfaces of antigen presenting cells such as macrophages, dendritic cells of lymphoid tissue and epidermal cells. The Class III MHC products are expressed in various components of the complement system, as well as in some non-immune related cells.
[0007] Another example of an autoimmune disease is Systemic lupus erythematosus (SLE), or lupus, which is a debilitating autoimmune disease characterized by the presence of an array of autoantibodies, including antibodies to double stranded DNA, to nuclear protein antigens and to ribonucleoproteins. SLE affects approximately 1 in 2000 individuals (U.S. 1 in 700 women). The disease primarily affects young women, with a female-to male ratio of approximately 9:1.
[0008] Systemic lupus can affect almost any organ or system of the body. Systemic lupus may include periods in which few, if any, symptoms are evident (“remission”) and other times when the disease becomes more active (“flare”). Most often when people mention “lupus.” they are referring to the systemic form of the disease.
[0009] Corticosteroids are the mainstay in treating systemic autoimmune disorders. Life threatening, severely disabling manifestations of SLE are treated with high doses of glucocorticoids. Undesirable effects of chronic glucocorticoids include an array of prominent adverse effects such as cushingoid habitus , central obesity, hypertension, infection, capillary fragility, hirsutism, accelerated osteoporosis, cataracts, diabetes mellitus, myopathy and psychosis. In addition to corticosteroid toxicity, patient compliance to a dosage regimen also poses a serious problem.
[0010] Cytotoxic agents are also used for controlling active disease, reducing the rate of disease flares, and reducing steroid requirements. Undesirable side effects of the latter include bone marrow suppression, increased infections with opportunistic organisms, irreversible ovarian failure, alopecia and increased risk of malignancy.
[0011] Programmed death 1 (PD-1), an inhibitory receptor expressed on activated lymphocytes, is thought to be involved in autoimmune diseases, such as SLE. PD-1 has two ligands: PD-1 ligand 1 (PD-L1), which is expressed broadly on hematopoietic and parenchymal cells, including pancreatic islet cells; and PD-L2, which is restricted to macrophages and dendritic cells.
[0012] SLE is an inflammatory disease for which to date there is no definitive diagnostic tool, treatment or cure. The disease results in acute and chronic complications. The only current treatments available are palliative, aimed at relieving acute symptoms and preventing chronic complications, often with profound side effects. The need for new detection methods and treatments for autoimmune diseases, such as SLE are manifest.
SUMMARY OF THE INVENTION
[0013] Some embodiments related to method of detecting the presence or absence of an autoimmune disease in a patient comprising:
[0014] identifying a patient that is suspected of having or is at risk of having an autoimmune disease;
[0015] obtaining a biological sample from said patient;
[0016] determining the level of PD-L1 or antibody specific for PD-L1 in said biological sample; and
[0017] correlating the level of PD-L1 or antibody specific for PD-L1 in said biological sample with the presence or absence of an autoimmune disease.
[0018] In some embodiments, the autoimmune disease is selected from the group consisting of multiple sclerosis, Crohn's disease, SLE, Alzheimer's disease, rheumatoid arthritis, psoriatic arthritis, enterogenic spondyloarthropathies, insulin dependent diabetes mellitus, autoimmune hepatitis, thyroiditis, transplant rejection and celiac disease.
[0019] In some embodiments, the autoimmune disease is SLE.
[0020] In some embodiments, the autoimmune disease is rheumatoid arthritis.
[0021] In some embodiments, the biological sample comprises at least one of cells, cell extracts, peripheral blood lymphocytes, serum, plasma and biopsy specimens.
[0022] Some embodiments further comprise providing an antibody that is specific for PD-L1.
[0023] Some embodiments further comprise providing an antibody specific for a to cell surface marker on a monocyte or dendritic
[0024] In some embodiments, the antibody is fluorescently-labeled.
[0025] In some embodiments, the determining step employs flow cytometry.
[0026] Some embodiments relate to a method of distinguishing between the presence of SLE or a bacterial or viral infection in a patient comprising:
[0027] identifying a patient that is suspected of having or is at risk of having an SLE, a bacterial, or viral infection;
[0028] obtaining a biological sample from said patient;
[0029] determining the level of PD-L1 or antibody specific for PD-L1 in said biological sample; and
[0030] correlating the presence, absence, or amount of PD-L1 or antibody specific for PD-L1 in said biological sample with the presence or absence of SLE or a bacterial or viral infection.
[0031] In some embodiments, the biological sample at least one of cells, cell extracts, peripheral blood lymphocytes, serum, plasma and biopsy specimens
[0032] Some embodiments further comprise providing an antibody that is specific for PD-L1.
[0033] Some embodiments further comprise providing an antibody specific for a to cell surface marker on a monocyte or dendritic cell.
[0034] In some embodiments, the antibody is fluorescently-labeled.
[0035] In some embodiments, the determining step employs flow cytometry.
[0036] Some embodiments relate to a method of distinguishing between an active autoimmune disease and an autoimmune disease in remission in a patient comprising the steps of:
[0037] identifying a patient that is suspected of having an active autoimmune disease or an autoimmune disease in remission;
[0038] obtaining a biological sample from said patient;
[0039] determining the level of PD-L1 or antibody specific for PD-L1 in said biological sample; and
[0040] correlating the presence, absence, or amount of PD-L1 or antibody specific for PD-L1 in said biological sample with the presence of an active autoimmune disease or an autoimmune disease in remission.
[0041] In some embodiments, the autoimmune disease is at least one selected from the group consisting of multiple sclerosis, Crohn's disease, SLE, Alzheimer's disease, rheumatoid arthritis, psoriatic arthritis, enterogenic spondyloarthropathies, insulin dependent diabetes mellitus, autoimmune hepatitis, thyroiditis, transplant rejection and celiac disease.
[0042] In some embodiments, the autoimmune disease is SLE.
[0043] In some embodiments, the autoimmune disease is rheumatoid arthritis.
[0044] In some embodiments, the biological sample comprises at least one of cells, cell extracts, peripheral blood lymphocytes, serum, plasma and biopsy specimens.
[0045] Some embodiments further comprise providing an antibody that is specific for PD-L1.
[0046] Some embodiments further comprise providing an antibody specific for a cell surface marker on a monocyte or dendritic cell.
[0047] In some embodiments, the antibody is fluorescently-labeled.
[0048] In some embodiments, the determining step employs flow cytometry.
[0049] Some embodiments relate to a kit for detecting the presence of an autoimmune disease comprising:
[0050] an antibody specific for PD-L1; and
[0051] a correlation of the amount of bound antibody specific for PD-L1 or antibody specific for PD-L1 in a biological sample with the presence or absence of said autoimmune disease.
[0052] In some embodiments, the autoimmune disease is SLE.
[0053] In some embodiments, the autoimmune disease is rheumatoid arthritis.
[0054] Some embodiments relate to a method of treating or preventing an autoimmune disease or treating or preventing the symptoms of an autoimmune disease comprising the steps of:
[0055] identifying a patient in need of such treatment; and
[0056] administering to the patient at least one caspase inhibitor in an amount sufficient to induce or increase PD-L1 expression by the cells of the patient,
[0057] thereby treating or preventing the autoimmune disease or treating or preventing the symptoms of the autoimmune disease.
[0058] In some embodiments, the at least one caspase inhibitor comprises a poly-caspase inhibitor.
[0059] In some embodiments, the at least one caspase inhibitor comprises at least one of Z-WEHD-fmk, Z-VDVAD-fmk, Z-DEVD-fmk, Z-YVAD-fmk, Z-VEID-fmk, Z-IETD-fmk Z-LEHD-fmk, Z-AEVD-fmk, Z-LEED-fmk, Z-VAD-fmk and OPH.
[0060] In some embodiments, the caspase inhibitor is OPH.
[0061] In some embodiments, the autoimmune disease is SLE.
[0062] In some embodiments, the autoimmune disease is rheumatoid arthritis.
[0063] In some embodiments, the administering of the caspase inhibitor to the patient comprises at least one of intravenous, intraperitoneal, inhalation, intramuscular, subcutaneous, nasal and oral administration.
[0064] Some embodiments further comprise the administration of at least one selected from therapeutics targeting HLA molecules, CD18, CD2, CD4, CD28, Fc-gamma 3 receptor, Fc gamma receptor 2a, CTLA4, or TGF-b in an amount sufficient to induce or increase PD-L1 expression by the cells of the patient.
[0065] Some embodiments relate to a method of treating or preventing an autoimmune disease or treating or preventing the symptoms of an autoimmune disease comprising the steps of:
[0066] identifying a patient in need of such treatment;
[0067] removing a biological sample from the patient;
exposing the biological sample to at least one caspase inhibitor ex vivo in an amount sufficient to induce or increase the expression of PD-L1 on the cells in the biological sample;
[0069] washing the cells; and
administering the cells to the patient thereby treating or preventing the autoimmune disease or treating or preventing the symptoms of the autoimmune disease.
[0071] In some embodiments, the at least one caspase inhibitor comprises a poly caspase inhibitor.
[0072] In some embodiments, the biological sample comprises at least one of cells, cell extracts, peripheral blood lymphocytes, serum, plasma and biopsy specimens.
[0073] In some embodiments, the at least one caspase inhibitor comprises at least one of Z-WEHD-fmk, Z-VDVAD-fmk, Z-DEVD-fmk, Z-YVAD-fmk, Z-VEID-fmk, Z-IETD-fmk Z-LEHD-fmk, Z-AEVD-fmk, Z-LEED-fmk, Z-VAD-fmk and OPH.
[0074] In some embodiments, the caspase inhibitor is OPH.
[0075] In some embodiments, the autoimmune disease is SLE.
[0076] In some embodiments, the autoimmune disease is rheumatoid arthritis.
[0077] Some embodiments further comprise the step of exposing biological sample to at least one selected from therapeutics targeting HLA molecules, CD18, CD2, CD4, CD28, Fc-gamma 3 receptor, Fc gamma receptor 2a, CTLA4, or TGF-b in an amount sufficient to induce or increase PD-L1 expression by the cells of the patient.
BRIEF DESCRIPTION OF THE DRAWINGS
[0078] FIG. 1 shows the PD-L1 expression in primary human PBMC. Cells were cultured for one day and live PBMC gated by forward and side scatter. A, PD-L1 is expressed by the CD3 − population in controls and in SLE remission, but not in SLE flare. B, PD-L1 + cells could be divided into 2 groups based on CD14 expression. For A and B, results are representative of PBMC from 17 healthy controls, 12 SLE flare, and 12 SLE remission. C, CD14 lo and CD14 hi cells were further characterized using antibodies to CD11c, CD11b, CD1c, CD8O/CD86, CD45RO, CD83, and HLA-DR. Results are representative of PBMC from 2 controls, 1 SLE flare, and 1 SLE remission.
[0079] FIG. 2 shows APC from subjects with active SLE are deficient in PD-L1. A, PD-L1 is expressed on immature mDC and Mo from healthy children and those in SLE remission, but not from those in SLE flare. Data are representative of PBMC from 17 healthy controls, 12 SLE flare, and 12 SLE remission. B, Mean PD-L1 expression is significantly lower on immature mDC and Mo in active SLE. C, PD-L1 expression correlates with SLE disease activity in individual patients. MFI values were normalized using PD-L1 expression on CD14 − /CD11c − cells for each sample. D, Percent of PD-L1 + APC is decreased in active SLE. For B and D: horizontal bars represent means for 15 controls, 12 SLE flare, and 11 SLE remission; C=Controls, F=SLE flare, R=SLE remission.
[0080] FIG. 3 shows spontaneous PD-L1 expression in APC over time. PBMC from two healthy controls (means+/− standard deviations), one SLE flare, and one SLE remission were cultured for five days and APC identified by surface staining. A, Immature mDC from children with active SLE fail to upregulate PD-L1 on all days. B, Absolute number of immature mDC (open symbols), and number expressing PD-L1 (filled symbols). C, Mo from children with active SLE fail to upregulate PD-L1; although levels appear to rise slightly by day five, there are very low cell numbers remaining in these cultures (see D). D, Absolute number of Mo (open symbols), and number expressing PD-L1 (filled symbols). Timecourse is representative of three independent experiments with similar results, using PBMC from six healthy controls, six SLE flare, and 11 SLE remission.
[0081] FIG. 4 shows that PD-L1 expression is inversely correlated with apoptosis and is upregulated by caspase inhibitors. A, Increased apoptosis in active SLE. PBMC were cultured for one day and stained to identify early (Annexin V + /PI − ) and late (Annexin V + /PI − ) apoptosis. Data shown represent means for PBMC from six controls, six SLE flare, and ten SLE remission. B, OPH reduces apoptosis in PBMC. Data shown represent means for PBMC from two controls, two SLE flare, and one SLE remission. C. OPH treatment significantly increases PD-L1 expression over baseline. Horizontal bars represent mean Mo PD-L1 levels in ten controls, four SLE flare, and seven SLE remission samples; values were normalized as in 2 C. D, Apoptosis is inversely correlated with PD-LI. Percent live PBMC was plotted against Mo PD-L1 expression. Data shown are representative of two independent experiments.
[0082] FIG. 5 shows that other APC surface markers are not globally upregulated by caspase inhibitors. A, OPH increases PD-L1 and increases the number of CD14 int among PD-L1 + PBMC. B, OPH does not increase other APC surface markers. Data shown are representative of PBMC from two healthy controls, one SLE flare, and one SLE remission. C, APC express very little PD-L2 after one day of culture. Data are representative of PBMC from three controls and one SLE remission. D, PD-L2 expression is associated with CD14 levels, but is not increased by OPH, Z-VAD, or DMSO control through four days of culture. Bars represent means+/− standard deviations of PD-L2 expression in two healthy controls.
[0083] FIG. 6 shows that potential cleavage sites for caspases 1-9 fall between PD-L1 amino acids 70-180. Caspases are listed in order of greatest likelihood of cleavage at that site based on correlation with their known consensus recognition sequences.
[0084] FIG. 7 shows the costimulatory potential of SLE flare APC could be normalized by inhibition of caspases PBMC were cultured for one day and stained for the costimulatory molecules C080, CD86, and PD-L1. CD80/86 levels are similar in control and SLE flare APC, but SLE flare cells lack concurrent PD-L1 expression. Treatment of PBMC with OPH increased PD-L1 levels in control cells and restored normal levels of PD-L1 in SLE flare cells. PBMC from a second healthy child and from a patient in SLE remission behaved the same as the normal control.
[0085] FIG. 8 shows the cytokine expression by T cells in autologous culture. Bars represent the percent of each cell type expressing cytokines (mean+/−S.E.).
[0086] FIG. 9 shows the levels of caspase activity in PBMC from children with and without SLE. Symbols denote differences between populations: **p<0.05, demonstrating a significant difference between SLE and controls; *p<0.071, demonstrating a trend toward significance between SLE and controls.
[0087] FIG. 10 shows the effect of caspase inhibitors on PBMC death and apoptosis. Treated cells were assayed for cell death and apoptosis using Annexin V and PI, as well as stained for cell-surface expression of PD-L1 on APC. Note: sample results for only one set of control cells treated with OPH and Z-VAD-fmk are shown here, but studies were performed using both poly- and specific caspase inhibitors on multiple sets of PBMC.
[0088] FIG. 11 shows the effect of specific caspase inhibitors on PD-L1 expression in mDC. This graph shows the PD-L1 quantitation results for one set of control mDC treated with various inhibitors.
[0089] FIG. 12 shows the PD-L1 expression in Mo under pro- and anti-apoptotic culture conditions. Normal PBMC were cultured in standard medium containing serum (med), medium without serum (serum-) to increase apoptosis, or in medium containing 50 uM of polycaspase inhibitor (OPH) to decrease apoptosis. Bars reflect the mean values for Mo from two healthy individuals; left graph: PD-L1 MFI; right graph: percent of Mo expressing PD-L1.
[0090] FIG. 13 shows PD-L1 protein is deficient on APC during SU flare, but not during remission, (A) PBMC were cultured for 1 day and APC subsets identified. (B) PD-L1 expression on both mDC and Mo was reduced during SLE flare, but not during remission. (C) CD1c staining demonstrated that PD-L1 expression in CD14 lo CD11c +0 cells was enriched on Type I immature mDC. (D) PD-L1 levels on mDC (upper graph) and Mo (lower graph) from 15 controls, 12 SLE flare and 14 SLE remission. Circles represent individual PD-L1 values and bars represent the mean MFI (±1 s.d.) for each group. For SLE flare mDC, *P<6.5×10 −3 compared with controls; *P<2.5×10 −2 compared with remission. For SLE flare Mo, *P<1.8×10 −4 compared with controls; *P<2.4×10 −6 compared with remission. For SLE remission Mo, *P<3.4×10 −3 compared with controls. (E) PD-L1 expression on mDC and Mo was normalized to background levels using the PD-L1 MFI of CD 14 − CD11c − cells as the denominator for each sample. For SLE Clare mDC, *P<4.1×10 −3 compared with controls; *P<2.1×10 −2 compared with remission. For SLE flare Mo, *P<2.0×10 −8 compared with controls; *P<1.1×10 −8 compared with remission. (F) SLE flare patients exhibited a lower percentage of PD-L1 APC (mDC, upper graph and Mo, lower graph). For SLE flare mDC, *P<4.2×10 −3 compared with controls. For SLE flare Mo, *P<1.1×10 −6 compared with controls; *P<4.0×10 −8 compared with remission. (G) Mo PD-L1 values from (E) were graphed for patients with serial blood samples; shaded area denoted the ‘normal range’ of Mo PD-L1 expression observed in healthy controls (mean±1 s.d.).
[0091] FIG. 14 shows lupus flare APC express positive co-stimulatory molecules. PBMC were cultured for 1 day and gated for APC as given earlier. Compared with control cells (top row), SLE flare APC (middle row) lacked PD-L1 and the CD80/86 hi subset of mDC. In contrast, SLE remission cells (bottom row) expressed both PD-L1 and CD80/86 in a pattern similar to that of controls (numbers in each graph represent the percentage of cells in each quadrant). Results are representative of two separate experiments using PBMC from three healthy controls, two SLE flare and two SLE remission.
[0092] FIG. 15 shows PD-L1 expression on SLE Mo and mDC can be induced by CD4+ T cells from a healthy donor. CD3+CD4+ T lymphocytes were isolated from healthy PBMC by florescence activated cell sorting and added to total PBMC from an SLE patient with active disease. After one day in culture, PD-L1 expression on CD11c+CD14+Mo and CD11c+CD1410 mDC was assayed by flow cytometry.
[0093] FIG. 16 shows PD-L1 expression is induced in isolated mDC and Mo to the same extent as in mixed PBMC cultures. CD11c+ cells were isolated by FACS to >99% then cultured over night in parallel with unfractionated PBMC from the same subjects. The numbers represent percent of Mo expressing PD-L1.
DETAILED DESCRIPTION OF THE INVENTION
[0094] Several embodiments described herein are related to the identification, amelioration, and/or treatment of a wide variety of autoimmune or immune related diseases or disorders including, for example, multiple sclerosis, Crohn's disease, SLE, Alzheimer's disease, rheumatoid arthritis, psoriatic arthritis, enterogenic spondyloarthropathies, insulin dependent diabetes mellitus, autoimmune hepatitis, thyroiditis, transplant rejection and celiac disease.
[0095] Some embodiments concern the use of a PD-L1 leukocyte expression assay to identify the presence, absence, or progression of an autoimmune disease, for example. More embodiments relate to the use of a PD-L1 agonist or ligand to ameliorate or treat an autoimmune disease. Some embodiments concern methods, wherein a PD-L1 ligand is provided to a patient that has been identified as having an autoimmune disease, such as SLE, and the general health or welfare of the patient is improved during the course of treatment. Optionally, the improvement in said patient is monitored or measured before, during, or after administration of said PD-L1 ligand using conventional clinical evaluation or observation, analysis of diagnostic markers for the disease, or by using one or more of the diagnostic techniques described herein.
[0096] Active SLE is associated with failure of antigen presenting cells to upregulate programmed cell death ligand-1. Antigen presenting cells (APC) maintain peripheral T cell tolerance in part via expression of negative costimulatory molecules such as programmed cell death ligand-1 (PD-L1). APC in peripheral blood, including CD14+/CD11c+ monocytes (Mo) and CD14−/CD11c+ myeloid dendritic cells (mDC), have been implicated in the pathogenesis of SLE. Patients with active disease generally have decreased numbers of Mo in peripheral blood mononuclear cells, and their APC generally fails to upregulate PD-L1 appropriately when cultured ex vivo, as measured by flow cytometry. APC from healthy individuals or SLE patients in remission tend to upregulate PD-L1 surface expression by day one, with peak expression on day two or three, and declining expression through day six, all in the absence of exogenously-added stimuli. Therefore, failure of APC to upregulate PD-L1 correlates with abnormal T lymphocyte regulation and loss of peripheral tolerance in SLE.
[0097] Programmed death ligand-1 (PD-L1; also known as B7-H1/CD274), is a B7 family glycoprotein inducibly expressed on many hematopoietic and parenchymal cells in response to inflammatory stimuli. It regulates immune tolerance by binding to the programmed death-1 (PD-1) receptor on lymphocytes, causing suppression of T-effector function, and permissiveness of regulatory T-cell function. PD-L1 may also suppress T-cell activation by signaling through the B7-1 receptor. Although mRNA for PD-L1 can be found in many healthy human tissues, baseline protein expression appears to be limited to cells of monocytic origin. Both myeloid dendritic cells (mDC) and monocytes (Mo) express PD-L1 protein, and anti-PD-L1 antibody increases the stimulatory capacity of mature and immature DCs for T-effector cells. Endogenous or transgene-driven expression of PD-L1 on antigenpresenting DCs leads to diminished T-cell reactivity in vitro and in vivo, as demonstrated in murine models of autoimmunity. The importance of PD-L1 in self-tolerance has also been demonstrated in experimental animals in which blockade or absence of the PD-L1:PD-1 pathway results in various forms of autoimmune disease, including a spontaneous lupus-like glomerulonephritis in C57BL/6 mice.
[0098] The receptor for PD-L1 is shared by a second ligand, PD-L2, (B7-DC/CD273), which can also inhibit T-cell activation, but is less widely expressed and appears to play some non-redundant roles in self-tolerance. DNA polymorphisms in the gene for the shared PD-1 receptor have been linked to SLE susceptibility in some populations of adults and children; however, T-cell expression of PD-1 protein has not been found to differ significantly between SLE patients and controls. In contrast to the PD-1 gene studies, genetic polymorphisms in PD-L1 did not appear to be linked to SLE. However, both immature mDC and Mo from children with SLE failed to up-regulate PD-L1 normally, and this deficiency was associated with increased disease activity, indicating an important role for this negative co-stimulator in the pathogenesis of SLE.
[0099] As discussed above, PD-L1 on antigen presenting cells binds to PD-1 on T lymphocytes, and regulates their activity. Animals without PD-1 develop an autoimmune disease similar to SLE, with T lymphocytes reacting to self proteins. Some embodiments relate to the discovery that patients with active SLE express almost no PD-L1 on their antigen presenting cells. The same patients, when their disease is in remission, express PD-L1.
[0100] Accordingly, some embodiments concern methods to identify the presence, absence, or progression of an autoimmune disease, such as SLE, in a subject that has been identified as having an autoimmune disease or a subject identified as being at risk for developing an autoimmune disease, wherein the presence, absence, or amount of PD-L1 in a biological sample from said subject is analyzed, detected, or determined. In some embodiments, such assays are performed by staining peripheral blood lymphocytes obtained from a subject with a fluorescence-labeled antibody specific for PD-L1, along with antibodies to cell surface markers for monocytes and dendritic cells (CD11c and CD14). Optionally, the frequency of cells expressing PD-L1 or the amount of PD-L1 on a subject's peripheral blood lymphocytes in the sample is detected using flow cytometry, ELISA, or other immunological detection techniques. Thus, some embodiments include methods to identify the presence, absence, or likelihood to acquire an autoimmune disease, such as SLE, wherein a molecule that specifically binds to PD-L1, such as an antibody, binding partner for PD-L1, or a binding fragment thereof (e.g., an identifiable ligand for PD-L1), is contacted with a biological sample obtained from a patient (e.g., blood) or a component isolated therefrom (e.g., a peripheral blood lymphocytes) for a time sufficient to create a PD-L1/binding partner complex and the presence, absence, or amount of said PD-L1/antibody or binding partner complex is measured or detected, which then indicates the presence, absence, or likelihood to acquire the autoimmune disease. The assays described above may be used to assess the efficacy of a treatment regimen or the progression of a treatment protocol or the progression of an autoimmune disease. Other embodiments relate to methods to identify individuals that are at risk for developing an autoimmune disease, or individuals that are at risk for relapse of a preexisting autoimmune disease.
[0101] The identifiable ligand for PD-L1 or PD-L1 binding partner may be an antibody (e.g., a monoclonal antibody or a polyclonal antibody, which may be humanized or modified) or a fragment of an antibody that binds to a PD-L1 antigen. Polyclonal and monoclonal antibodies may be prepared by conventional techniques. See, for example, Monoclonal Antibodies, Hybridomas: A New Dimension in Biological Analyses , Kennet et al. (eds), Plenum Press, New York (1980); and Antibodies: A Laboratory Manual , Harlow and Land (eds.), Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., (1988). Antigen-binding fragments of such antibodies, which may be produced using conventional techniques, are also encompassed by the present invention. Examples of such fragments include, but are not limited to, Fab, F(ab′), and F(ab′) 2 , fragments. Antibody fragments and derivatives produced by genetic engineering techniques are also provided. The monoclonal antibodies may be chimeric antibodies, e.g., humanized versions of murine monoclonal antibodies. Such humanized antibodies may be prepared by known techniques. In some embodiments, a humanized monoclonal antibody comprises the variable region of a murine antibody (or just the antigen binding site thereof) and a constant region derived from a human antibody. Alternatively, a humanized antibody fragment may comprise the antigen binding site of a murine monoclonal antibody and a variable region fragment (lacking the antigen-binding site) derived from a human antibody. Procedures for the production of chimeric and further engineered monoclonal antibodies include those described in Riechmann et al. ( Nature 332:323, 1988), Liu et al. ( PNAS 84:3439, 1987), Larrick et al. ( Bio/Technology 7:934, 1989), and Winter and Harris ( TIPS 14:139, May, 1993).
[0102] The identifiable PD-L1 ligand or binding partner for PD-L1 may also be a peptide or peptidomimetic that binds to PD-L1. Peptides and peptidomimetics that bind to PD-L1 can be identified using computer modeling of the binding regions of antibodies that interact with PD-L1 and identifying peptides and peptidomimetics with similar structures. Peptides and peptidomimetics that bind to PD-L1 can also be identified by screening detectably labeled PD-L1 against libraries of peptides and peptidomimetics and determining the presence of detectably labeled PD-L1/binding partner complexes. Alternatively, detectably labeled peptides and peptidomimetics can be screened against PD-L1 and the presence of detectably labeled binding partner/PD-L1 complexes can be identified. Preferably, the ligands for PD-L1 (e.g., an antibody, a PD-L1 antigen-binding fragment thereof or PD-L1 ligand) is detectably labeled. The label may be colorimetric, fluorescent, a radioisotope, or a metal.
[0103] More embodiments relate to the use of PD-L1 or a nucleic acid encoding PD-L1 as a therapeutic to regulate T lymphocytes in patients suffering from an autoimmune disease, such as SLE. In some embodiments, for example, PD-L1 is provided to or administered to a patient that has been identified as having an autoimmune disease, such as SLE, and the presence, absence, or progression of the autoimmune disease or a marker thereof is measured or detected using clinical evaluation or diagnostic assay. In more embodiments, a nucleic acid encoding PD-L1 (e.g., DNA or RNA), preferably a nucleic acid that has been codon optimized for expression in humans is provided or administered to a patient that has been identified as having an autoimmune disease, such as SLE, and the presence, absence, or progression of the autoimmune disease or a marker thereof is measured or detected using clinical evaluation or diagnostic assay.
[0104] Some additional embodiments relate to methods of inducing or increasing PD-L1 expression in patients. In some embodiments, for example, caspase inhibitors can be administered to a patient with autoimmune disease in order to induce or increase PD-L1 expression in the patient, thereby treating or preventing the autoimmune disease or ameliorating the symptoms of the autoimmune disease. Such inducement or increase can be achieved by administering to the patient an amount of at least one caspase inhibitor in an amount sufficient to induce or cause an increase in the expression of PD-L1 by a patient's cells. In some embodiments, the caspase inhibitors can be combined with one or more therapeutic capable of treating or preventing the autoimmune disease or ameliorating the symptoms of the autoimmune disease. In certain embodiments, the caspase inhibitors can be specific caspase inhibitors, pan caspase inhibitors, poly-caspase inhibitors or a combination thereof. In some embodiments, the caspase inhibitors are, for example, at least one of Z-WEHD-fmk, Z-VDVAD-fmk, Z-DEVD-fmk, Z-YVAD-fmk, Z-VEID-fmk, Z-IETD-fmk Z-LEHD-fmk, Z-AEVD-fmk, Z-LEED-fmk, Z-VAD-fmk and OPH. However, the current embodiments are not limited to such examples and encompass any pharmaceutically acceptable caspase inhibitor.
[0105] More embodiments relate to methods of inducing or increasing PD-L1 expression by the cells of a patient by removing cells from the patient and exposing the cells to at least one caspase inhibitor ex vivo in order to induce or increase the expression of PD-L1 on the cells, washing the cells and then administering the cells to a patient.
[0106] In some embodiments, an additional therapeutic can be combined with at least one caspase inhibitor that is either administered to the patient in vivo or exposed to cells of the patient ex vivo to induce or increase PD-L1 expression by the cells. Examples of such additional therapeutics include therapeutics targeting HLA molecules, CD18, CD2, CD4, CD28, Fc-gamma 3 receptor, Fc gamma receptor 2a, CTLA4, or TGF-b.
Example 1
PD-L1 Protein Levels Downmodulated in Control Mo Using Specific siRNA
[0107] In this model, siRNA technology was used to diminish mRNA for PD-L1. Normal PBMC were obtained from healthy volunteers and frozen in liquid nitrogen. At the time of experiments, cells were thawed, washed, and diluted to 1−2×10 6 cells/ml in culture medium consisting of RPMI 1640 supplemented with L-glutamine (CellGro), 10% heat-inactivated A/B human serum, 1% penicillin/streptomycin (CellGro), and 0.1% beta-mercaptoethanol. Cells were plated in round-bottom 96-well plates (Corning Costar) and incubated at 37° C. in a humidified cell chamber with 5% CO 2 . After a four-hour rest period, total PBMC were incubated with Mo nucleofection buffer (Amaxa) plus specific anti-human PD-L1 siRNA or control siRNA (se-39699. Santa Cruz Biotechnology, Inc.) and nucleofected as per the manufacturer's protocol (Amaxa).
[0108] PBMC were returned to the incubator and cell surface PD-L1 levels determined by flow cytometry 24 hours later. Cells were surface-stained using various fluorochrome- or biotin-conjugated monoclonal antibodies, including: anti-CD3, anti-PD-L1 (eBioscience), anti-CD 11c, and anti-CD14, (Pharmingen/BD Biosciences), with isotype-matched, fluorochrome-/biotin-labeled irrelevant monoclonal antibodies as controls. Some cells were cultured for longer time periods to assay the level of intracellular proteins (cytokines and Foxp3). To determine intracellular caspase activity, selected cultures were incubated with a cell-permeant fluorochrome-derivative of the appropriate caspase inhibitor for each caspase under investigation.
[0109] Prior to staining for intracellular cytokines, cells were restimulated for four hours with 1 ug/ml phorbol myristate acetate (PMA) plus 14 uM ionomycin, in the presence of GolgiStop (BD Biosciences) to prevent cytokine secretion. Cells were permeabilized with the appropriate proprietary buffers according to the manufacturer's protocols (BD Biosciences, eBioscience, or BioLegend), and intracellular cytokine production was assayed using fluorochrome-conjugated monoclonal antibodies to interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), and interleukin-17 (IL-17) (Pharmingen/BD Biosciences). Prior to staining for Foxp3 (BioLegend), cells were permeabilized, but not restimulated, All samples were blocked using 0.5% human serum and anti-FcR antibody (Miltenyi) during staining. Dead cells were excluded from the analysis using a dead cell marker dye. After staining, PBMC were fixed using 2% paraformaldehyde in PBS after preliminary experiments indicated no effect of cell fixation on expression levels of PD-L1 or other surface markers. Flow cytometry was performed using an LSR II cytometer (Becton Dickinson), and the data were analyzed using FlowJo software (Macintosh Version 6.3). Mo and immature myeloid DC (mDC) were identified using surface markers characteristic of each cell type. Results were compared between populations using Student's I-test, and significance assigned where p<0.05.
[0110] In the siRNA studies it was confirmed that the distribution of leukocyte subtypes in PBMC were not altered by this experimental manipulation (Table I), and that the number of cells expressing PD-L1 also remained unchanged in these cultures (Table II). However, expression of PD-L1 protein on Mo and mDC was reduced by 24 hours (Table III), while the levels PD-L1 of on other PBMC subsets remained unchanged.
[0000]
TABLE I
Table I. Leukocyte subsets in nucleofected PBMC from two healthy controls.
Ancestry Subset
% Live of
% CD14+ of
% CD1c+ of
% CD11c+ of
% CD3+ of
Value Type For
Lymphs
Live
Live
Live
Live
Mbr No Stain Control
99
0
0.02
0.03
0
Mbr IgG Contral Control
90
1.3
3.9
29
58
NOP511(2) d1 PDL1 High
73
4.2
2.7
25
52
Control siRNA
NOP511(2) d1 PDL1 Low
76
5.4
3.2
29
54
PDL1 siRNA
NOP511(2) d1 PDL1 High
74
5.5
3.5
33
54
PDL1 siRNA
NOP505A(2) d1 PDL1 High
66
1.3
2.3
27
59
Control siRNA
NOP505A(2) d1 PDL1 Low
69
2.3
3.3
27
56
PDL1 siRNA
NOP505A(2) d1 PDL1 High
63
1.3
3.4
29
56
PDL1 siRNA
NOP505A(2) d1 PDL1 GFP
75
2.5
2.7
27
57
vector no zap
[0111] PBMC from two healthy individuals were subjected to nucleofection using control siRNA or two different concentrations of PD-L1 siRNA and results compared with those in normucleofected control cultures to confirm that specific leukocyte subsets were not preferentially destroyed by this manipulation. Numbers represent percent of each cell type remaining in culture at the end of day one.
[0000]
TABLE II
Table II. Percent of each leukocyte subset expressing PD-L1 after nucleofection.
Ancestry Subset
% PDL1+ of
% PDL1+ of
% PDL1+ of
% PDL1+ of
% PDL1+ of
Value Type For
Live
CD14+
CD1c+
CD11c+
CD3+
Mbr No Stain Control
0
*
0
0
*
Mbr IgG Control Control
0.8
0.4
1.7
26
0.8
NOP511(2) d1 PDL1 High
7.2
97
8.7
15
4
Control siRNA
NOP511(2) d1 PDL1 Low
6.7
91
7.5
16
2.1
PDL1 siRNA
NOP511(2) d1 PDL1 High
7.2
91
7.8
17
2.7
PDL1 siRNA
NOP505A(2) d1 PDL1 High
3.2
75
7.6
7.3
2.2
Control siRNA
NOP505A(2) d1 PDL1 Low
3.7
64
2.7
8.9
2.4
PDL1 siRNA
NOP505A(2) d1 PDL1 High
5.1
67
7.2
11
4.6
PDL1 siRNA
NOP505A(2) d1 PDL1 GFP
3
61
9
8.1
1.9
vector no zap
[0112] PBMC from two healthy individuals were subjected to nucleofection using control siRNA or two different concentrations of PD-L1 siRNA and results compared with those in normucleofected control cultures to confirm that the percent of cells in each specific leukocyte subset was not altered by this manipulation. Numbers represent percent of each cell type expressing PD-L1 in culture at the end of day one.
[0000]
TABLE III
Table III. PD-L1 expression in nucleofected leukocyte subsets.
Ancestry Subset
PDL % MF1 of
PDL1 MF1 of
PDL1 MF1 of
PDL1 MF1 of
Value Type For
CD14+
CD1c+
CD11c+
CD3+
Mbr No Stain Control
*
298
113
*
Mbr IgG Control Control
151
240
325
172
NOP511(2) d1 PDL1 High
13578
775
2398
557
Control siRNA
NOP511(2) d1 PDL1 Low
7699
621
1741
410
PDL1 siRNA
NOP511(2) d1 PDL1 High
7013
690
1608
299
PDL1 siRNA
NOP505A(2) d1 PDL1 High
5405
635
864
322
Control siRNA
NOP505A(2) d1 PDL1 Low
3108
255
599
332
PDL1 siRNA
NOP505A(2) d1 PDL1 High
3512
420
675
434
PDL1 siRNA
NOP505A(2) d1 PDL1 GFP
3582
535
640
308
vector no zap
[0113] PBMC from two healthy individuals were subjected to nucleofection using control siRNA or two different concentrations of PD-L1 siRNA and results were compared with those in normucleofected control cultures to confirm that PD-L1 was specifically downmodulated in CD14+ Mo and mDC, while other cell types were unaffected. Numbers represent mean fluorescence intensity (MFI) of PD-L1 in of each cell type under various treatment conditions at the end of day one. Symbols represent **p<5×10 −5 , # p<0.033, and *p<5×10 −4 .
[0114] In order to allow interaction of APC with autologous T cells, a culture of each PBMC sample was incubated for another four days. At the end of this time, PBMC were assessed for intracellular cytokine production in T lymphocytes as well as for expression levels of the regulatory T cell marker, Foxp3. Although Mo treated with siRNA expressed significantly lower amounts of surface PD-L1, production of IFN-γ. TNF-α, and IL-17, and the level of intracellular Foxp3 expression remained unchanged in T cells. The T cells examined in these studies were autologous cells, incubated and treated concurrently with the APC, thus (1) limiting the number and magnitude of the T lymphocyte response as compared to an allogeneic reaction, and (2) allowing the possibility that T cells in these cultures may have been affected by the nucleofection process itself, even though preliminary studies gave no indication of adverse effects on T cell survival or function. These experiments showed that the distribution of leukocyte subtypes in PBMC were not altered by this experimental manipulation (Table I), and that that the number of cells expressing PD-L1 also remained unchanged in these cultures (Table II). Neither of these parameters was altered, however, expression of PD-L1 protein on Mo and mDC were reduced by 24 hours (Table III and FIG. 1 ), while the levels PD-L1 of on other PBMC subsets remained unchanged.
Example 2
PD-L1 Protein Levels were Increased in APC by Inhibition of Caspase Activity
[0115] PBMC were cultured as above and a duplicate well of each sample treated with 50 uM OPH. PD-L1 upregulation on APC was confirmed in these cultures, and an aliquot of each sample was incubated further in order to allow interaction of APC with autologous T cells in culture. Three days later, the cells were fixed and permeabilized, and the T lymphocytes were assayed for intracellular expression of the regulatory T cell protein, Foxp3.
[0116] It was found that OPH increased PD-L1 expression on the surface of both Mo and mDC at day one. Identification of endogenous Treg in the PBMC cultures using Foxp3 protein revealed not only fewer Treg in lupus PBMC, but also less Foxp3 protein per cell, indicating that development and/or survival of Treg was abnormal in SLE. Although cultures treated with OPH expressed significantly higher amounts of PD-L1 on the surface of APC, the level of Foxp3 expression in both healthy control and SLE cultures remained unchanged, both with respect to Foxp3 MFI and to the number of CD4 + cells expressing Foxp3. These experiments showed that diminished PD-L1 levels on lupus APC directly affect Treg development.
Example 3
PD-L1 Signaling was Inhibited Using Anti-PD-1 Antibodies
[0117] Soluble anti-PD-1 antibody was utilized to block PD-L1 signaling in autologous PBMC cultures, and the effect on T cell cytokine production was evaluated after five days of incubation. It was found that soluble anti-PD-1 antibody at this concentration did not significantly affect intracellular production of IFN-γ, TNF-α, or IL-17 in T cells (see FIG. 8 ), but this may have also been due in part to the fact that the T cells were minimally stimulated, as they were responding to autologous APC. These experiments did demonstrate the ability to detect small changes in T lymphocyte cytokine production among total PBMC. PBMC from eight healthy individuals were incubated with autologous APC in the presence of soluble control IgG or anti-PD-1 antibody to assess the effect of blocking PD-L1 signaling on T cell cytokine production. After five days, CD4 and CD8 T cells were identified and assayed for the presence or absence of intracellular cytokines. These experiments showed that soluble anti-PD-1 antibody at this concentration did not significantly affect intracellular production of IFN-γ, TNF-α, or IL-17 in T cells.
Example 4
Caspase Activity Levels were Measured in APC from Children with and without SLE
[0118] Cells were cultured as above, and PBMC were stained with Annexin V and propidium iodide (PI) (both from Becton Dickinson) to identify both dead and dying cells. After apoptotic cells were omitted from our analyses, the intracellular levels of caspases in living leukocytes were quantitated using fluorochrome derivatives of known caspase inhibitors which only bind at the active site (Immunochemistry Techologies, Inc.), thus revealing both caspase identity and activity level simultaneously in each individual cell. Using PBMC from five controls and two children with SLE, the mean fluorescence intensity (MFI) for each active caspase was measured, and results between controls and SLE compared using a 2-tailed t-test. Significance was assigned where p<0.05.
[0119] Surprisingly, for all of the eight caspases tested, it was found that enzyme activity levels in non-apoptotic cells exhibited the pattern: Mo>mDC>other PBMC, indicating an important role for caspases in normal Mo function (see FIG. 9 ). However, when comparing control Mo to SLE Mo, it was found that among individual caspases tested, only the activity of caspase-13 was significantly different between the two groups. The activity levels of caspases 1, 2, and 9 also appeared to be higher among SLE Mo. These experiments showed the baseline expression of caspases and their activity, level in human cells.
Example 5
Individual Caspases were Inhibited and APC Tested for Expression of PD-L1
[0120] This study examined the direct contribution of each caspase to the regulation of PD-L1 expression in vitro. Amino acids 70-180 of PD-L1 are shown in FIG. 10 , with potential caspase cleavage sites marked by the four arrows. Caspase numbers are listed above each site in order of likelihood of cleavage.
[0121] In order to determine which caspase (or caspases) is responsible for downmodulation of PD-L1 during active lupus, the effects of specific caspase inhibitors on PD-L1 expression in human APC were tested (Table IV). Control and SLE PBMC were incubated for one day in the presence of the individual caspase inhibitors at doses ranging from 10 uM to 50 uM (R&D Systems), with the appropriate level of DMSO as the carrier control (0.5% final concentration). Treated cells were assayed for cell death and apoptosis using Annexin V and PI (example shown in FIG. 4 ), as well as stained for cell-surface expression of PD-L1 on APC.
[0000]
TABLE IV
Specific caspase inhibitors and their targets.
Inhibitor
Caspase target
Z-WEHD-fmk
1
Z-VDVAD-fmk
2
Z-DEVD-fmk
3 (and 7)
Z-YVAD-fmk
4
Z-VEID-fmk
6
Z-IETD-fmk
8
Z-LEHD-fmk
9
Z-AEVD-fmk
10
Z-LEED-fmk
13
Z-VAD-fmk or OPH
Polycaspase inhibitor
[0122] The inhibitors enter living cells and bind irreversibly at the caspase active sites, preventing further proteolytic activity by the enzyme. After incubation with caspase inhibitors, PBMC were gated by forward and side scatter and analyzed for percent cell death and apoptosis using Annexin V and PI (see FIG. 10 ). It was found that treatment of PBMC with the specific caspase inhibitors was less potent for reducing cell death and apoptosis than the poly-caspase inhibitors, OPH and Z-VAD-fmk. It was also found that treatment of PBMC with low doses of the caspase-specific inhibitors (10-25 uM) did not affect PD-L1 expression by APC. However, higher doses of some caspase-specific inhibitors (50 uM), did alter PD-L1 levels, both in Mo and mDC (example shown in FIG. 11 ). Normal PBMC were incubated in medium with or without various caspase inhibitors, and PD-L1 protein levels assessed at day one. This graph shows the PD-L1 quantitation results for one set of control mDC treated with various inhibitors. Notably, using Method 1 above, it was observed that an elevation of active caspases 1, 2, 9, and 13 in SLE cells, with statistical significance demonstrated for caspase 13. In this set of experiments to determine the effect of these caspases on PD-L1 expression, we found that caspase-13 seemed to figure prominently in PD-L1 regulation (see Chart 6, under Z-LEED-fmk), confirming the usefulness of this multifaceted approach. Although the caspase-3 inhibitor (Z-DEVD-fmk) also greatly increased PD-L1 levels, caspase-3 acts as a master regulator of the caspase cascade and therefore it is not yet clear whether this enzyme acts directly on PD-L1 or via another caspase. Accordingly, these experiments demonstrate the direct contribution of each caspase to the regulation of PD-L1 expression in vitro.
Example 6
Downregulation of PD-L1 Protein Expression in Normal Mo by Induction of Apoptosis
[0123] Healthy human PBMC were cultured and half of each sample were exposed to pro-apoptotic conditions—in this case, to withdrawal of serum from the culture medium. After 24 hours, cells were surface stained as above to identify Mo and to measure PD-L1 protein expression. It was found that among normal PBMC cultured in the absence of serum, PD-L1 protein levels dropped dramatically by 24 hours, as did the number of Mo expressing PD-L1 (Chart 7). The average PD-L1 MFI on Mo was reduced by more than half, while the percent of Mo expressing this negative costimulator dropped by one third. This PD-L1 profile observed in the context of serum withdrawal was remarkably similar to that obtained using cells from patients with active SLE, indicating that the loss of PD-L1 in lupus APC is indeed due to heightened caspase activity in these cells.
[0124] The effect of various caspase inhibitors on PD-L1 expression in normal APC was also tested, as healthy cells can be made “lupus-like” by subjecting them to pro-apoptotic conditions (see FIG. 12 ). Normal PBMC were cultured in standard medium containing serum (med), medium without serum (serum-) to increase apoptosis, or in medium containing 50 uM of poly-caspase inhibitor (OPH) to decrease apoptosis. This system was used to test the effects of other pro-apoptotic conditions on caspase activation and PD-L1 expression, to determine if different apoptotic signals regulate PD-L1 differently. Such conditions include: UV irradiation, Fas:FasL signaling, and heat shock, as well as testing the direct effects of SLE serum on APC, as it has very recently been demonstrated that incubation of healthy leukocytes with lupus serum induces “classical” caspase-dependent apoptosis. These experiments provided evidence that the upregulation of caspase activity in normal cells should also lead to the downmodulation of PD-L1.
Example 7
Direct Cleavage of Human PD-L1 Protein In Vitro
[0125] As shown above, there exist significant differences in caspase activity between control and SLE APC, as well the PD-L1-enhancing effects of polycaspase inhibitors on human PBMC. These findings indicate that PD-L1 is directly cleaved by one or more active caspases.
[0126] Purified PD-L1 and control protein targets are incubated with individual caspases in the appropriate buffers under the conditions specified by the manufacturer. The resultant peptide products are fractionated by SDS-PAGE. Protein fragments are identified by size and gel-purified for further identification. Any molecules of interest are sequenced to confirm or refute potential PD-L1 caspase cleavage sites. Caspases of interest identified in these experiments are combined with other caspases in PD-L1 cleavage experiments, to determine whether a sequential or concurrent proteolysis of PD-L1 may occur during downmodulation of PD-L1 in living cells. We found that several caspases are capable of cleaving PD-L1 in vitro.
Example 8
Elevated Caspase Activity Inhibits Programmed Cell Death Ligand-1 Expression in Human Leukocytes and is Associated with Active SLE
[0127] As discussed above, APC from patients with active SLE are deficient in PD-L1, but regain the ability to express this protein during disease remissions. Using flow cytometric analysis, the levels of endogenous caspase activity were measured in live APC from children with and without active SLE, and the effect of caspase inhibitors on expression of PD-L1 was tested.
[0128] Active SLE was associated with excessive leukocyte apoptosis, which was inversely correlated with PD-L1 protein levels on APC. Treatment with caspase inhibitors not only reduced leukocyte apoptosis, but also significantly increased expression of PD-L1 on both Mo and mDC. Although PD-L1 levels were elevated by caspase inhibitors, protein expression of CD80/86 was not increased, suggesting an overall decrease in the positive costimulatory capacity of these cells. Caspase inhibitors also increased PD-L1 levels on control and remission APC, suggesting a normal role for these proteases in regulation of this negative costimulatory molecule, and indicating that PD-L1 or its upstream signaling pathways are direct targets of caspases. This indicates that excessive leukocyte caspase activity in active SLE is linked to decreased PD-L1 protein expression on professional APC.
Example 9
[0129] Peripheral venous blood from volunteers was collected into heparin- or citrate-containing tubes (Vacutainer, Becton Dickinson) after informed consent was obtained. Clinical and laboratory data were collected for each sample at the time of blood draw (Table V).
[0000] TABLE V SLE Age at Disease Low C3 Lympho- I.V. Daily oral Subject draw duration &/or C4 penia at SLE I.V. cyclophospha- Daily oral Daily oral pred Weekly oral # Gender (years) (years) at draw draw status b steroids c mide MMF (mg) HCQ (mg) MTX (mg) 1 F 15.5 >5 d na − stable − − − + − − 2 F 12.5 <1 − − stable 2 mo − − + 20 − prior 3 F 15.9 <1 + − stable − − − − ≦10 − 4 F 18.7 1-3 + − stable 3 mo 3 mo − + − − prior prior 5 F 7.7 <1 na − stable − − − + 60 − 8.1 1-3 − − stable 1 mo − 1000 + 15 − prior 6 F 16.1 3-5 na na stable − − − + ≦10 − 17.3 >5 − − stable − − − − − − 7 F 13.1 1-3 − + flare − − − + ≦10 − 15.4 3-5 − + stable >12 mo − >6 mo + ≦10 − prior prior 8 F 15.7 3-5 + − flare − − − + − 15 17.5 >5 − − stable − − − + − 20 9 F 16.0 1-3 + + flare − − − + ≦10 25 18.9 3-5 − + stable − − − + ≦10 2.5 21.2 >5 + − stable − − − + ≦10 − 10 F 10.7 <1 + − stable − − − + − − 11.6 1-3 + − flare − − − + − − 11 F 11.2 <1 + + flare 1 mo 1 mo − + 30 − prior prior 12 F 12.1 <1 + + flare − − − + ≦10 − 13 M 15.0 1-3 − − flare − − − + ≦10 15 14 F 15.6 >5 + + flare − − − + ≦10 − 15 F 17.2 1-3 + + flare − − − + 20 − 16 F 6.4 1-3 + − flare − − − − − − 17 F 9.9 <1 + − flare − − − − − − 18 F 15.4 <1 na − flare − − − − − − 19 F 16.6 <1 na − flare − − − − − −
PBMC were isolated by density centrifugation over a Ficoll-Paque gradient (Amersham), frozen in heat-inactivated AB human serum (Valley Biomedical) with 7% DMSO (Sigma), and stored in liquid nitrogen until use. In preliminary studies, PBMC samples were split into frozen and fresh aliquots and tested to confirm a lack of effect of freeze-thaw on our experimental outcomes.
[0130] PBMC were thawed, washed, and diluted to 1−2×10 6 cells/ml in culture medium consisting of RPMI 1640 with L-glutamine (CellGro), 10% heat-inactivated NB human serum (Valley Biomedical), 1% penicillin/streptomycin (CellGro), and 0.1% beta-mercaptoethanol. Cells were plated in round-bottom 96-well plates (Coming Costar) and incubated at 37° C. in a humidified cell chamber with 5% CO2. Some wells were treated with pan-/poly-caspase inhibitors at the time of plating: 50 uM Q-Val-Asp-(non-o-methylated)-OPh (OPH) or Z-Val-Ala-Asp-(beta-o-methyl)-fluororomethylketone (Z-VAD) (both from R&D Systems), or DMSO as the carrier control (0.5% final concentration).
[0131] At the timepoints indicated, cells were surface-stained using fluorochrome- or biotin-conjugated monoclonal antibodies: anti-CD1c, (Miltenyi), anti-CD3, anti-PD-L1 (eBioscience), anti-CD11b, anti-CD11c, anti-CD14, anti-CD-86, anti-PD-L2 (Pharmingen/BD Biosciences), anti-CD45RO, anti-CD80, anti-CD83, and/or anti-HLA-DR (BioLegend), with isotype-matched, fluorochrome/biotin-labeled irrelevant monoclonal antibodies as controls. All samples were blocked using 0.5% human serum and anti-FeR antibody (Miltenyi) during staining. Cells were fixed using 2% paraformaldehyde in PBS after preliminary experiments indicated no effect of cell fixation on expression levels of PD-L1 and other surface markers. To assess apoptosis, some cultures were stained in parallel with Annexin V and propidium iodide (PI) (both from Becton Dickinson) as per the manufacturer's instructions. Flow cytometry was performed using a FACSCalibur or LSR II cytometer (Becton Dickinson), and data were analyzed using FlowJo software (Macintosh Version 6.3).
[0132] Populations were compared using a 2-tailed t-test, and significance assigned where p<0.05. A total of 26 PBMC samples were collected from 19 SLE patients ranging in age from 6-21 years old (mean=14.3+/−3.7); 13 of these samples were obtained from patients with active (recurrent or newly diagnosed) SLE and designated “flare” samples; 13 were obtained from patients with inactive SLE and designated “remission” samples; (Table I). Control PBMC were obtained from 17 healthy volunteers ranging in age from 6-23 years old (mean=16.5+/−5.3); age was not significantly different between the SLE and control groups. Female subjects comprised 18/19 of the SLE patients and 14/17 of the controls.
[0133] After one day of culture in the absence of exogenously added stimuli, PD-L1 was expressed on a proportion of CD3 − cells from healthy subjects, but there was near-complete absence of PD-L1 on PBMC from patients with active SLE ( FIG. 1A ). CD3 − PBMC from patients in lupus remission had regained the ability to express PD-L1.
[0134] To further characterize these CD3 − PD-L1+ cells, levels of several APC surface markers in control PBMC were and it was found that the PD-L1+ cells were of myeloid lineage by staining for CD14 ( FIG. 1B ). These CD14 lo and CD14 hi populations expressed CD11c, CD11b, CD45RO, and HLA-DR, and corresponded to CD 1c +/− CD80/CD86 hi mDC and CD1c − CD80/CD86 lo Mo populations, respectively, demonstrating that PD-L1 was primarily expressed on professional APC ( FIG. 1C ). Similar to prior findings there was not found a significant amount of CD83 on these cells, supporting the idea that the mOC in these cultures were phenotypically immature. APC profiles in PBMC from patients in SLE flare or remission were similar to those of controls.
[0135] To assess levels of PD-L1 on immature mOC and Mo, PBMC were cultured as above and APC identified by double-staining for CD11c and CD14 ( FIG. 2A ). In comparison to APC from healthy controls, it was found that both immature mOC and Mo from children with active SLE failed to upregulate PD-L1, while APC from children in lupus remission expressed normal or increased amounts of this negative costimulator ( FIG. 2A ). These findings were reproducible using immature mDC and Mo from multiple individuals ( FIG. 2B ). Compared to control APC, mean PD-L1 expression was more than three-fold lower in immature mOC and Mo from children in SLE flare, but nearly two-fold higher in Mo from children in SLE remission, indicating that this negative costimulator may play a role in inhibiting the autoreactive immune response. In support of this concept, serial samples drawn from four patients at different times revealed inverse correlation of PD-L1 expression with SLE disease activity ( FIG. 2C ), with lower levels during lupus flares and higher levels during remissions. Not only were PD-L1 levels significantly lower in SLE flare, but these PBMC also had a lower percentage of APC expressing PD-L1. Two- to three-fold fewer mDC and nearly half as many Mo were PD-L1 + in SLE flare samples as compared to APC from healthy controls and patients in SLE remission ( FIG. 2D ).
[0136] To rule out the possibility that APe from patients with active SLE were merely delayed in upregulation of PD-L1, expression of this protein was measured over a five-day time period ( FIG. 3 ). Normal APC expressed little PD-L1 at initiation of culture, but levels rapidly increased over time, with peak PD-L1 expression in both mDC and Mo by day three ( FIGS. 3A and 3C ). These findings are in agreement with previous work which showed that purified normal human Mo expressed very little PD-1 or PD-L2 upon initial isolation, but spontaneously upregulated PD-L1 after 24 h of culture. As was observed in short-term cultures, it was found that APC from patients in SLE remission expressed PD-L1 at or above normal levels; the kinetics of PD-L1 induction in these cells were similar to those of control cells ( FIGS. 3A and 3C ). In contrast to control APC, immature mDC and Mo from children with active SLE expressed abnormally low levels of PD-L1 throughout the timecourse, refuting the idea that the low PD-L1 observed in day one cultures was merely due to delayed expression.
[0137] Although mean PD-L1 expression was consistently lower in active SLE throughout the timecourse, this was not merely due to a lower proportion of APC expressing PD-L1. The total number of mDC and Mo was quantified at each timepoint, as were the number of cells expressing PD-L1, and it was found that the total numbers of mDC and Mo were not significantly different between samples over time ( FIGS. 3B and D). In active SLE, slightly fewer mDC expressed PD-L1 over the entire culture period ( FIG. 3B ), but the proportion of Mo expressing PD-L1 was similar to that of controls after day one ( FIG. 3D ).
[0138] The finding that immature mDC and Mo failed to upregulate PD-L1 in active SLE has significant implications for pathologic conversion of APC to an immunogenic state. Immature mDC ingest apoptotic bodies and cross-present Ags to cytotoxic T cells and lack of P-1 signaling in vivo results in DC-mediated CD8 + T cell priming rather than tolerization. Therefore, in the absence of PD-L1, autoantigen presentation by lupus mDC may result in T cell activation, rather than tolerogenesis.
[0139] In addition to implications for augmented T effector activity, PD-L1 deficiency may also lead to abnormal T regulatory cell (Treg) function and/or development. Prior work revealed that PD-L1 was necessary for the suppressive activity of classic CD4 + CD25 + Treg in an animal model of GVHD, and that costimulation of naive CD4 + T cells with an anti-CD3 antibody plus PD-L1-Ig fusion protein resulted in formation of Trl regulatory cells.
[0140] It was observed that PBMC from children in SLE flare had the highest level of apoptosis ( FIG. 4A ), and in all cultures, apoptosis was reduced by the addition of OPH, a potent pan-caspase inhibitor ( FIG. 4B ). It was found that OPH also significantly increased PD-L1 expression in Mo of all three groups compared to untreated ( FIG. 4C ), and doubled the mean percentage of Mo expressing PD-L1 in SLE flare (from 45% to 97%). With respect to immature mDC, OPH increased PD-L1 expression in all three groups two- to three-fold (p<0.02), and more than doubled the mean percentage of mDC expressing PD-L1 in all three groups (P<0.013). This concentration of OPH was not sufficient to completely normalize the excessive apoptosis ( FIG. 4B ) nor the deficient Mo PD-L1 expression in SLE flare ( FIG. 4C ), revealing an inverse correlation between apoptosis and PD-L1 ( FIG. 4D ). This reciprocal relationship between caspase activity and Mo PD-L1 expression also held true for all PBMC treated with another caspase inhibitor (Z-VAD).
[0141] APC was examined for expression of CD80 and CD86 in the presence and absence of OPH to determine the potential consequences of decreased PD-L1 in active SLE. In PBMC from healthy controls, CD80/86+ APC were clearly PD-L1 + in the absence of exogenous stimuli, and upregulated PD-L1 further after treatment with OPH ( FIG. 7 ). In contrast, untreated APC from children with active lupus were markedly PD-L1-deficient without any apparent deficiency in expression of CD80/86; suggesting a high level of positive costimulatory capacity in these cells. In the presence of OPH, PD-L1 levels in SLE flare APC approached those of untreated control cells ( FIG. 7 ), indicating that the abnormal balance of costimulatory signaling in lupus APC could be ameliorated by inhibition of caspases.
[0142] Insults which promote apoptosis, such as drugs, infection, or UV irradiation, may inhibit APC from expressing PD-L1 due to activation of caspases. PD-L1-deficient APC could then play a role in triggering lupus-like symptoms by presenting apoptosis-related antigens in an inflammatory context, providing a final common pathway for breakdown of peripheral tolerance in SLE. Pristane, which causes a lupus-like syndrome when injected into normal mice, and chlorpromazine, which causes a lupus-like syndrome in humans, activate caspases and trigger apoptosis in leukocytes. Infliximab, which can cause a lupus-like syndrome in susceptible individuals, was recently shown to promote caspase activation and apoptosis in human macrophages. The above experiments showed that the failure of APC to upregulate PD-L1 contributes to abnormal T lymphocyte regulation and loss of peripheral tolerance in SLE.
Example 10
[0143] Paediatric donors with and without SLE were recruited under a research protocol. Peripheral venous blood was collected into heparin- or citrate-containing tubes (Vacutainer, Becton Dickinson, N.J., USA) after written informed consent was obtained from the child and/or parent/guardian. Blood samples were centrifuged and plasma aliquots. Peripheral blood mononuclear cells (PBMC) were isolated by density centrifugation over a Ficoll-Paque gradient (Amersham, Uppsala, Sweden), frozen in heat-inactivated AB human serum (Valley Biomedical, Winchester, Mass., USA) with 7% DMSO (Sigma, St. Louis, Mo., USA), and stored in liquid nitrogen until use. In preliminary experiments, PBMC samples from four unique donors were split into frozen and fresh aliquots, and evaluated by flow cytometry to confirm, a lack of effect of freeze-thaw on expression levels of PD-L1 (P≧0.7).
[0144] Clinical and laboratory data were collected for each individual, and all but one of the lupus patients fulfilled the current ACR classification criteria for SLE. As this was a retrospective study, the European Consensus Lupus Activity Measurement (ECLAM) was calculated for all patient samples where information was available (n=24); ECLAM scores ranged from 0 to 6.5, with a mean±S.D. of 2.5±2.0. As no patient had documentation of seizures, psychosis, cerebrovascular accident, cranial nerve disorder, visual disturbance, myositis, pleurisy, pericarditis, intestinal vasculitis or peritonitis at the time of blood draw, we used a modified scoring system to group patients with respect to disease activity, consisting of these remaining categories: mucocutaneous disease (rash, alopecia, mucosal ulcers and finger nodules), arthritis, haematuria, thrombocytopenia and hypocomplementaemia. In addition, we used lymphopenia, rather than leucopenia, as a sensitive measure of active paediatric SLE. Several samples were chosen at random and also assayed for PBMC apoptosis and/or plasma levels of IFN-α, as these markers are strongly linked to SLE disease activity. PBMC apoptosis was considered to be abnormally high if outside the bounds of the 99.95% CI of control cells (PBMC from seven healthy children tested, data not shown) and plasma IFN-α levels were considered to be abnormal if ≧5 times the upper limit of normal (six healthy children tested).
[0145] As the clinical assessments were gleaned from chart notes written by a panel of different physicians, the objective laboratory data were weighted more heavily in the final determination, with each abnormal laboratory value assigned 2 points, and each abnormal clinical finding assigned 1 point. A total disease activity score of ≧4 points was felt to represent active disease, and called ‘flare’, while a score of <4 was felt to represent inactive disease, and called ‘remission’. This modified scoring system has the limitation that it has not been formally validated; however, there are no validated disease activity scoring systems for paediatric SLE. Moreover, when this modified scale was used to categorize patients into flare and remission groups, the mean ECLAM scores and anti-dsDNA antibody levels were found to be significantly different between the two groups (Table I), suggesting the potential utility of this approach.
[0146] PBMC were thawed, washed and diluted to 1−2×10 6 cells/ml in culture medium consisting of RPMI 1640 supplemented with L-glutamine (CellGro, Herndon, Va., USA), 10% heat-inactivated A/B human serum, 1% penicillin/streptomycin (CellGro) and 0.1% β-mercaptoethanol. Cells were plated in round-bottom 96-well plates (Corning Costar, Corning, N.Y., USA) and incubated at 37° C. in a humidified cell chamber with 5% CO 2 . At the time points indicated, PBMC were surface-stained using various fluorochrome- or biotin-conjugated mAbs, including: anti-CD1c, (Miltenyi, Auburn, Calif., USA), anti-CD3, anti-PD-L1 (eBioscience, San Diego, Calif., USA), anti-CD11b, anti-CD11c, anti-CD14, anti-CD-86, anti-PD-L2 (Pharmingen/BD Biosciences), anti-CD45RO, anti-CD80, anti-CD83 and/or anti-HLA-DR (BioLegend, San Diego. Calif. USA), with isotypematched, fluorochrome-/biotin-labelled irrelevant mAbs as controls.
[0147] All samples were blocked using 0.5% human serum and anti-FcR antibody (Miltenyi) during staining. After staining, PBMC were fixed using 2% paraformaldehyde in PBS after preliminary experiments indicated no effect of cell fixation on expression levels of PD-L1 or other surface markers (data not shown). Some cultures were stained in parallel with Annexin V and propidium iodide (PI) as per the manufacturer's instructions (both from Becton Dickinson) and apoptosis assessed by enumerating the percent of Annexin V-positive PBMC per culture. Flow cytometry was performed using an LSR II cytometer (Becton Dickinson), and the data were analysed using Flow Jo software (Tree Star, Inc., Ashland, Oreg., USA).
[0148] Populations were compared using a two-tailed t-test and significance assigned where P<0.05. Due to the fact that some patients had more than one blood draw and were therefore overrepresented in the data set, statistical analyses were repeated using multivariate logistic generalized estimating equations (GEEs), to account for multiple observations in some individuals. Results of GEE analyses confirmed P<0.05 between populations as identified by t-test.
[0149] A total of 26 PBMC samples were collected from 19 unique SLE patients ranging in age from 6 to 21 yrs (mean±S.D.=14.3±3.7). Clinical and laboratory data for these blood draws are summarized in Table I. Overall, 12 samples were obtained from patients with active (recurrent or newly diagnosed) SLE and categorized as ‘flare’ samples, while 14 were categorized as ‘remission’ samples, as outlined above. Patient age was not significantly different between the SLE flare (13.8±3.1) and remission (14.7±4.2) groups, and there were no statistically significant differences between the groups with respect to medication usage. Control PBMC were collected from 15 healthy volunteers ranging in age from 6 to 23 yrs (15.7±5.2); patient age and gender composition were not significantly different between the control and SLE groups. Females comprised 18/19 of the SLE patients and 12/15 of the controls.
[0150] To test the hypothesis that PD-L1 expression is abnormal on lupus APC, primary human PBMC were cultured for 1 day in the absence of exogenously added stimuli and PD-L1 levels measured using four-color multiparametric flow cytometry. Consistent with prior findings in normal human leucocytes, we observed virtually no PD-L1 protein on CD3 + cells, but PD-L1 was expressed on a proportion of CDT cells from a healthy subject ( FIG. 1A ). In contrast, there was near-complete absence of PD-L1 on PBMC from a patient with active SLE. Surprisingly, CD3 − cells from the same patient during lupus remission had regained the ability to express normal levels of PD-L1. This pattern was reproducible using PBMC from multiple individuals (see below).
[0151] To characterize the CD3 − cells expressing PD-L1, we assessed levels of several surface markers on normal PBMC and found that the PD-L1 + cells naturally segregated into CD14-low/negative (CD14 lo ) and CD14-high (CD14 hi ) populations ( FIG. 1B ), demonstrating that PD-L1 was primarily expressed by APC of myeloid lineage, consistent with published data. Examination of the CD14 lo and CD14 hi APC subsets for CD11c, CD11b, CD1c, CD45RO and HLA-DR revealed expression patterns consistent with immature mDC and Mo, respectively ( FIG. 1C ). Similar to a prior report, we did not observe a significant amount of CD83 on these cells, supporting the idea that the mDC in these cultures were phenotypically immature.
[0152] To confirm abnormal PD-L1 levels on lupus APC, PBMC were cultured as above and immature mDC and Mo identified by co-staining for CD14 and CD11c ( FIG. 13A ). As noted, we found that both immature mDC and Mo from children with active SLE failed to up-regulate PD-L1, while APC from children in lupus remission expressed normal or increased levels of this negative costimulator ( FIG. 13B ). As the CD14 lo CD11c + populations in PBMC may have been comprised of a heterogenous mix of differentiating Mo and early mDC, we used the cell surface marker CD1c (BDCA-1) to specifically identify Type I mDC. Gating for CD14 lo CD11c + CD1c + cells revealed PD-L1 expression consistent with that of the CD14 lo CD11c + population as a whole, confirming the utility of this method for measuring PD-L1 levels on immature mDC ( FIG. 13C ).
[0153] These findings were reproducible and statistically significant for immature mDC and Mo from multiple individuals ( FIG. 13D-F ). Compared with control APC, mean PD-L1 expression was more than 3-fold lower on immature mDC and Mo from children in SLE flare, but nearly 2-fold higher on Mo during SLE remission ( FIG. 13D ). To correct for potential inter-experiment variation, the PD-L1 MFI for each set of APC was normalized to background levels, using the PD-L1 MFI of the CD14 − CD11c − cells as the denominator for each sample. However, mDC and Mo from patients in SLE flare remained significantly PD-L1-deficient as compared with both normal and remission APC ( FIG. 13E ) Not only were PD-L1 protein levels lower on SLE flare APC, but there were also lower percentages of cells expressing PD-L1 ( FIG. 13F ). Compared with controls, PD-L1 was expressed on nearly 70% fewer SLE flare mDC and nearly 50% fewer Mo. In contrast, the percentages of PD-L1 + APC in lupus remission samples were not significantly different than in controls, consistent with the idea that this negative costimulator may play a role in inhibiting the autoreactive immune response. In support of this concept, serial samples drawn from four patients at different times revealed an inverse correlation between Mo PD-L1 expression and disease activity, with lower levels during SLE flares and higher levels during remissions ( FIG. 13G ).
[0154] To rule out the possibility that APC from patients with active SLE were merely delayed in up-regulation of PD-L1, we measured expression of this protein over a 5 day culture period. Normal APC expressed little PD-L1 at initiation of culture, but levels rapidly increased over time, with peak PD-L1 expression in both immature mDC and Mo by days 1-2, and return to baseline by day 5. In contrast, immature mDC and Mo from children with active SLE expressed abnormally low levels of PD-L1 throughout the time course, refuting the idea that the low PD-L1 observed in day 1 cultures was merely due to delayed surface expression of this protein. As in short-term cultures, APC from children in SLE remission exhibited normal or elevated levels of PD-L1, suggesting a potential functional association between PD-L1 expression and disease activity.
[0155] In contrast to PD-L1, staining of control PBMC for the related negative co-stimulator. PD-L2, revealed a nearly negligible level of protein expression that did not change over 4 days of culture. These findings are in agreement with previous work that showed that purified Mo from healthy adult volunteers expressed virtually no PD-L1 or PD-L2 upon initial isolation, and spontaneously up-regulated only PD-L1 after 24 h of culture.
[0156] To determine whether the defect in lupus flare APC was specific to PD-L1, we measured the level of positive co-stimulatory molecules (a combination of CD80 plus CD86) on PBMC from children with and without SLE. We found that although immature mDC and Mo were clearly PD-L1-deficient during SLE flare, they retained the ability to express CD80/CD86 ( FIG. 14 ), congruent with prior studies that revealed normal or elevated levels of these proteins on mDC and Mo from patients with SLE, Taken together, these observations suggest that the inability of lupus APC to express PD-L1 cannot be attributed to a global decrease in costimulatory molecule expression during SLE flare, and that loss of the negative PD-L1 signal is not associated with or compensated for by a decrease in positive co-stimulatory signals.
[0157] Consistent with a prior report, we also observed that although Mo populations were fairly homogenous with respect to expression of CD80/CD86, immature mDC segregated into CD80/CD86 lo and CD80/CD86 hi -expressing groups, suggesting differing abilities for T-cell stimulation ( FIG. 14 ). Moreover, in control and SLE remission PBMC, the majority of PD-L1 protein was expressed by CD80/CD86 hi mDC, suggesting that T-cell stimulation by these most potent APC is normally held in check by this negative regulator. Surprisingly, the CD80/CD86 hi subset of mDC was markedly lacking in SLE flare, although the reasons for this are currently unclear.
[0158] The finding of decreased PD-L1 protein during active SLE has significant implications for conversion of APC to a pathological state. Although immature mDC and Mo from children with active SLE failed to up-regulate PD-L1, both cell types retained the ability to express several other markers, including CD80/CD86, at the APC surface. As CD80/CD86-mediated T-effector signaling is normally countered by PD-L1, lupus APC could potentially have an abnormally high capacity for positive T-cell co-stimulation during SLE flare. A hyperstimulatory role for lupus APC is supported by data showing that mDC and Mo from patients with SLE have an increased ability to activate allogenic T-cells.
[0159] Not only do DCs depend upon PD-L1 signaling to diminish T-cell stimulation, but negative co-stimulation by PD-L1 is more effective in immature DCs than in mature DCs, suggesting a mechanism for the immunogenic presentation of autoantigens in SLE. Immature mDC ingest apoptotic bodies and cross-present Ags to cytotoxic T-cells, and lack of PD-1 signaling in vivo results in DC-mediated CD8 + T-cell priming rather than tolerization. Therefore, our data may provide a partial explanation for the self-reactivity observed in lupus patients, whereby PD-L1-deficient immature mDC present apoptosis-related antigens in a pro-inflammatory context.
[0160] While examining CD80/CD86 expression, it was also noted that the CD80/CD86 hi subgroup of mDC was diminished during SLE flare. This is intriguing, as SLE PBMC proliferate poorly in autologous mixed leucocyte reactions (aMLRs), and it has recently been suggested that CD80/CD86 hi mDC are integral for T-cell proliferation during aMLRs. The reason behind the loss of these cells in active SLE is unclear, however, and may be related to increased apoptosis or to tissue sequestration—it has been reported that patients with active Class III and IV lupus nephritis have significantly fewer circulating mDC along with a concomitant increase of immature mDC in renal tissues. It would be interesting to determine whether these renal mDC retain the ability to express PD-L1.
[0161] In addition to potentially stimulating autoreactive T effector cells, PD-L1-deficient APC may promote abnormal function and/or development of regulatory T lymphocytes (Treg). It has been demonstrated that PD-L1 signaling is necessary for the suppressive activity of classic CD4 + CD25 + Treg in an animal model of GVHD, and that anti-CD3-stimulated naïve CD4p T cells could be induced to become Trl-type regulatory cells if co-stimulated with PD-L1-Ig. Although decreased Treg number and function have been reported in human SLE it remains to be determined whether PD-L1 plays any role in Treg-related deficiencies.
[0162] The decreased PD-L1 levels observed on APC from patients with active SLE were not likely a result of medication effects, as the use of immunosuppressive agents was comparable between flare and remission groups (Table I). Three of the children with active SLE and low PD-L1 had been newly diagnosed and had never received any immunosuppression. Additionally, all four of the subjects who provided serial samples ( FIG. 2G ) were on minimally varying medication regimens at the time of their blood draws. Similarly, a prior study of SLE patients revealed no correlation between the use of immunosuppressive agents in vivo and changes in cell surface markers on peripheral blood DC, as well as no significant effect of chloroquine, steroids, 6-mercaptopurine or mycophenolate mofetil on markers of Mo differentiation and maturation in vitro.
[0163] In addition to cytokine dysregulation, SLE leucocytes undergo apoptosis at an increased rate, and we did note an inverse correlation between PD-L1 expression and PBMC apoptosis (Table I). Following this lead, we have preliminary data demonstrating that in vitro treatment of PBMC with polycaspase inhibitors not only reduced leucocyte apoptosis, but increased the expression of PD-L1 on mDC and Mo in all cultures (data not shown). These findings suggest a role for caspase activity in the normal regulation of PD-L1 and provide a potential explanation for the loss of this negative co-stimulator on APC from patients with active SLE. In support of this idea, it has been reported that caspase-3 is directly responsible for the decreased CD3 − -chain expression on the surface of SLE T cells.
[0164] Our findings complement what is already known regarding PD-L1 expression in human disease; levels of PD-L1 are increased on circulating APC from patients with chronic HIV, hepatitis B or hepatitis C infection, and decreased on DC from patients with multiple sclerosis. As preliminary studies in our laboratory have also indicated abnormally low levels of PD-L1 on APC from patients with some other types of active autoimmune disease, we propose that diminished expression of PD-L1 on circulating APC may be a hallmark of active multi-organ autoimmunity, while elevated levels of PD-L1 on circulating APC may be indicative of chronic infection. If verified in larger samples, this distinction may be medically useful, as it is often unclear whether clinical deterioration in SLE patients represents disease flare or infection.
[0165] In summary, our findings link active SLE with the inability of peripheral blood APC to express PD-L1, suggesting that PD-L1 may be functionally important in the maintenance of immune tolerance in SLE. Lack of this protein on the surface of immature mDC also suggests a mechanism for the propensity of the immune system to target apoptosis-associated molecules in SLE, as immature mDC typically ingest and present these self-antigens. Given the inverse correlation between PD-L1 and SLE disease activity, future investigations may reveal a role for PD-L1 fusion proteins or other molecules capable of ligating PD-1 in the treatment of SLE or other autoimmune diseases. Larger studies may determine whether intermittent measurements of PD-L1 on circulating APC could provide an additional tool for monitoring the clinical course of SLE. The above experiments showed that both immature mDC and Mo from children with SLE failed to up-regulate PD-L1 normally, and that this deficiency was associated with increased disease activity.
[0166] As used herein, the term “patient” refers to the recipient of a therapeutic treatment and includes all organisms within the kingdom animalia. In preferred embodiments, the animal is within the family of mammals, such as humans, bovine, ovine, porcine, feline, buffalo, canine, goat, equine, donkey, deer and primates. The most preferred animal is human.
[0167] As used herein, the terms “treat” “treating” and “treatment” include “prevent” “preventing” and “prevention” respectively. As used herein, the term “autoimmune disease” includes “immune-related disease,” “autoimmune disorder,” “immunologic disorder” and “immune-related disorder.” As used herein, the term “isolated” refers to materials, such as cells or antibodies, which are removed from at least some of the components that normally accompany or interact with the materials in a naturally occurring environment such that they have been altered, “by the hand of man” from their natural state to a level of isolation or purity that does not naturally occur.
[0168] In some other embodiments, the treatments described herein may be administered alone or in combination with another therapeutic compound. Any therapeutic compound used in treatment of the target autoimmune disease can be used.
[0169] Many different modes and methods of administration of the therapeutic molecules are contemplated. In some embodiments, delivery routes include, for example, intravenous, intraperitoneal, inhalation, intramuscular, subcutaneous, nasal and oral administration or any other delivery route available in the art. Depending on the particular administration route, the dosage form may be, for example, solid, semisolid, liquid, vapor or aerosol preparation. The dosage form may include, for example, those additives, lubricants, stabilizers, buffers, coatings, and excipients available in the art of pharmaceutical formulations. In some embodiments, gene therapy is utilized to deliver therapeutic molecules to the patient.
[0170] Many pharmaceutical formulations are contemplated. In some embodiments, the pharmaceutical formulations can be prepared by conventional methods using the following pharmaceutically acceptable vehicles or the like: excipients such as solvents (e.g., water, physiological saline), bulking agents and filling agents (e.g., lactose, starch, crystalline cellulose, mannitol, maltose, calcium hydrogenphosphate, soft silicic acid anhydride and calcium carbonate); auxiliaries such as solubilizing agents (e.g., ethanol and polysolvates), binding agents (e.g., starch, polyvinyl pyrrolidine, hydroxypropyl cellulose, ethylcellulose, carboxymethyl cellulose and gum arabic), disintegrating agents (e.g., starch and carboxymethyl cellulose calcium), lubricating agents (e.g., magnesium stearate, talc and hydrogenated oil), stabilizing agents (e.g., lactose, mannitol, maltose, polysolvates, macrogol, and polyoxyethylene hydrogenated castor oil), isotonic agents, wetting agents, lubricating agents, dispersing agents, buffering agents and solubilizing agents; and additives such as antioxidants, preservatives, flavoring and aromatizing agents, analgesic agents, stabilizing agents, coloring agents and sweetening agents.
[0171] If necessary, glycerol, dimethyacetamide, 70% sodium lactate, surfactants and alkaline substances (e.g., ethylenediamine, ethanol amine, sodium carbonate, arginine, meglumine and trisaminomethane) can also be added to various pharmaceutical formulations.
[0172] In the context of some embodiments, the dosage form can be that for oral administration. Oral dosage compositions for small intestinal delivery include, for example, solid capsules as well as liquid compositions which contain aqueous buffering agents that prevent the expanded T reg cell population or other ingredients from being significantly inactivated by gastric fluids in the stomach, thereby allowing the expanded T reg cell population to reach the small intestines. Examples of such aqueous buffering agents which can be employed in the present invention include, for example, bicarbonate buffer at a pH of from about 5.5 to about 8.7. Tablets can also be made gastroresistent by the addition of, e.g., cellulose acetate phthalate or cellulose acetate terephthalate.
EQUIVALENTS
[0173] The foregoing written specification is considered to be sufficient to enable one skilled in the art to practice the invention. The foregoing description details certain preferred embodiments of the invention and describes the best mode contemplated by the inventors. It will be appreciated, however, that no matter how detailed the foregoing may appear in text, the invention may be practiced in many ways and the invention should be construed in accordance with the appended claims and any equivalents thereof. | Disclosed herein are methods of treatment of autoimmune diseases such as systemic lupus erythematosus (SLE) as well as clinical assays for detection of autoimmune disease activity in patients utilizing a PD1 ligand. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. § 119(e) from U.S. Provisional Application Ser. No. 60/016,534, filed May 3, 1996, by applicants Richard C. Wu, William C. Lanter and Peter Bletzinger, entitled Process For Large Area Deposition Of Diamond-Like Carbon Films. The invention description contained in that provisional application is incorporated by reference into this description.
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
BACKGROUND OF THE INVENTION
The present invention relates generally to ion beam deposition processes, and more specifically to an improved ion beam process for depositing diamond-like carbon coatings onto a variety of substrates.
Diamond-like carbon (DLC) coatings have become an area of intense research and experimentation. Diamond-like carbon generally consists of hydrocarbon structures that exhibit properties similar to those of diamonds. Diamond-like carbon exhibits a low coefficient of friction, high wear resistance, extreme hardness, extreme corrosion resistance and exceptional scratch resistance. DLC used as a hard coating has diverse applications in such areas as tribology, optics and electronics.
A particular advantage of DLC coatings is that they can be applied at relatively low temperatures, typically lower than 300° C. Diamond coatings, while usually displaying physical properties superior to those of DLC coatings, are created at much higher temperatures, typically higher than the melting temperature of the substrate onto which a coating is desired to be placed.
Many different methods for depositing DLC films or coatings currently exist. Several elements are common among these methods. Typically, a DLC deposition apparatus consists, in its most basic form, of an ion gun or ion source, an evacuation or vacuum chamber, and an apparatus for holding a substrate to be coated.
Prior art methods for producing DLC films utilize as an ion source derivatives of a so-called Kaufman source. A Kaufman ion source incorporates high current metallic filaments (so-called hot-filament sources) mounted inside a vacuum vessel to ionize hydrocarbon gas molecules, such as methane (CH 4 ), to form a carbon rich plasma which is accelerated by the beam of ions from the Kaufman source to strike a substrate to be coated with the DLC film or coating.
Unfortunately, conventional prior art methods for depositing DLC coatings using Kaufman sources have many drawbacks. The primary disadvantage is that metal vapor produced by hot filaments inside the vacuum chamber contaminates the carbon ions extracted from the plasma. Moreover, the hot filaments have very short lifetimes, typically only a few hours, depending on the gaseous mixture and pressure.
Additionally, these prior art ion deposition methods only enable the user to deposit DLC onto a small planar surface area of a substrate. This severely limits the usefulness, particularly the commercial usefulness, of diamond-like carbon coatings.
A very important limitation of prior art methods is the types of substrates onto which DLC coatings can be successfully deposited. Adhesion between DLC and many substrates, particularly metals, is typically extremely poor due to the inherent compressive stress of DLC. The DLC film will usually expand or contract when removed from the vacuum chamber and that expansion or contraction results in compressive stresses inside the film which can make it peel away from the substrate. Existing methods of deposition attempt to remedy this problem by introducing an intermediate layer, such as silicon (Si), between the substrate and the DLC. This is done by first depositing the intermediate layer onto the substrate and then depositing the DLC on top of the intermediate layer.
There is a need in the prior art not only for improved apparatus for depositing DLC coatings, but also for the effects of control parameters such as ion energy, power, gas composition and substrate temperature on DLC characteristics. Those characteristics include such properties as adhesion to substrate, friction and wear behavior, infrared (IR) transmission and electrical properties. To date, despite much experimentation, and despite improved apparatus such as is described as part of the present invention, ion beam deposition of DLC coatings having characteristic properties suitable for a desired application is, at best, a hit or miss process. By "at best" is meant that most often no successful DLC coating for a particular application can be achieved. By "hit or miss" is meant that, even when successful DLC coatings are achieved, they are not repeatable and control parameters for achieving a practical degree of repeatability are not well defined.
An example of an application for DLC coatings is as a coating for infrared window materials. Zinc selenide (ZnSe) and zinc sulfide (ZnS) are currently used as domes or windows in infrared sensor systems. These are excellent optical materials for applications throughout the infrared and visible regions of the spectrum. Unfortunately, these materials are mechanically soft and undergo significant degradation when subject to chemical attack, rain erosion and sand impact. Thus, the development of economical techniques to significantly improve the hardness of these materials without degrading the integrity of the specular transmittance is a great current interest. DLC coatings, if they can be successfully applied to ZnS and ZnSe surfaces, will be of great value.
Another example of an application for DLC coatings is as a coating for surfaces intended to be used in the ultrahigh vacuum of space. An example of such a surface is chemical-vapor deposited (CVD) fine-grain diamond coatings. Both the coefficients of friction (0.4 to 2.0) and the wear rate (10 -4 mm 3 /Nm) of CVD diamond films are considerably higher than in air or in dry nitrogen. The presence of an amorphous, nondiamond carbon layer on CVD diamond films decreases both friction and wear in ultrahigh vacuum, resulting in a low steady-state coefficient of friction (<0.1) and a low wear rate (≦10 -6 mm 3 /Nm) One method for producing such a layer on CVD diamond films is ion implantation. Ion implantation produces acceptable levels of friction and wear of CVD diamond films, but the depth of implantation is very shallow which may limit the tribological applications of ion implantation to light loads or short-term operations. The thickness range of DLC films can be 0.1 to 5 μm, an order of magnitude greater than ion-implanted layers. Therefore, an amorphous DLC film coated on a CVD diamond film can enhance the tribological properties of such films, particularly for increasing the endurance of CVD diamond films.
Thus it is seen that there is a need for an improved method for successfully depositing diamond-like carbon coatings directly onto a variety of substrate materials, and for the control parameters necessary for successful application of DLC coatings onto specific substrates.
It is, therefore, a principal object of the present invention to provide an improved method for depositing diamond-like carbon coatings onto a variety of substrate materials, and to define the control parameters necessary for successful application of DLC coatings onto specific substrates.
It is a feature of the present invention that its ion beam source will not contaminate ions extracted from the ion plasma.
It is a feature of the present invention that the characteristics of the source plasma can be monitored and controlled so that a user can monitor and control on a real-time basis the resulting characteristics of the diamond-like carbon coating.
It is another feature of the present invention that its ion beam source has an extended lifetime and more efficiently transfers ions to a substrate.
It is an advantage of the present invention that it can deposit diamond-like carbon coatings over large and nonplanar substrate surface areas.
SUMMARY OF THE INVENTION
The present invention provides a highly efficient method for depositing diamond-like carbon coatings directly onto substrates having large nonplanar surface areas and specific control parameters for successfully applying DLC coatings on zinc sulfide and zinc selenide infrared window surfaces. The disclosed method uses a high power, radio frequency excited-inductively coupled ion gun, along with a four-axis scanner for moving substrates and an on-line quadrupole mass spectrometer for monitoring ion composition. The radio frequency (RF) excited-inductively coupled ion gun provides a source of contamination-free ions and an ion source with an extended lifetime. The scanner allows nonplanar surfaces to be coated with DLC films by providing movement in 4 planes, X, Y, θY and θZ. The quadrupole mass spectrometer provides for in-situ monitoring of the characteristics of the ion beam, and consequently the characteristics of the resulting DLC coating.
Accordingly, the present invention is directed to an ion beam method for depositing a diamond-like carbon film onto a substrate, comprising the steps providing a vacuum chamber, providing a radio frequency excited inductively coupled ion source for generating an ion beam of carbon-hydrogen ions inside the vacuum chamber, and accelerating the ion beam towards the substrate. The method may further comprise the step of providing a four-axis scanner for moving the substrate across the ion beam.
The present invention is additionally directed to an ion beam method for depositing a diamond-like carbon film onto a zinc sulfide or a zinc selenide substrate, comprising the steps of providing a vacuum chamber, providing a radio frequency excited inductively coupled ion source for generating an ion beam of carbon-hydrogen ions inside the vacuum chamber, and accelerating the ion beam towards the zinc sulfide substrate, wherein the accelerating energy for the ion beam is about 750 eV. The carbon-hydrogen ions may be generated from a flow of CH 4 gas and H 2 gas, wherein the ratio of the flow rate of the CH 4 gas to the flow rate of the H 2 gas is about 0.68. The radio frequency energy supplied by the radio frequency excited inductively coupled ion source may be about 180 watts.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more clearly understood from a reading of the following detailed description in conjunction with the accompanying drawing, wherein FIG. 1 is a schematic view of a diamond-like carbon ion deposition apparatus made according to the teachings of the present invention.
DETAILED DESCRIPTION
Referring now to FIG. 1 of the drawings, there is shown a schematic view of an ion beam deposition apparatus 10 capable of depositing diamond-like carbon coatings directly onto a substrate. The primary components of ion deposition apparatus 10 are a vacuum, or deposition, chamber 12, a radio frequency (RF) excited-inductively coupled ion gun 14 and a four-axis scanner 16. Also attached to vacuum chamber 12 is a quadrupole mass spectrometer (not shown).
Deposition chamber 10 is made from stainless steel and is 92 cm in diameter and 102 cm in length. It is pumped by a CTI cyropump 18 capable of pumping 5000 liters per second combined with a Varian Starcell ion pump 20 capable of pumping 230 liters per second. The background pressure is normally 1.33×10 -7 Pa. During deposition, the pressure is about 1.33×10 -2 Pa.
Ion gun 14 is a highly efficient RF (13.56 MHz) inductively coupled ion gun with a diameter of 20 cm made by Nordiko, Inc. and can generate very high beam currents. Highly efficient hollow cathodes 22 are used to discharge Ar to produce electrons for neutralization. The quadrupole mass spectrometer is used on-line to monitor the important ionic species during the deposition process for quality control. A gas inlet system can introduce four premixed gases into the ion source. The flow rate of each gas is controlled by an MKS mass flow controller. The gases used are methane (99.99%), argon (99.99%) and hydrogen (99.99%).
Ion gun 14 creates a broad ion beam 24 as a result of its 20 cm diameter antenna/coil. Ion gun 14 utilizes RF source 26 to create and excite the ions which form the ion beam 24. Radio frequency source 26 is inductively coupled to vacuum chamber 12 through a dielectric window 28. Dielectric window 28 forms one end of a plasma generation region 30. An acceleration grid and a focusing grid form the other end of plasma generation region 30.
Gas is introduced into plasma generation region 30 where a carbon rich plasma is created. Radio frequency source 26 ionizes this plasma and the acceleration grid and focusing grid transform the plasma into ion beam 24. Resulting ion beam 24 deposits a DLC coating onto the substrate. Ion gun 14 is equipped with neutralizers 22 which neutralize ion beam 24 by adding Ar + ions to the beam.
The energy of ion beam 24 can be varied from 50 eV to 3000 eV.
Four axis substrate scanner 16 is used for coating DLC onto larger areas, typically above 1000 cm 2 . Scanner 16 comprises X-drive motor 34, Z-rotation motor 36, Y-rotation motor 38 and Y-drive motor 40, and sample mounting plates for coupling a substrate to a cooling/heating plate 32. Cooling/heating plate 32 allows the substrate to achieve temperatures between -200° C. and 1000° C. Cooling plate 32 is formed with a chamber spiraling outwardly from its center such that a cooling liquid can flow through the chamber and cool the mounting plate and ultimately the substrate. Scanner 16 provides for a range of motion along 4 axes, X, Y, θY, and θZ, achieved through the use of motors 34, 36, 38 and 40.
The mass spectrometer is coupled to vacuum chamber 12. The mass spectrometer is a quadrupole gas analyzer comprising an analyzer and a Faraday cup. The Faraday cup is constructed from stainless steel and has a 1 cm 2 opening. The Faraday cup is positioned between ion gun 14 and a substrate approximately perpendicular to ion beam 24. The mass spectrometer collects and analyzes positive ion and neutral and free radical molecules in order to determine the composition of ion beam 24.
In use with a substrate, apparatus 10 is used to deposit DLC coatings directly onto one or more dynamic surfaces of the substrate. The substrate is first cleaned through traditional chemical processes. This cleaning process typically involves the use of solvents or other surface cleansers.
Next, the substrate is placed within vacuum chamber 12 and onto the sample mounting plates on scanner 16 through the use of a transfer rod. The substrate is positioned approximately 43.2 cm (17 in.) from ion gun 14.
After the substrate is placed within vacuum chamber 12, pumps 18 and 20 are activated to create a vacuum within vacuum chamber 12. This process includes initial rough pumping and high vacuum pumping. Vacuum chamber 12 is evacuated until its internal pressure is between 6×10 -6 and 2.4×10 -8 torr. Pumps 18 and 20 are continually active during the deposition process so that an internal pressure of 1×10 -3 to 8×10 -5 torr can be maintained.
One or more surfaces of the substrate are first conditioned through ion sputtering. Ion sputtering is accomplished by utilizing ion gun 14 to produce Ar + ions, from argon gas, which are accelerated towards and bombard one or more surfaces of the substrate. The impact of the ions results in a sputtered cleaning of those surfaces. RF ion source 14 can be operated at a relatively low pressure (10 -4 -10 -5 torr) with a sufficiently high beam current. Thus, it is an ideal source for generating atomic ions of Ar + , H + , O + and N + for sputtering and reactive deposition applications. The ion beam current can yield up to 5.4 mA/cm 2 , while the ion energy can be varied from 50 to 3000 eV. A typical N + /N 2 + ion intensity ratio was about 0.4 in the RF power range of 250 W to 500 W. A typical O + /O 2 + ion intensity ratio was 0.28 at RF powers less than 200 W. This ratio increased to 0.35 at RF powers of 300 W and greater.
After the substrate is conditioned, ion gun 14 is activated to begin deposition. Argon gas is introduced into plasma generation region 30 at a rate of 3 to 6 standard cubic centimeters per minute (SCCM). CH 4 gas is introduced into plasma generation region 30 at a rate of 10 to 30 SCCM. H 2 gas is introduced into plasma generation region 30 at a rate of 0 to 34 SCCM. Argon gas is introduced to neutralizers 22 at a rate of 5 SCCM.
The RF power source is set at a forward voltage of 149-300 v. The reflection voltage is set at 0 v to 15 v. The focusing grid is charged to 100-500 v at a current of 5-50 mA. The acceleration grid is charged to 100-1,500 v at a current of 100 mA-700 mA. The deposition process is continued for about 5 minutes and up to 366 minutes.
While deposition is occurring, the mass spectrometer is utilized to monitor the composition of ion beam 24. Based upon the composition of ion beam 24, the control parameters of ion gun 14 can be altered to produce specific desired results.
A substrate cannot dissipate heat because of the vacuumed environment. Thus, the temperature of the substrate is monitored and the substrate may be cooled by using the cooling apparatus of scanner 16. The substrate can be cooled by introducing water or liquid nitrogen into cooling plate 32 which effectuates a heat transfer with the substrate. Ideally, the substrate is kept at approximately room temperature.
Scanner 16 is utilized to move and reposition a substrate such that various portions of one or more surfaces of the substrate are positioned within the path of ion beam 24. The four axes of motion enable all portions of one or more surfaces of the substrate to be oriented at approximately 90° to ion beam 24 in order to completely coat the substrate with a DLC coating. The substrate is continually scanned until a DLC coating which meets predetermined characteristics is deposited onto the substrate.
Ion beam deposition apparatus 10 was used to deposit various DLC films onto a variety of substrates, including ZnS, Cleartran-ZnS, Ge-coated ZnS, Ge-coated Cleartran, Si, aluminum alloys, Ti alloys, polycrystalline diamond, polycarbonates, 304 and 316 stainless steels, 440C and M50 steels, Si 3 N 4 , SiC, glass and quartz. The parameters used for depositing the DLC films were: RF power (100-300 W), ion energy (100-1,500 eV), ion current (100-400 mA), gas mixtures CH 4 /Ar: (0.7-6), CH 4 /H 2 /O 2 : (1:1.5-2:0.15) and CH 4 /Ar/H 2 : (1:0.17:1-2), and substrate temperature (50-230° C.).
As previously described, a substrate cleaning procedure was found to be important in the adhesion of DLC films on various substrate materials. As described, an initial cleaning procedure included regular organic solvent cleaning of substrate surfaces. In addition, for metal and ceramic materials, a beam of Ar + was used to sputter clean the substrate surface prior to deposition. The sputtering rate of Ar + on Si was found to linearly increase with ion energy. Sputtering rates of 195 Å/hr and 15000 Å/hr were measured at 100 eV and 700 eV respectively. A 1/20 mixture of Ar/H 2 was also used to clean the surface of polycarbonates and IR windows. The mass spectra of Ar/H 2 discharges showed that H n + (n=1,2 and 3) were the dominant ions.
In order to maintain a stable RF discharge inside the 20 cm ion source, Ar and H 2 gases were mixed with CH 4 . The deposition rate of DLC was found to be strongly dependent upon the gas mixture (Ar/CH 4 , H 2 /CH 4 ), ion energy and substrate materials. Mass spectra showed that CH 3 + is the dominant hydrocarbon ion. The Ar + and ArH + ions were also important depending upon the Ar/CH 4 ratio. In the gas mixture of H 2 /CH 4 , the H 2 + and H 3 + ions were more dominant than CH 3 + as the ratio of H 2 /CH 4 increased. By introducing Ar in the ion source, the total ion current increases, resulting in an increase in DLC deposition. However, at higher ion energies, the Ar + can sputter the DLC film during the deposition, resulting in a decrease of DLC film growth.
The deposition rate was also found to increase with an increase in ion energy due to better focusing of the ion beam, if the sputtering process was negligible. The rate of DLC on glass substrates was much higher than that on Si. The deposition rate, however, was found to be constant at substrate temperatures in the range of 45-230° C. for a wide range of gas mixtures.
Table I gives the chemical composition of DLC films as a function of substrate materials Si, Ni and Glass at a constant gas mixture (Ar/CH 4 /H 2 ) and ion energy of 1500 eV. Within the analysis uncertainty of the Rutherford Backscattering (±5 atomic percent) and the hydrogen forward scattering (±5 atomic percent) techniques, the carbon and hydrogen contents of these DLC films were found to be the same on semiconductor (Si), insulator (glass) and metal (Ni), although the substrate temperature and the ion-surface interaction were different during the depositions. However, even though the DLC compositions were the same, the microstructure of these films were different, as revealed in the electrical properties as discussed below. The density of the DLC films was calculated to be varied from 1.6 to 2.0 g/cc depending on the hydrogen content.
TABLE 1______________________________________Deposition Conditions and ChemicalComposition of RF Ion Beam Diamond-like CarbonIon Source ParametersExpt. No./ CH.sub.4 Ar RF Ion Energy DLC CompositionsSubstrate (ratio) (w) (eV) C H Ar C/H______________________________________91/Silicon 5.7 1 149 1500 63.3 36 0.70 1.76(100)91/Glass 5.7 1 149 1500 63.6 35 1.3 1.8291/Nickel 5.7 1 149 1500 65 35 1.86______________________________________
The dielectric constant (ε) of DLC films are calculated from the measured capacitance value by the simple formula:
ε=C L/A (1)
where C is the capacitance, A is the area and L is the thickness of the DLC film. It is interesting to note that under the same plasma parameters, the dielectric constant of the DLC films deposited on Si and glass was found to be 7.2 and 3.9 respectively, even though both DLC chemical compositions (carbon and hydrogen contents) were the same, as shown in Table I. Therefore, it is suggested that the bond polarizability in a random network of the DLC films deposited on Si and glass were different.
The dielectric constant of DLC films deposited on glass was found to increase from 2.8 at an ion energy of 500 eV to 3.9 at 1500 eV. The Raman spectra of these samples indicated that the G-position increased as the ion energy increased. From this, it is suggested that sp 2 bonding is more prevalent in the DLC films deposited at high ion energies.
Table II gives the friction and wear behavior of DLC films on Si 3 N 4 and polycrystalline diamond films examined in an ultrahigh vacuum environment. The results of these experiments demonstrate that in ultrahigh vacuum both the steady-state coefficient of friction and the wear factor of the DLC films were very low, i.e., 0.04 and <10 -6 mm 3 /Nm respectively. Thus, the DLC films produced by the present RF ion beam technique can provide solid-lubrication and wear resistance in space-like environments.
Furthermore, using the present ion beam deposition technique, it is possible to deposit uniform DLC films, a few micrometers thick, on large flat and curved surfaces.
TABLE II__________________________________________________________________________Friction and Wear Factor of Diamond-LikeCarbon Under UHV Environment Tribology Properties Ion Source Parameters Wear CH.sub.4 Ar H.sub.2 RF Ion Energy DLC Composition Coefficient FactorExpt. No./Substrate (ratio) (W) (eV) C H Ar C/H of Friction (mm.sup.3 /Nm)__________________________________________________________________________156/Si.sub.3 N.sub.4 1 0 2 150 600 59.5 40 0.06 1.49 0.14 <2 (Rev.)157/Si.sub.3 N.sub.4 1 0 2 150 500 59.5 40 0.06 1.49 0.1 500 (Rev.)158/Si.sub.3 N.sub.4 1 0.18 0 176 750 59 40 0.27 1.48 0.07 4100 (Rev.)126/Diamond 1 0.18 0 99 1500 59 36 1.8 1.64 0.05 4.68E-06129/Diamond 1 0.18 0 99 57 42 0.8 1.36 0.04 1.80E-06__________________________________________________________________________
As previously discussed, ZnS and ZnSe are currently used as domes or windows in infrared sensor systems. Unfortunately, also as previously discussed, these materials are mechanically soft and undergo significant degradation when subject to chemical attack, rain erosion and sand impact. Thus, the development of economical techniques to significantly improve the hardness of these materials without degrading the integrity of their specular transmittance has been of current interest. The development of an adhering diamond-like carbon hard coating on these materials has been investigated using the teachings of the present invention.
Due to compressive stresses of DLC films, direct deposition of DLC films on ZnS surfaces was limited to <0.3 μm. A thin layer (0.2 μm) of DLC film containing 4% O 2 in the ion source gas mixture (CH 4 /H 2 =1:2) with an RF power of 179 W and 750 eV ion energy was used. This was followed by depositing a 2 μm thick DLC film with a gas mixture of CH 4 /H 2 =1:2 in the ion source. This thick combination of DLC films on ZnS successfully passed the environmental tests of high humidity and salt fog. The refractive index of the oxygen containing DLC film was found to be 1.95-2.05 in the IR region of the spectra, and that of the DLC film without the oxygen was measured to be 2.0. The mass spectra of the CH 4 /H 2 gas mixture showed CH 3 + , H 3 + , H 2 + and H + as the dominating ions. An additional H 3 O + (m/e=19) ion appeared when O 2 was introduced into the CH 4 /H 2 mixture. The ion intensity of H 3 O + increased as the O 2 concentration increased. The effect of oxygen on the chemical composition of the DLC film is not known at the present time. The refractive index of the DLC film increased slightly with a decrease in ion energy, i.e., the refractive index was 2.1 and 2.2 at ion energies of 750 eV and 500 eV respectively. However, the hardness of these DLC films was found to be the same at 1500 kg/mm 2 .
For the most successful adhesion to ZnS of a coating that had the desired index of refraction of about 2.0, a single layer of DLC was applied with the following control parameters. The RF energy from the ion gun was 180 watts, the ion acceleration energy was 750 eV, and the ratio of CH 4 to H 2 was 0.68, with no O 2 present. The same control parameters will apply to coating ZnSe. The tradeoff for ion energies is that higher energies provide better adhesion, but produce a more graphitic coating. Lower ion energies produce a better material, but do not adhere as well.
Composition of DLC films was determined by Rutherford backscattering (RBS) and hydrogen forward scattering (HFS) techniques. The bonding structure of DLC was studied by Raman spectroscopy and FTIR techniques. Cross sectional electron microscopy was also performed and the deposited DLC films were found to be uniform and pin-hole free. Optical characterizations were carried out in the visible and IR regions. Rotating sliding friction experiments were conducted with CVD diamond pins (radius, 1.6 mm) with a load of 0.49 N, at a constant rotating speed of 120 rpm at room temperature under ultrahigh vacuum (10 -7 Pa). Refractive indexes were determined in the IR region of the spectra. Dielectric constants were determined by capacitance measurements. The environmental tests were performed under humidity (95-200% relative humidity, 50° C. for 10 days), and salt fog (5% NaCl at 50° C. for 24 hours) environments.
The disclosed system for depositing DLC films successfully demonstrates the advantages of using a filament-less RF excited inductively coupled ion gun combined with a four axis scanner and an in-situ mass spectrometer. Although the disclosed invention is specialized, its teachings will find application in other areas where existing methods are limited by prior art apparatus components.
It is understood that various modifications to the invention as described may be made, as might occur to one with skill in the field of the invention, within the scope of the claims, Therefore, all embodiments contemplated have not been shown in complete detail. Other embodiments may be developed without departing from the spirit of the invention or from the scope of the claims. | A new method for ion beam deposition of diamond-like carbon coatings onto a variety of substrates is described. A high power, radio frequency excited-inductively coupled ion gun directs a beam of carbon and hydrogen ions at a substrate inside an ultra vacuum deposition chamber. A four axis scanner is used for coating large and nonplaner substrates. A quadrupole mass spectrometer is mounted inside the deposition chamber for real time monitoring of ion composition. The disclosed method is particularly effective for coating zinc sulfide and zinc selenide infrared windows. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to improvements in a bundling apparatus for automatically bundling bar-like articles such as steel bars, wire rods, etc. by means of a bundling wire.
2. Description of the Prior Art
Briefly describing the construction and operation of the generally used bundling apparatus, it comprises a wire feeding mechanism for feeding a bundling wire from a supply source, a wire guide path for guiding and winding the fed wire around a material to be bundled, and a twist shaft for finally twisting together the opposite ends of the wire, and further comprises important components such as a sensing device for sensing the completion of feeding of a necessary length of wire, a cutting device for the bundling wire and a bending device for bending the opposite ends of the wire. Moreover, the steps performed by the above-described devices must be a series of associated steps progressing with time and therefore, for example, the bending device or the cutting device must be disposed so as to be driven by independent drive sources while, at the same time, a limit switch for instructing the initiation or stoppage of the drive and a relay or a cam device for interlocking the limit switch must be provided. This necessitates excess space and complicates the entire apparatus. There is, therefore, a great possibility of trouble in the apparatus. The system heretofore employed as the sensing device for sensing the completion of the feeding of the bundling wire is directed to the sensing of pressure imparted by the leading end of the wire to a stop or to sensing lateral pressure provided by the leading end of the wire contacting the stop which curvedly deforms the wire in the feeding path, and depends on a mechanical impulse caused by the wire. Such means does not always exhibit the expected mechanical impulse when the fed wire accidentally has a slight inadvertent bend for some reason or other, and cannot be called a reliable sensing device.
The present invention overcomes the disadvantages peculiar to the prior art apparatus and realizes a bundling apparatus in which independent drive sources and accessory instruments for controlling the starting and stoppage of these drive sources are simplified for the series of steps forming the bundling operation, to thereby effect a plurality of processes efficiently.
Further, the present invention provides a sensing device of higher reliability for sensing the completion of the feeding of the wire and which does not depend on a mechanical impulse.
SUMMARY OF THE INVENTION
In the bundling apparatus of the present invention, a power shaft is provided on a common axis on the extension of the axis of a twist shaft for the bundling wire and an outer structure is provided between and coaxially with the twist shaft and the power shaft.
A pair of opposed differential bevel gears with the common axis interposed therebetween are provided on the outer structure in a direction perpendicular to the common axis. A bevel gear at the end of the power shaft meshes with the differential bevel gear from one side thereof and a bevel gear at the end of the twist shaft meshes with the differential bevel gear from the other side thereof. The outer structure itself is supported for rotation about said common axis by a bearing provided outside the body thereof, and the power shaft and the twist shaft are supported for rotation about said common axis at positions proximate to the meshing bevel gears by said outer structure. Thus, the differential gearing is interposed between the outer structure and the power shaft and the twist shaft.
Means for angularly limiting and stopping the rotation of the outer structure is attached with respect to the outer structure, and means for bending and cutting the bundling wire is provided at the end of the outer structure which is adjacent to the twist shaft. Means for stopping the rotation of the twist shaft is attached with respect to the twist shaft, and two holes for passing therethrough the bundling wire are provided at the twist end of the twist shaft which is opposite from the bevel gear.
Further, bundling wire guide means including a sensing device for sensing completion of the winding operation of the bundling wire is disposed above the twist end of the twist shaft.
With such a construction, if the power shaft is rotated in a predetermined direction and the outer structure is held stationary by its stop means, the twist shaft rotates in the direction opposite to the direction of rotation of the power shaft due to the principle of the differential device, and if the outer structure is released and the twist shaft is held stationary by its stop means, the outer structure rotates in the same direction as the power shaft.
Thus, if the power shaft is moved upon sensing of completion of the winding operation of the bundling wire and the twist shaft is made stationary at this time, only the outer structure is rotated to cut and bend the distal ends of the bundling wire wound around a material to be bundled. When the outer structure is stopped after a limited angular rotation, the twist shaft is released from its stoppage and starts to rotate in the direction opposite to the direction of rotation of the power shaft and thus, the ends of the wire in the two holes are drawn out of these holes and twisted together. After the twist shaft has made a number of revolutions necessary for twisting together the wire ends, the power shaft is stopped from rotating and the ends of the wire twisted together are pushed down to terminate the bundling of the material to be bundled.
Thereafter, when the power shaft is started in the opposite direction, the outer structure is rotated in the same direction as the power shaft (in the direction opposite to the previous direction of rotation) and is stopped after a limited angular rotation. Thereupon, the twist shaft starts rotating and after a certain angular rotation, the twist shaft is stopped by its stop means, thus completing a cycle of bundling operation.
Moreover, the above-described series of processes can be accomplished by the movement of a single power shaft from a single drive source.
It is an object of the present invention to provide a bundling apparatus in which a series of main processes forming the bundling operation may be accomplished by a single power shaft system.
It is another object of the present invention to provide a bundling apparatus in which a single power shaft system includes a differential gearing device.
It is still another object of the present invention to provide a bundling apparatus in which accessory instruments for controlling the start and stop of the series of main processes are simplified.
It is yet still another object of the present invention to provide a bundling apparatus in which the sensing device for sensing the completion of feeding of the bundling wire is a highly reliable sensor which does not depend on a mechanical impulse.
These and other objects and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partly cross-sectional front view of the bundling apparatus according to the present invention.
FIG. 2 is a side view of the bundling apparatus.
FIG. 3 is an enlarged cross-sectional view showing the components in the vicinity of the twist shaft of the bundling apparatus.
FIG. 4 is a side view corresponding to FIG. 3.
FIGS. 5A, 5B, 5C, and 5D illustrate the bundling operation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIGS. 1 and 2, a continuous wire 1 for bundling is fed via a guide 2 toward the peripheral groove of a feed pulley 3 and guided by pinch rollers 4, 5 and 6 to guides 7 and 7'. Designated by 8 is a feed motor which is operable by a sensing device to be described, to intermittently drive the feed pulley 3 in forward and backward directions. The leading end of the wire 1 having left the guide 7' passes through one of two holes, 10, formed in the end face opposite to the drive side end of a twist shaft 9 and is guided in the form of a loop and passes through another hole 11 so that the leading end of the wire is blocked against further advance by a recess 13 for stopping the leading end of the bundling wire formed in a cutter 12. Such construction is enlarged in FIGS. 3 and 4. In FIGS. 1 to 4, reference numeral 14 denotes a power shaft, and 15 a motor for driving the power shaft 14. Designated by 16 is an outer structure (in the present embodiment, it is cylindrical and referred to as the outer wheel) which is supported for pivotal movement about an axis 50 common to the axis of the power shaft 14 and the twist shaft 9, and a pair of opposed bevel gears 17, 18 are mounted on the inner side of the outer wheel. The bevel gears 17 and 18 respectively mesh with a bevel gear 19 provided at the end of the power shaft 14 and a bevel gear 20 provided at one end of the twist shaft 9, and these together constitute a differential gearing mechanism.
A sector stop 21 is provided on the outer periphery of the outer wheel 16, and a limit plate 36 (see FIG. 3) corresponding to the sector stop is secured to the housing 51 of the bundling apparatus. Thus, the outer wheel 16 is rotatable through a limited angle about the axis 50. A concave groove 39 is provided in the outer periphery of the twist shaft 9, and a stop 22 is provided with respect to the housing 51 of the bundling apparatus. The stop 22 is generally formed into an L-shape and a shaft 43 is provided on the bend of the L-shape so as to permit rotation, and the end of the lower arm 42 of the L-shape is pulled on by a spring 23. Thus, the stop 22 is normally urged against the twist shaft, and when the concave groove 39 of the twist shaft meets the claw 41 of the stop 22, the claw 41 enters the concave groove 39 to hold the twist shaft stationary. Therefore, if the power shaft 14 is rotated in a predetermined direction by the motor 15 and the outer wheel 16 is prevented from rotating by the abuttment of the sector stop 21 with the limit plate 36, the twist shaft 9 rotates in the direction opposite to the direction of rotation of the power shaft due to the principle of the differential gearing. If the outer wheel 16 is released by the sector stop 21 and the twist shaft 9 is stopped by the engagement between the concave groove 39 of the twist shaft 9 and the claw 41 of the stop 22, the outer wheel 16 rotates in the same direction as the power shaft. Thus, it becomes possible to cause, a plurality of functions in associated steps required in the bundling apparatus and continuous with time, to be continuously performed by a single power shaft. Designated by 23 is a spring for the stop 22, and 24 a roller for drawing out the stop 22 from the twist shaft 9. The roller 24 is loosely fitted on a shaft studded in the end face of the outer wheel 16 and when the counter-clockwise rotation of the outer wheel 16 in FIG. 4 is brought to an end by the abuttment of the sector stop 21 with the limit plate 36, the roller 24 comes into engagement with an upward extension 44 of the stop 22 to draw out the claw 41 of the stop from the concave groove 39 of the twist shaft 9 against the force of the spring 23 (FIG. 5D).
As best illustrated in FIG. 4, the cutter 12 is installed on the end face of the outer wheel 16 and is rotatable with rotation of the outer wheel 16 to cause the leading end 1a of the wire 1 held in the bundling wire end stopping recess 13 to be bent along the peripheral surface of the twist shaft 9 by a projected piece 25, while the cutter still continues to rotate. The cutting edge 26, which is also an extension of the cutter 12, cooperates with the guide 7', which functions as a fixed cutting edge, to cut the wire 1 at a portion which is to be the trailing end 1b of the wire 1 and at the same time, the trailing end 1b cut by the cutting edge 26 is bent along the peripheral surface of the twist shaft 9. Designated by 27 is a lever for pushing down the twisted portion of the leading and trailing ends of the wire 1 after twisting together by the rotation of the twist shaft 9. The alternate movements of push-down and return of the lever 27 may be imparted by change-over of the pressure oil fed into cylinders 28 and 29.
Designated by 30 in FIG. 3 is a guide provided with a sensing device for sensing the completion of the winding operation of the wire 1. In the course of the wire passageway formed through the guide 30, there is provided an electrical wire 31 forming an opposing terminal and a weak current may be passed therethrough to sense the variation in the conducted current resulting from the passage of the wire, thereby stopping the feed motor 8 for the feed pulley 3 and stopping the supply of the wire 1. Of course, a relay is interposed therebetween so as to effect the regulation of the timing such that the supply of the wire is stopped immediately after the leading end 1a of the wire 1 has come into the back of the recess 13. Designated by 33 is an opening-closing guide for winding the bundling wire, 34 a fixed guide and 35 a swinging motor for opening and closing the opening-closing guide 33.
The bundling operation effected by the apparatus of the present invention will now be described.
Description will first be made of the initial positions of the various parts of the bundling apparatus. The outer wheel 16 is in a position wherein the left end of the sector stop 21 is stationary and bears against the limit plate 36 (as clearly seen in FIGS. 5A and 4), and accordingly, the cutter 12 and the roller 24 are also in the positions shown in FIGS. 5A and 4. The twist shaft 9 is in an angular position wherein the two holes 10 and 11 at the end thereof face in the vertical direction to receive the leading end of the bundling wire paid away from the guide 7'. At the same time, the claw 41 of the stop 22 is engaged with the concave groove 39 of the twist shaft 9 to bring about the stationary position of the twist shaft. The motor is stopped. For the clear understanding of the apparatus of the present invention, the above described position of each part is referred to as the bundling cycle starting position.
However, for the completion of the bundling operation, the other operations must be described. In starting the bundling operation, the opening-closing guide 33 should be opened to the position as indicated by dots-and-dash line in FIG. 1, by the swinging motor 35. Next, a material to be bundled (not shown) is placed at a suitable position in proximity to the fixed guide 34. Subsequently, the swinging motor 35 is operated to close the opening-closing guide 33 and when the feed motor is started in the forward direction in response thereto, the wire 1, which has so far been held stationary with the leading end thereof cut at the lower end exit of the guide 7', is fed from the guide 7' with the rotation of the feed pulley 3, passes through one hole 10 at the end of the twist shaft 9 and is guided by the fixed guide 34 and the opening-closing guide 33 to wrap the material to be bundled, in a loop form. The wire then passes through a hole in the guide 30 into the other hole 11 at the end of the twist shaft 9. At this time, the wire passes through the weak current path formed by the electrical wire 31 to increase the current conducted therethrough and such variation in the current is sensed to stop the wire feed motor 8 at the appropriate time, with the leading end 1a of the wire 1 passing through the hole 11 into the recess 13 of the cutter 12.
Simultaneously therewith, the motor 15 is started to rotate the power shaft 14 in counter-clockwise direction as viewed in FIGS. 4, 5A, 5B, 5C and 5D. At this time, the outer wheel 16 and the twist shaft 9 are in the bundling cycle starting position as previously described. Therefore, rotation of the twist shaft 9 is stopped by the stop 22 while the outer wheel 16 is free to rotate in a counter-clockwise direction. Thus, the rotative drive of the power shaft 14 is transmitted only to the outer wheel 16. Moreover, in the embodiment shown, the rotational torque of the outer wheel 16 is increased to twice the rotational torque of the power shaft 14 and the outer wheel effects rotation in the same direction as the power shaft at half the rotational speed of the latter. Operation after the initiation of rotation of the outer wheel 16 will hereinafter be described by reference to FIGS. 5A, 5B, 5C and 5D.
In FIG. 5, reference numeral 36 designates a limit plate secured to the housing 51 to limit the movement of the sector stop 21 secured to the outer wheel 16. Liners 37 are attached to the opposite ends of the limit plate to alleviate the shock occurring at each terminus of movement of the sector stop 21. As seen in FIG. 5A, initially, the twist shaft 9 is held stationary by the stop 22 while the outer wheel 16 is free to rotate in a counter-clockwise direction. Thus, the outer wheel 16 is rotated counter-clockwise with the rotation of the power shaft 14 so that the projected piece 25 on the cutter 12 strikes the leading end 1a of the wire. In the manner described above, the leading end 1a of the wire is bent by the projected piece 25 and the outer wheel further continues to rotate to the position as shown in FIG. 5B. This rotational position is detected by a detector means and the detection signal is transmitted to the feed motor 8. Thereupon, the feed motor 8 starts its reverse rotation to pull back the bundling wire 1 in the direction opposite to the feed direction, whereby the wire loop tightens around the material to be bundled.
By this time, the leading end 1a of the wire has already been bent and so, the tightening operation is performed stably. When the tightening force reaches a predetermined value, the operating oil pressure of the feed motor 8 is increased to open a pressure switch and cut off the supply of pressure oil, thereby stopping the reverse rotation of the feed motor 8. In this state, the outer wheel 16 further continues to rotate and the cutting edge 26 of the cutter 12 reaches the portion of the wire 1 which is to be the trailing end of the wire, and cooperates with the guide 7' to cut the wire, and further advances to bend the cut trailing end 1b in the direction of rotation. Thereupon, as shown in FIG. 5C, the roller 24 on the outer wheel 16 is moved with the outer wheel 16 into contact with the upward extension 44 of the stop 22. When the outer wheel is further rotated to the position of FIG. 5D, the roller 24 on the stop 22 against the force of the spring 23 and draws out the claw 41 of the stop 22 from the concave groove 39 of the twist shaft 9 to enable the twist shaft 9 to rotate. On the other hand, the sector stop 21 on the outer wheel 16, with the liners 37, is stopped from further rotation by engagement with the limit plate 36, and accordingly, the rotative drive of the power shaft 14 thereafter is transmitted through the differential gearing to the twist shaft 9 to rotate the twist shaft in the reverse direction (clockwise).
When the twist shaft 9 is rotated, the opposite ends of the wire 1 retained in the holes 10 and 11 are drawn out of these holes and twisted together. A detector for detecting the number of revolutions necessary for the twisting together is provided on the twist shaft at a suitable location, and it detects the completion of the necessary revolutions to stop the motor 15 while, at the same time, pressure oil is supplied to the cylinder 28 to push down the twisted portion by means of the lever 27. Thereafter the oil pressure supplied to the cylinder 28 is changed over to the cylinder 29 to return the lever 27 back to its initial position. The motor 15 is the started in clockwise direction. At this time, the roller 24 of the outer wheel 16 is subjected to a clockwise force by the extension 44 of the stop 22 and thus, the outer wheel can start to rotate in clockwise rotation. When the roller 24 is disengaged from the stop extension 44, the stop 22 is rotated clockwise by the spring 23 to cause the claw of the stop 22 to push against the periphery of the twist shaft 9, and the twist shaft 9 is prevented from rotating by the frictional force produced therebetween (even if the claw 41 is not engaged with the concave groove 39).
Thus, the outer wheel 16 is rotated clockwise from the position of FIG. 5D back to the position of FIG. 5A until the opposite side liner 37 bears against the limit plate 36, whereupon the clockwise rotation of the outer wheel 16 is stopped. At this time the twist shaft 9 starts to rotate in counter-clockwise direction against the aforementioned frictional force and when the concave groove 39 of the twist shaft 9 rotates to the position of the claw 41 of the stop 22, the stop now released from the roller 24 causes the claw 41 to enter the concave groove 39 due to the resilient force by the spring 23, so that the twist shaft 9 stops rotating. By sensing this, the motor 15 stops its clockwise revolution and the entire apparatus is returned to the bundling cycle starting position. In the meantime, the bundled material for which the operation of pushing down the twisted portion has been completed operates the swinging motor 35 in response to completion of said operation to thereby open the opening-closing guide 33 to permit the removal of the bundled material.
A feature of the apparatus according to the present invention is this: the rotative drive of the power shaft may be transmitted to the twist shaft through a differential gearing mechanism and, therefore, the rotational torque produced in the outer wheel 16 by stopping the twist shaft is very strong, as already described, and the apparatus of the present invention entirely eliminates the need to mount a fly-wheel on the drive shaft in order to store the energy needed for shearing the wire. Cutting of the bundling wire requires a particularly strong force among the bundling operations, and the great rotational torque produced in the outer wheel can readily perform the step of cutting the bundling wire.
With such a construction of the bundling apparatus according to the present invention, the number of drive sources and accessory instruments for controlling these drive sources can be reduced as compared with the conventional apparatus. This leads to simplification of the entire apparatus and reduces the space space occupied by the apparatus, as well as reduces the possibility of occurrence of trouble. Also, each process function installed on the outer wheel is imported a strong torque as compared with the drive torque for the twisting step of the twist shaft. This eliminates the need to provide means for storing the drive energy as has heretofore been required and leads to a very simple construction of the drive mechanism, which can perform a plurality of processes by a single power shaft.
Further, the sensing device for sensing the completion of supply of the wire and for halting the supply of the wire is very reliable in operation and enables a highly reliable sensing operation to be effected by a simple construction. | In an automatic bundling apparatus for bar steel, die steel, steel pipes, wire rods, etc., a power shaft and a twist shaft are disposed coaxially and a differential gearing mechanism is interposed between and coaxially with the power shaft and the twist shaft. The functions such as clamping of the bundling wire end, cutting of the wire and twisting of the wire which are the main operations in bundling are performed by the same hydraulic motor through the utilization of the differential gearing mechanism. | 1 |
This application claims the benefit of provisional application Serial No. 60/165,912, filed Nov. 17, 1999.
BACKGROUND OF THE INVENTION
Responsible pet ownership has come to constitute more than just feeding and walking one's dog. Pet excrement deposited in public places is not only aesthetically unappealing, but poses numerous health risks and can adversely effect the environment. Exposure to pet excrement can result in E. coli ( Escherichia coli ) bacteria or roundworm infestation; and E. coli bacteria and roundworms can survive in tainted soil long after the excrement has degraded. Further, improperly disposed of pet excrement can be transferred into our waterways by storm water, potentially leading to water pollution that can reach hazardous levels and threaten aquatic life.
What was once considered to be exclusively an urban concern is no longer isolated to that context, as greater public awareness of the health concerns created by publicly deposited pet excrement, and laws and ordinances created in response thereto, have resulted in increased numbers of pet owners who responsibly “clean up” after their pets. Unfortunately, “cleaning up” after one's pet is inconvenient and requires special considerations. Specifically, the actual process of collecting pet excrement can be discomforting and unsanitary; the excrement itself cannot be discarded in just any trash receptacle, due to the obvious differences between excrement and typical garbage items; and the materials used to collect pet excrement, such as slow or non-degrading plastic bags, often introduce other environmental issues. The present invention resolves the aforementioned issues by minimizing the personal discomfort and unsanitary circumstances associated with collecting pet excrement, while allowing for convenient and environmentally conscious disposal of the excrement in an ordinary toilet.
The present invention relates to: Biodegradable bags that will degrade when immersed in an aqueous environment but will resist degradation when only the exterior surface of the bag comes in contact with liquid; A process for manufacturing biodegradable bags that will degrade when immersed in an aqueous environment but will resist degradation when only the exterior surface of the bag comes in contact with liquid; and A method for using biodegradable bags that will degrade when immersed in an aqueous environment but will resist degradation when only the exterior surface of the bag comes in contact with liquid to pick up pet excrement and dispose of such excrement in an ordinary toilet.
U.S. Pat. No. 5,679,421 describes a biodegradable bag of two ply construction, comprising an inner layer of specific thermoplastic materials and an outer paper layer. The materials are all biodegradable and the thermoplastic materials selected are purportedly resistant to the passage of liquid there through. Of the thermoplastic materials described, those that successfully resist the passage of water there through do not degrade in an aqueous environment and those that are degradable in an aqueous environment do not resist the passage of water there through and are hence inappropriate for using to pick up pet excrement.
U.S. Pat. No. 4,902,283 describes an absorbable cleaning mitt for wiping babies that allows the user to clean a baby with the absorbing cotton exterior, while completely protecting the user's hand from that which is being cleaned off of the baby. However, the described mitt is not biodegradable.
SUMMARY OF THE INVENTION
The primary objective of the present invention is to provide a multiple layered bag of such materials that one surface of the bag degrades when it comes in contact with water, while the other surface is water resistant, such that the bag can be used to collect moist materials, for example pet excrement, without exposing the bag handler to those moist materials, yet when the everted bag is subjected to an aqueous environment, with the liquid degradable surface exposed to the aqueous environment, all the components of the bag degrade. The bag degrades such that the remaining components of the bag and the contents thereof are easily flushed down the toilet.
BRIEF DESCRIPTION OF THE DRAWING
By way of further explanation of the invention, exemplary embodiments of the invention will now be described with reference to the accompanying drawings, in which:
FIG. 1 is a cross-section of a multiple layered bag, which embodies the invention;
FIG. 2 is a pictorial view of a multiple layered bag with a hand inserted therein; and
FIG. 3 is a pictorial view of an everted multiple layered bag containing pet excrement.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The apparatuses shown in the accompanying drawing and described below are examples that embody the invention. It should be noted that the scope of the invention is defined by the accompanying claims, and not necessarily by specific features of exemplary embodiments.
FIG. 1 shows a multiple layered bag 10 , having an interior layer 13 made of water-soluble plastic material, like polyvinyl alcohol, an intermediary layer 12 made of water retardant material, like silicone, and an exterior layer 11 made of biodegradable paper, like kraft paper.
Polyvinyl alcohol resins are available in a number of grades of degree of hydrolysis and molecular weight. The degree of hydrolysis and the molecular weight influence the solubility of polyvinyl alcohol resins, but the degree of hydrolysis is by far the more significant of the two variables. For quick dissolution in cold water, resins having a degree of hydrolysis of up to 88% are typically used. Resins having a degree of hydrolysis of 96% to 99.5% are considered to be hot water-soluble only. Resins having a degree of hydrolysis of 88% to 95% can be considered as intermediate in solubility characteristics or “warm water-soluble”. By using combinations of these resins in a water-soluble plastic material formulation, varying degrees of water solubility at given temperatures can be achieved. Variations in the molecular weights of the resins can also influence the water solubility. As such, the formula of the polyvinyl alcohol resin used for the multiple layered bags is modified or selected so that the molecular weight and/or the degree of hydrolysis of the polyvinyl alcohol resin result in the onset of disintegration following exposure to an aqueous environment being preferably delayed for a period ranging from five minutes to one hour or thirty seconds to two hours. At a minimum, the onset of disintegration should be delayed at least thirty seconds to give user time to dispose of the bag and its contents after picking up a moist substance. At the outside, the delay should be no greater than two hours to assure that disintegration begins within a reasonable time after disposal.
The bag sheet material can be made by spraying the water retardant material 12 on one surface of the water-soluble plastic material 13 , then laminating or pressure adhering the biodegradable paper 11 on the water retardant material 12 covered surface of the water-soluble plastic material 13 . Selected areas of two sheets of the multiple layered bag material are joined together, to form a bag construction 10 having an interior layer 13 made of water-soluble plastic material and an exterior layer 11 made of biodegradable paper. Alternatively, selected areas of one sheet of the multiple layered bag material are joined together, to form a bag construction 10 having an interior layer 13 made of water-soluble plastic material and an exterior layer 11 made of biodegradable paper.
Alternatively, the bag sheet material can be made by spraying the water retardant material 12 on one surface of the biodegradable paper 11 , then laminating, pressure adhering, or spraying the water-soluble plastic material 13 on the water retardant material 12 covered surface of the biodegradable paper 11 . Selected areas of two sheets of the multiple layered bag material are joined together, to form a bag construction 10 having an interior layer 13 made of water-soluble plastic material and an exterior layer 11 made of biodegradable paper. Alternatively, selected areas of one sheet of the multiple layered bag material are joined together, to form a bag construction 10 having an interior layer 13 made of water-soluble plastic material and an exterior layer 11 made of biodegradable paper.
As another alternative, the bag sheet material can be made by creating one layer composing both the water retardant material 12 and the biodegradable paper 11 , by adding the water retardant material 12 , a resinous or starch-like material, during the slurry phase of the biodegradable paper 11 manufacture, then laminating, pressure adhering, or spraying the water-soluble plastic material 13 on the water retardant biodegradable paper 12 and 11 . Selected areas of two sheets of the multiple layered bag material are joined together, to form a bag construction 10 having an interior layer 13 made of water-soluble plastic material and an exterior layer 11 made of biodegradable paper. Alternatively, selected areas of one sheet of the multiple layered bag material are joined together, to form a bag construction 10 having an interior layer 13 made of water-soluble plastic material and an exterior layer 11 made of biodegradable paper.
FIG. 2 shows a multiple layered bag 10 with a hand 20 inserted in the multiple layered bag in such a manner that the hand comes in contact with the water-soluble plastic material interior layer 13 and the exterior biodegradable paper layer 11 covers at least a portion of the bag surface that covers the palmar side of the multiple layered bag 10 . The palmar side of the hand 20 is covered by all layers 11 , 12 , and 13 of the bag 10 so that when the bag 10 covered palmar side of the hand 20 comes in contact with waste materials for disposal 30 , such as pet excrement, the biodegradable paper layer 11 acts to protect the hand 20 from the unpleasant feeling of coming into contact with the waste material 30 and the water retardant layer 12 prevents physical contact between the hand 20 and any components of the waste material 30 , including liquids. Once the palmar side of the bag 10 protected hand 20 is used to collect the waste material, the hand 20 is removed from the bag 10 in such a manner that the bag 10 is everted, leaving the waste material 30 inside the everted bag 10 , with the water-soluble plastic material layer 13 now the exterior layer.
FIG. 3 shows a multiple layer bag 10 that has been everted, contains waste material 30 , and is being carried by a hand 20 . As the waste material 30 has only come in contact with the biodegradable paper layer 11 and not the water-soluble plastic layer 13 , the user can safely hold the everted bag 10 by the water-soluble plastic layer 13 , such that the hand does not come in contact with the waste material 30 or the biodegradable paper layer 11 , which has come in contact with the waste material 30 . The user can safely carry the everted bag 10 to an ordinary toilet, where the everted bag 10 can be discarded into the toilet and the aqueous environment degrades the water-soluble plastic layer 13 and the biodegradable paper layer 11 , leaving the water retardant layer 12 with nothing to be attached to, and hence broken into molecular sized particles which can be flushed down the toilet along with the waste material 30 and the other components of the degraded bag 10 .
The present invention describes biodegradable bags, processes for making such biodegradable bags, and methods, for using such biodegradable bags to collect waste materials, such as pet excrement, and dispose of such bags containing waste material in an ordinary toilet. However, it will be appreciated by those skilled in the arts pertaining thereto, that the present invention can be practiced in various alternate forms and configurations. Further, the previously detailed descriptions of the preferred embodiments of the present invention are presented for purposes of clarity of understanding only, and no unnecessary limitations should be implied therefrom. All appropriate mechanical and functional equivalents to the above, which may be obvious to those skilled in the arts pertaining thereto, are considered to be encompassed within the claims of the present invention. | A multiple layered bag comprising such materials that one surface of the bag degrades when it comes in contact with water, for example polyvinyl alcohol, while the other surface is water resistant, such that the bag can be used to collect moist materials, for example pet excrement, without exposing the bag handler to those moist materials, yet when the everted bag is subjected to an aqueous environment, with the liquid degradable surface exposed to the aqueous environment, all the components of the bag degrade. The bag degrades such that the remaining components of the bag and the contents thereof are easily flushed down the toilet. | 4 |
TECHNICAL FIELD
[0001] The invention relates to active material actuator assemblies.
BACKGROUND OF THE INVENTION
[0002] Active materials include those compositions that can exhibit a change in stiffness properties, shape and/or dimensions in response to an activation signal, which can be an electrical, magnetic, thermal or a like field depending on the different types of active materials. Preferred active materials include but are not limited to the class of shape memory materials, and combinations thereof. Shape memory materials, a class of active materials, also sometimes referred to as smart materials, refer to materials or compositions that have the ability to remember their original shape, which can subsequently be recalled by applying an external stimulus (i.e., an activation signal). As such, deformation of the shape memory material from the original shape can be a temporary condition.
SUMMARY OF THE INVENTION
[0003] Active material actuator assemblies are provided that enable simplified control systems and faster actuation cycle times. In one aspect of the invention, a movable member is provided that has multiple active material components operatively connected to it. The active material components are separately selectively activatable to actuate and thereby move the movable member. Movement of the movable member via activation of a first of the active material components triggers activation of the second active material component to further move the movable member. The activation may be accomplished via activation mechanisms, such as electrical contact strips, that are positioned so that an electrical circuit that activates the second active material component is completed by movement of the movable member in response to the activation of the first active material component. In the case of fluid heating, flow redirecting mechanisms such as spool valves can be arranged so that actuation of the first movable member moves a spool valve to complete another fluid circuit and thereby trigger activation of the second active material component to further move the movable member. Because activation of the second active material component is physically linked to movement of the movable member via the first active material component, control system algorithms to activate the second active material component are not necessary, potentially reducing costs.
[0004] In another aspect of the invention, multiple active material components operatively connected to a movable member are each separately selectively activatable in repeating series for sequential actuation for moving the movable member and are configured such that a previously activated one of said active material components is not reset (e.g., stretched) by actuation of a currently activated active material component. Accordingly, the previously activated component is given time to reduce its resistance to resetting (e.g., to cool) before it is reset and reactivated and thus does not provide resistance during actuation of the currently activated component, increasing efficiency of the actuator assembly.
[0005] In another aspect of the invention, multiple active material components operatively connected to a movable member are each separately selectively activatable in repeating series for moving the movable member and are configured such that a subsequently activated one of said active material components is at least partially reset by actuation of a currently activated one of said active material components. When it is time for the subsequently activated active material component to be activated, it has been wholly reset by one or more of the previously activated active material components to its preactivation state (e.g., a martensite phase in an SMA) in preparation for activation. This “resetting” is physically accomplished via actuation of at least one active material component and therefore additional control system algorithms to reset the active material components are not necessary, potentially reducing costs. Additionally, because the resetting is mechanically accomplished, resetting may be more exact than one accomplished via a control system relying on feedback with its associated inaccuracies.
[0006] The active material actuator assemblies provided herein may function as rotational motors that are more efficient than previous stepping motors that use four shape memory coil springs pulling a biased pin from four different directions to achieve rotation by actuating the SMA springs sequentially. In known stepping motors, only a relatively small force is applied by the springs. Additionally, in such designs after contraction of a spring, it is still relatively hot compared to the ambient temperature and will apply large resistance to the pulling by the next spring compared to the resistance it applies when its temperature is close to ambient (i.e., when in the martensite phase). Finally, there is a waste of the amount of stretch each spring is subjected to since each spring is overstretched by the opposite one and only part of the stretch is used to pull the pin and turn the shaft. The cooperative resistance reduction and resetting mechanism in the rotational motors proposed here can also be used to avoid overstretch such that the full amount of stretch an active material component is subject to is used to do useful work and rotate the shaft.
[0007] The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic, partially cross-sectional illustration of a first embodiment of a telescoping active material actuator assembly;
[0009] FIG. 2 is a graph of load displacement versus time for the active material actuator assembly of FIG. 1 ;
[0010] FIG. 3 is a graph of load holding force versus time for the active material actuator assembly of FIG. 1 ;
[0011] FIG. 4 is a schematic, partially cross-sectional illustration of a second embodiment of a telescoping active material actuator assembly with movable members having bellows;
[0012] FIG. 5 is a schematic, partially cross-sectional illustration in partially fragmentary view of a third embodiment of a telescoping active material actuator assembly having automatic sequential activation;
[0013] FIG. 6 is a schematic illustration of an exemplary embodiment of a locking mechanism for use on any of the actuator assemblies of FIGS. 1 , 4 and 5 ;
[0014] FIG. 7 is a schematic perspective illustration of a fourth embodiment of an active material actuator assembly;
[0015] FIG. 8 is a schematic perspective illustration in cross-sectional view of the actuator assembly of FIG. 7 ;
[0016] FIG. 9 is a schematic fragmentary, cross-sectional view of the actuator assembly of FIGS. 7 and 8 with some of the active material components activated and the movable members locked together;
[0017] FIG. 10 is a schematic perspective illustration of another embodiment of an active material actuator assembly;
[0018] FIG. 11 is a schematic rear view illustration of the active material actuator assembly of FIG. 10 ;
[0019] FIG. 12 is a schematic illustration in fragmentary, partially rotated view of the cam lobe and pulleys of FIGS. 10 and 11 taken along the arrows shown in FIG. 11 ;
[0020] FIG. 13 is a schematic end view illustration of another embodiment of an active material actuator assembly; and
[0021] FIG. 14 is a schematic perspective illustration of the active material actuator assembly of FIG. 13 showing an opposing end.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] A number of exemplary embodiments of active material actuator assemblies within the scope of the invention are described herein. The active material actuator assemblies all utilize active material components that may be, but are not limited to, a class of active materials called shape memory materials. Exemplary shape memory materials include shape memory alloys (SMAs), electroactive polymers (EAPs) such as dielectric elastomers, ionic polymer metal composites (IPMC), piezoelectric polymers and shape memory polymers (SMPs), magnetic shape memory alloys (MSMA), shape memory ceramics (SMCs), baroplastics, piezoelectric ceramics, magnetorheological (MR) elastomers, composites of the foregoing shape memory materials with non-shape memory materials, and combinations comprising at least one of the foregoing shape memory materials. For convenience and by way of example, reference herein will be made to shape memory alloys and shape memory polymers. The shape memory ceramics, baroplastics, and the like can be employed in a similar manner as will be appreciated by those skilled in the art in view of this disclosure. For example, with baroplastic materials, a pressure induced mixing of nanophase domains of high and low glass transition temperature (Tg) components effects the shape change. Baroplastics can be processed at relatively low temperatures repeatedly without degradation. SMCs are similar to SMAs but can tolerate much higher operating temperatures than can other shape-memory materials. An example of an SMC is a piezoelectric material.
[0023] The ability of shape memory materials to return to their original shape upon the application of external stimuli has led to their use in actuators to apply force resulting in desired motion. Smart material actuators offer the potential for a reduction in actuator size, weight, volume, cost, noise and an increase in robustness in comparison with traditional electromechanical and hydraulic means of actuation. However, most active materials are capable of providing only limited displacement, limiting their use in applications requiring a large displacement, whether linear or rotational. The invention described herein solves this problem.
[0024] SMAs
[0025] Shape memory alloys are alloy compositions with at least two different temperature-dependent phases. The most commonly utilized of these phases are the so-called martensite and austenite phases. In the following discussion, the martensite phase generally refers to the more deformable, lower temperature phase whereas the austenite phase generally refers to the more rigid, higher temperature phase. When the shape memory alloy is in the martensite phase and is heated, it begins to change into the austenite phase. The temperature at which this phenomenon starts is often referred to as austenite start temperature (A s ). The temperature at which this phenomenon is complete is often called the austenite finish temperature (A f ). When the shape memory alloy is in the austenite phase and is cooled, it begins to change into the martensite phase, and the temperature at which this phenomenon starts is often referred to as the martensite start temperature (M s ). The temperature at which austenite finishes transforming to martensite is often called the martensite finish temperature (M f ). The range between A s and A f is often referred to as the martensite-to-austenite transformation temperature range while that between M s and M f is often called the austenite-to-martensite transformation temperature range. It should be noted that the above-mentioned transition temperatures are functions of the stress experienced by the SMA sample. Generally, these temperatures increase with increasing stress. In view of the foregoing properties, deformation of the shape memory alloy is preferably at or below the austenite start temperature (at or below A s ). Subsequent heating above the austenite start temperature causes the deformed shape memory material sample to begin to revert back to its original (nonstressed) permanent shape until completion at the austenite finish temperature. Thus, a suitable activation input or signal for use with shape memory alloys is a thermal activation signal having a magnitude that is sufficient to cause transformations between the martensite and austenite phases.
[0026] The temperature at which the shape memory alloy remembers its high temperature form (i.e., its original, nonstressed shape) when heated can be adjusted by slight changes in the composition of the alloy and through thermo-mechanical processing. In nickel-titanium shape memory alloys, for example, it can be changed from above about 100 degrees Celsius to below about −100 degrees Celsius. The shape recovery process can occur over a range of just a few degrees or exhibit a more gradual recovery over a wider temperature range. The start or finish of the transformation can be controlled to within several degrees depending on the desired application and alloy composition. The mechanical properties of the shape memory alloy vary greatly over the temperature range spanning their transformation, typically providing shape memory effect and superelastic effect. For example, in the martensite phase a lower elastic modulus than in the austenite phase is observed. Shape memory alloys in the martensite phase can undergo large deformations by realigning the crystal structure arrangement with the applied stress. As will be described in greater detail below, the material will retain this shape after the stress is removed.
[0027] Suitable shape memory alloy materials include, but are not intended to be limited to, nickel-titanium based alloys, indium-titanium based alloys, nickel-aluminum based alloys, nickel-gallium based alloys, copper based alloys (e.g., copper-zinc alloys, copper-aluminum alloys, copper-gold, and copper-tin alloys), gold-cadmium based alloys, silver-cadmium based alloys, indium-cadmium based alloys, manganese-copper based alloys, iron-platinum based alloys, iron-palladium based alloys, and the like. The alloys can be binary, ternary, or any higher order so long as the alloy composition exhibits a shape memory effect, e.g., change in shape, orientation, yield strength, flexural modulus, damping capacity, superelasticity, and/or similar properties. Selection of a suitable shape memory alloy composition depends, in part, on the temperature range of the intended application.
[0028] The recovery to the austenite phase at a higher temperature is accompanied by very large (compared to that needed to deform the material) stresses which can be as high as the inherent yield strength of the austenite material, sometimes up to three or more times that of the deformed martensite phase. For applications that require a large number of operating cycles, a strain in the range of up to 4% or more of the deformed length of wire used can be obtained. In experiments performed with Flexinol® wires of 0.5 mm diameter, the maximum strain in the order of 4% was obtained. This percentage can increase up to 8% for thinner wires or for applications with a low number of cycles. This limit in the obtainable strain places significant constraints in the application of SMA actuators where space is limited.
[0029] SMPs
[0030] As previously mentioned, other suitable shape memory materials are shape memory polymers (SMPs). “Shape memory polymer” generally refers to a polymeric material, which exhibits a change in a property, such as a shape, a dimension, a shape orientation, or a combination comprising at least one of the foregoing properties in combination with a change in its elastic modulus upon application of an activation signal. Shape memory polymers may be thermoresponsive (i.e., the change in the property is caused by a thermal activation signal), photoresponsive (i.e., the change in the property is caused by a light-based activation signal), moisture-responsive (i.e., the change in the property is caused by a liquid activation signal such as humidity, water vapor, or water), or a combination comprising at least one of the foregoing.
[0031] Generally, SMPs are phase segregated co-polymers comprising at least two different units, which may be described as defining different segments within the SMP, each segment contributing differently to the overall properties of the SMP. As used herein, the term “segment” refers to a block, graft, or sequence of the same or similar monomer or oligomer units, which are copolymerized to form the SMP. Each segment may be crystalline or amorphous and will have a corresponding melting point or glass transition temperature (T g ), respectively. The term “thermal transition temperature” is used herein for convenience to generically refer to either a Tg or a melting point depending on whether the segment is an amorphous segment or a crystalline segment. For SMPs comprising (n) segments, the SMP is said to have a hard segment and (n- 1 ) soft segments, wherein the hard segment has a higher thermal transition temperature than any soft segment. Thus, the SMP has (n) thermal transition temperatures. The thermal transition temperature of the hard segment is termed the “last transition temperature”, and the lowest thermal transition temperature of the so-called “softest” segment is termed the “first transition temperature”. It is important to note that if the SMP has multiple segments characterized by the same thermal transition temperature, which is also the last transition temperature, then the SMP is said to have multiple hard segments.
[0032] When the SMP is heated above the last transition temperature, the SMP material can be imparted a permanent shape. A permanent shape for the SMP can be set or memorized by subsequently cooling the SMP below that temperature. As used herein, the terms “original shape”, “previously defined shape”, “predetermined shape”, and “permanent shape” are synonymous and are intended to be used interchangeably. A temporary shape can be set by heating the material to a temperature higher than a thermal transition temperature of any soft segment yet below the last transition temperature, applying an external stress or load to deform the SMP, and then cooling below the particular thermal transition temperature of the soft segment while maintaining the deforming external stress or load.
[0033] The permanent shape can be recovered by heating the material, with the stress or load removed, above the particular thermal transition temperature of the soft segment yet below the last transition temperature. Thus, it should be clear that by combining multiple soft segments it is possible to demonstrate multiple temporary shapes and with multiple hard segments it may be possible to demonstrate multiple permanent shapes. Similarly using a layered or composite approach, a combination of multiple SMPs will demonstrate transitions between multiple temporary and permanent shapes.
[0034] EAPS
[0035] The active material may also comprise an electroactive polymer such as ionic polymer metal composites, conductive polymers, piezoelectric polymeric material and the like. As used herein, the term “piezoelectric” is used to describe a material that mechanically deforms when a voltage potential is applied, or conversely, generates an electrical charge when mechanically deformed
[0036] Electroactive polymers include those polymeric materials that exhibit piezoelectric, pyroelectric, or electrostrictive properties in response to electrical or mechanical fields. The materials generally employ the use of compliant electrodes that enable polymer films to expand or contract in the in-plane directions in response to applied electric fields or mechanical stresses. An example of an electrostrictive-grafted elastomer is a piezoelectric poly (vinyldene fluoride-trifluoro-ethylene) copolymer. This combination has the ability to produce a varied amount of ferroelectric-electrostrictive molecular composite systems. These may be operated as a piezoelectric sensor or even an electrostrictive actuator.
[0037] Materials suitable for use as an electroactive polymer may include any substantially insulating polymer or rubber (or combination thereof) that deforms in response to an electrostatic force or whose deformation results in a change in electric field. Exemplary materials suitable for use as a pre-strained polymer include silicone elastomers, acrylic elastomers, polyurethanes, thermoplastic elastomers, copolymers comprising PVDF, pressure-sensitive adhesives, fluoroelastomers, polymers comprising silicone and acrylic moieties, and the like. Polymers comprising silicone and acrylic moieties may include copolymers comprising silicone and acrylic moieties, polymer blends comprising a silicone elastomer and an acrylic elastomer, for example.
[0038] Materials used for electrodes of the present disclosure may vary. Suitable materials used in an electrode may include graphite, carbon black, colloidal suspension, thin metals including silver and gold, silver filled and carbon filled gels and polymers, and ionically or electronically conductive polymers. It is understood that certain electrode materials may work well with particular polymers and may not work as well for others. By way of example, carbon fibrils work well with acrylic elastomer polymers while not as well with silicone polymers.
[0039] SMCs/Piezoelectric
[0040] The active material may also comprise a piezoelectric material. Also, in certain embodiments, the piezoelectric material may be configured as an actuator for providing rapid deployment. As used herein, the term “piezoelectric” is used to describe a material that mechanically deforms (changes shape) when a voltage potential is applied, or conversely, generates an electrical charge when mechanically deformed. Preferably, a piezoelectric material is disposed on strips of a flexible metal or ceramic sheet. The strips can be unimorph or bimorph. Preferably, the strips are bimorph, because bimorphs generally exhibit more displacement than unimorphs.
[0041] One type of unimorph is a structure composed of a single piezoelectric element externally bonded to a flexible metal foil or strip, which is stimulated by the piezoelectric element when activated with a changing voltage and results in an axial buckling or deflection as it opposes the movement of the piezoelectric element. The actuator movement for a unimorph can be by contraction or expansion. Unimorphs can exhibit a strain of as high as about 10%, but generally can only sustain low loads relative to the overall dimensions of the unimorph structure. A commercial example of a pre-stressed unimorph is referred to as “THUNDER”, which is an acronym for Thin layer composite UNimorph ferroelectric Driver and sEnsoR. THUNDER is a composite structure constructed with a piezoelectric ceramic layer (for example, lead zirconate titanate), which is electroplated on its two major faces. A metal pre-stress layer is adhered to the electroplated surface on at least one side of the ceramic layer by an adhesive layer (for example, “LaRC-SI®” developed by the National Aeronautics and Space Administration (NASA)). During manufacture of a THUNDER actuator, the ceramic layer, the adhesive layer, and the first pre-stress layer are simultaneously heated to a temperature above the melting point of the adhesive, and then subsequently allowed to cool, thereby re-solidifying and setting the adhesive layer. During the cooling process the ceramic layer becomes strained, due to the higher coefficients of thermal contraction of the metal pre-stress layer and the adhesive layer than of the ceramic layer. Also, due to the greater thermal contraction of the laminate materials than the ceramic layer, the ceramic layer deforms into an arcuate shape having a generally concave face.
[0042] In contrast to the unimorph piezoelectric device, a bimorph device includes an intermediate flexible metal foil sandwiched between two piezoelectric elements. Bimorphs exhibit more displacement than unimorphs because under the applied voltage one ceramic element will contract while the other expands. Bimorphs can exhibit strains up to about 20%, but similar to unimorphs, generally cannot sustain high loads relative to the overall dimensions of the unimorph structure.
[0043] Suitable piezoelectric materials include inorganic compounds, organic compounds, and metals. With regard to organic materials, all of the polymeric materials with noncentrosymmetric structure and large dipole moment group(s) on the main chain or on the side-chain, or on both chains within the molecules, can be used as candidates for the piezoelectric film. Examples of suitable polymers include, for example, but are not limited to, poly(sodium 4-styrenesulfonate) (“PSS”), poly S-119 (Poly(vinylamine) backbone azo chromophore), and their derivatives; polyfluorocarbines, including polyvinylidene fluoride (“PVDF”), its co-polymer vinylidene fluoride (“VDF”), trifluorethylene (TrFE), and their derivatives; polychlorocarbons, including poly(vinylchloride) (“PVC”), polyvinylidene chloride (“PVC2”), and their derivatives; polyacrylonitriles (“PAN”), and their derivatives; polycarboxylic acids, including poly (metharcylic acid (“PMA”), and their derivatives; polyureas, and their derivatives; polyerethanes (“PUE”), and their derivatives; bio-polymer molecules such as poly-L-lactic acids and their derivatives, and membrane proteins, as well as phosphate bio-molecules; polyanilines and their derivatives, and all of the derivatives of tetramines; polyimides, including Kapton molecules and polyetherimide (“PEI”), and their derivatives; all of the membrane polymers; poly (N-vinyl pyrrolidone) (“PVP”) homopolymer, and its derivatives, and random PVP-co-vinyl acetate (“PVAc”) copolymers; and all of the aromatic polymers with dipole moment groups in the main-chain or side-chains, or in both the main-chain and the side-chains, and mixtures thereof.
[0044] Further, piezoelectric materials can include Pt, Pd, Ni, T, Cr, Fe, Ag, Au, Cu, and metal alloys and mixtures thereof. These piezoelectric materials can also include, for example, metal oxide such as SiO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , SrTiO 3 , PbTiO 3 , BaTiO 3 , FeO 3 , Fe 3 O 4 , ZnO, and mixtures thereof; and Group VIA and IIB compounds, such as CdSe, CdS, GaAs, AgCaSe 2 , ZnSe, GaP, InP, ZnS and mixtures thereof.
[0045] MR Elastomers
[0046] Suitable active materials also comprise magnetorheological (MR) compositions, such as MR elastomers, a class of smart materials whose rheological properties can rapidly change upon application of a magnetic filed. MR elastomers are suspensions of micrometer-sized, magnetically polarizable particles in a thermoset elastic polymer or rubber. The stiffness of the elastomer structure is accomplished by changing the shear and compression/tension moduli by varying the strength of the applied magnetic field. The MR elastomers typically develop their structure when exposed to a magnetic field in as little as a few milliseconds. Discontinuing the exposure of the MR elastomers to the magnetic field reverses the process and the elastomer returns to its lower modulus state. Suitable MR elastomer materials include, but are not intended to be limited to, an elastic polymer matrix comprising a suspension of ferromagnetic or paramagnetic particles, wherein the particles are described above. Suitable polymer matrices include, but are not limited to, poly-alpha-olefins, natural rubber, silicone, polybutadiene, polyethylene, polyisoprene, and the like.
[0047] MSMAs
[0048] MSMAs are alloys, often composed of Ni—Mn—Ga, that change shape due to strain induced by a magnetic field. MSMAs have internal variants with different magnetic and crystallographic orientations. In a magnetic field, the proportions of these variants change, resulting in an overall shape change of the material. An MSMA actuator generally requires that the MSMA material be placed between coils of an electromagnet. Electric current running through the coil induces a magnetic field through the MSMA material, causing a change in shape.
[0049] Exemplary Embodiments of Telescoping Active Material Actuator Assemblies
[0050] Referring to FIG. 1 , a first embodiment of an active material actuator assembly 10 is illustrated. The active material actuator assembly 10 has multiple movable members 12 , 14 and 16 and a fixed anchor member 18 . Movable member 14 is referred to in the claims as the first movable member and movable member 16 is referred to as the second movable member. The movable members 12 , 14 and 16 are preferably concentric bodies, which in cross-section may be circular, rectangular, triangular or any other shape, and are arranged in a “telescoping manner” such that movable member 12 is able to move at least partially in and out of movable member 14 , which can move at least partially in and out of movable member 16 , which can move at least partially in and out of anchor member 18 . In alternative embodiments, the movable members 12 , 14 and 16 need not be concentric. The telescoping movable members may be aligned to provide linear movement or may have a curved form to cause nonlinear movement, such as along a circumference of a circle. Multiple active material components are utilized to affect the telescoping movement. An active material component 32 is connected at one end to anchor member 18 and at an opposing end to movable member 16 . Active material component 32 is referred to as the first active material component in the claims. The active material component 32 is shown routed through an opening in a proximal face 34 of movable member 16 and connected to a distal face 36 of the movable member 16 , but could alternatively be connected to the proximal face 34 . Active material component 38 is connected at one end to movable member 16 and at an opposing end to movable member 14 . Active material component 38 is referred to as the second active material component in the claims. The active material component 38 is shown routed through an opening in a proximal face 40 of movable member 14 and connected to a distal face 42 of the movable member 14 , but could alternatively be connected to the proximal face 40 . Active material component 44 is connected at one end to movable member 14 and at an opposing end to movable member 12 . The active material component 44 is shown routed through an opening in a proximal face 46 of movable member 12 and connected to a distal face 48 of the movable member 12 but may alternatively be connected to the proximal face 46 . End anchors 52 secure the respective ends of the active material components 32 , 38 and 44 to the respective movable members and the anchor member. The anchors 52 may be crimped portions of the respective active material components or may be any material capable of restraining an end of the active material component to the respective member, such as a rubber plug, a welded joint or adhesive/epoxy bonded joint.
[0051] In FIG. 1 , three active material components 32 , 38 and 44 are shown. Within the scope of the invention, additional movable members connected with additional active material components may be used. Although the active material components 32 , 38 and 44 are depicted as elongated wires, they may be rods, blocks, springs or any other shape capable of contracting upon activation (or deactivation). Finally, an active material component may consist of multiple discrete active material elements such that multiple active material elements may be connected between a pair of adjacent movable members or between the anchor member 18 and movable member 16 ; i.e., sets of active material components may be used. For example, an additional active material component 19 (shown in phantom) may be connected between the anchor member 18 and the movable member 16 in addition to the single active material component 32 . The active material elements may be in the form of wires or any other geometric shape.
[0052] It should be appreciated that, within the scope of the invention, a single active material component such as an SMA wire may be configured with different regions or segments connecting a movable member to a fixed member having different active material properties such that modulated movement of a load attached to the movable member is achieved between the movable member and the fixed member via the different regions of the single active material component actuating at different times.
[0053] In FIG. 1 , the movable members 12 , 14 and 16 are shown at extreme extended positions, each not able to move any further out of the respective adjacent member due to flange-like stops 20 , 22 , 24 that extend from the respective movable members 12 , 14 and 16 , to interfere with an inner surface of the respective adjacent members at openings 26 , 28 , 30 in movable members 14 , 16 and anchor member 18 through which the movable members 12 , 14 and 16 translate, respectively. The stops 20 , 22 and 24 are integrally arranged such that movement of movable member 16 to the right via contraction of active material component 32 pulls along movable members 12 and 14 , and movement of movable member 14 to the right via contraction of active material component 38 pulls along movable member 12 .
[0054] The active material components 32 , 38 and 44 are shown in the stretched, extended state prior to activation. In the embodiment of FIG. 1 , the active material components 32 , 38 and 44 are SMAs actuated at different respective temperatures which may be achieved by the temperature of the surrounding fluid or by resistive heating serving as an activation signal or trigger. The active material component 32 has the lowest Austenite start temperature, (As) followed by active material component 38 and then active material component 44 (i.e., the active material components are arranged in ascending order of Austenite start temperature (As) from the right). The transformation temperature ranges for each of the active material components 32 , 38 and 44 may be completely distinct or may overlap. The temperature of the active material components 32 , 38 and 44 could be increased by radiative heating, resistive heating (see FIG. 5 ), fluidic (convective) heating (shown as an option in FIG. 1 ) or any combination of the above.
[0055] Return Mechanism
[0056] FIG. 1 contains three respective biasing springs 54 , 56 and 58 acting as return mechanisms urging movable members 16 , 14 and 12 , respectively, to the left (against return to original shape). The biasing springs 54 , 56 and 58 are optional because certain SMA materials with the reversible shape memory effect have the ability to return completely to their original shape without the application of an external restoring force. Also, a restoring force (bias) could be introduced into a load attached to the movable member 12 (or included in movable member 12 ). Furthermore, within the scope of the invention, a design with only one biasing spring 54 could be used. Any other arrangement that puts biasing springs in opposition to the recovery force (i.e., the contraction force) of the active material components could be used, such as arranging the biasing spring external to the movable members 32 , 38 and 44 or using one biasing spring with the load for all of the active material components. Additionally, the stops 20 , 22 and 24 act as overstretch prevention mechanisms as they prevent stretching of the active material components, (due to the return force of the springs 54 , 56 and 58 , respectively) beyond the length determined by interference of the stops 20 , 22 and 24 with respective movable members 14 , 16 and anchor member 18 .
[0057] For purposes of illustration, in the embodiment of FIG. 1 , it is assumed that activation is passively triggered by radiant heating and that the active material components 32 , 38 and 44 are exposed to the same surrounding temperature. As the temperature of the active material components 32 , 38 and 44 increases, the transformation of active material component 32 occurs first. Consequently, movable member 16 is pulled to the right and with it, due to the stops 20 and 22 , movable members 12 and 14 , and therefore the load, all working against the force of biasing spring 54 (if used).
[0058] Modulated Movement
[0059] The total displacement achieved and force acting on the load attached to movable member 12 , due to the recovery force of the active material component 32 , is illustrated by x 1 and F 1 in FIGS. 2 and 3 respectively. The displacement x 1 is indicated in FIG. 1 as movement of movable member 12 from a start position 60 to an intermediate position 62 . At the completion of the transformation of active material component 32 (or while transformation of active material component 32 is in progress if the transition temperature ranges of active material components 38 and 32 overlap. This is illustrated by the dashed line in FIGS. 2 and 3 with the overlap region between active material component 32 and active material component 38 represented by the interval t ov1 . Active material component 38 begins to transform pulling with it movable members 12 and 14 , and therefore the load. This causes an additional displacement of the load of x 2 and the force acting on the load is increased by Δ 2 , illustrated in FIGS. 2 and 3 . The displacement caused by activation of active material component 38 is indicated in FIG. 1 by movement of movable member 12 from intermediate position 62 to intermediate position 64 . Similarly as with the transformation of active material component 32 , at the completion of the transformation of active material component 38 (or while the transformation of active material component 38 is in progress if the transition temperature ranges overlap as illustrated in FIGS. 2 and 3 with the overlap region between active material component 38 and active material component 44 represented by the interval t ov2 ), active material component 44 begins to transform, thereby pulling with it movable member 12 and working against the opposing force of spring 58 . At the completion of the transformation of active material component 44 , there is an additional displacement of the load of x 3 and the force on the load is increased by Δ 3 , illustrated in FIGS. 2 and 3 . The displacement caused by activation of active material component 44 is indicated in FIG. 1 by movement of movable member 12 from intermediate position 64 to intermediate position 66 in FIG. 1 .
[0060] In FIGS. 2 and 3 , the increments in load displacement (x 1 , x 2 and x 3 ) and in force (F 1 , Δ 2 and Δ 3 ) appear equal for purposes of illustration only, but could be different depending on the characteristics of the active material components 32 , 38 and 44 and the biasing springs 54 , 56 and 58 and the kind of load that is attached to the movable member 12 . For example, it may be desirable to select the active material components such that some actuate quickly and achieve a relatively large displacement, followed by later actuation of another active material component to achieve a relatively small displacement. For example, active material components 32 and 38 may actuate at lower temperatures and may be selected to contract a relatively large amount, followed by actuation of active material component 44 which may actuate at a relatively high temperature and contracts a lesser amount. The actuation of the earlier actuated active material components may also occur more quickly than the actuation of the later actuated active material component to achieve a fast initial displacement followed by a slower movement to the final load position. In this way, the earlier actuated active material components accomplish coarse tuning or positioning of the load, while the later actuation fine-tunes the load position. Such an arrangement may simplify a control system designed to control the fixed position of the load. If all but one of the active material components actuate simultaneously to accomplish the coarse turning and the fixed active material component accomplishes fine tuning, the control system need only monitor the position of the load after the coarse tuning (i.e., monitor a single measurement of the initial, relatively large coarse-tuned displacement) to provide feedback for accurate positioning during fine tuning, rather than monitoring a series of displacements by actuation of active material components at different times that achieve the coarse tuning. This avoids the cumulative error associated with a series of discrete control measurements and also simplifies any overall control design. It is to be further appreciated that a load that linearly increases with displacement is assumed in the illustrations of FIGS. 2 and 3 .
[0061] The distinct or overlapping transformations of the different active material components 32 , 38 and 44 give rise to a modulated displacement profile of the load connected to movable member 12 . The result is that a larger displacement is obtained than with a single active material component or than with multiple active material components spanning from the distal face 48 of movable member 12 to the portion of anchor member 18 at which active material component 32 is connected. Furthermore, the recovery force is modulated as shown in the illustration of FIG. 3 . The stress on the active material components 32 , 38 and 44 continually varies with the actuation of each subsequent active material component (assuming no optional locking/latching mechanisms, as in the description below). It is preferable to ensure that the maximum stress in each active material component does not exceed the value required for acceptable performance. If the surrounding temperature decreases, the active material components 32 , 38 and 44 will be restored to their martensite phase lengths (i.e., the movable members will return to the positions shown in FIG. 1 ) due to the load and the biasing force of the respective springs 54 , 56 and 58 (if used), in order as temperature decreases.
[0062] Preferably the recovery force of active material component 44 is larger than that of active material component 38 which in turn is larger than that of active material component 32 . This is especially useful if locking mechanisms are used after the actuation of each active material component thereby isolating the active material component and allowing the next active material component to have a larger recovery force.
[0063] In FIGS. 2 and 3 , curves 70 and 72 , shown with solid lines, represent the load displacement profile and the load holding force profile, respectively, for the case where transformation of each active material component is completed before the subsequent one begins. Transformation of active material component 32 begins at time t=0, and is completed at time t=t 1 . There is a hold period until time t=t h1 when the temperature of the active material component 38 reaches its austenite start temperature, at which point transformation of active material component 38 begins and continues until time t=t h1 +t 2 . Again, there is then a hold period until time t=t h2 when active material component 44 reaches its austenite start temperature, at which point transformation of active material component 44 begins and is completed at time t=t h2 +t h3 . The flat sections of curves 70 and 72 describe the hold periods where no transformation is taking place.
[0064] For an embodiment where the compositions of the active material components 32 , 38 and 44 are such that the transformations overlap, the typical load displacement profile and load holding force profile are illustrated by curves 74 and 76 , respectively. For instance, in FIG. 2 , the overlap in the transformation of active material component 32 and active material component 38 occurs over time t ov1 . During this time, the rate of transformation of active material component 32 increases as active material component 38 begins to transform. At full transformation of active material component 32 the rate of transformation of active material component 38 continues as described earlier. A similar effect occurs over time t ov2 for the overlap of active material component 38 and active material component 44 . The description above is for illustrative purposes only and the response profile of each active material component, distinctly or during overlap, would generally depend on the composition of the active material component and the heat transfer process between the activation input trigger, whether an actuating field, fluid or current, and the active material component. For instance, the transformation rates shown as constant would generally be nonlinear.
[0065] Referring again to FIG. 1 , if active convective (fluid) heating were used instead of passive radiant heating, openings 80 , 81 , 82 and 83 would be provided in the respective anchor member 18 , and in movable members 14 , 16 and 12 . Arrows A illustrate the direction of fluid flow through the openings 80 , 81 , 82 and 83 for the general case where the same fluid flows past the different active material components 32 , 38 and 44 at the same time. Alternatively, if resistive electrical heating is used, the right end of each active material component could be connected to an electric lead, e.g., a positive electric lead, and the left end would be connected to the opposite electric lead, e.g., a negative electric lead, (i.e., at the anchors 52 ) with suitable insulation. Current could be supplied to the different active material components 32 , 38 and 44 in series or parallel, at the same time or in a defined sequence, depending on the desired force/displacement profile.
[0066] Referring to FIG. 4 , another embodiment of an active material actuator assembly 110 is illustrated. The active material actuator assembly 110 includes movable members 112 , 114 , and 116 , anchor member 118 and active material component 132 , 138 and 144 operable in like manner as similarly numbered components in FIG. 1 . A load 119 is connected to movable member 112 such that it is moved therewith. Each of the movable members 112 , 114 and 116 form a frame around an intermediate resilient portion which in this embodiment is bellows 113 , 115 and 117 , respectively. The bellows 113 , 115 and 117 are made of a suitable material, such as hydroformed metal, and are attached by any suitable means to the movable members 112 , 114 and 116 , respectively. The bellows are a flexible material that compresses in width as the active material components 132 , 138 and 144 contract and the movable members 112 , 114 and 116 move to the right. Biasing springs 154 , 156 and 158 may be placed in compression within respective movable members 116 , 114 and 112 to oppose the restoring force of the active material components 132 , 138 and 144 . The biasing springs could alternatively be placed in a similar position as springs 54 , 56 and 58 in FIG. 1 . As an alternative to the biasing springs 154 , 156 and 158 , the required bias could be built into all of the bellows 113 , 115 and 117 or only into bellows 117 to function as a return mechanism resisting the first-activated active material component 132 . Alternatively, the active material components used could have reversible shape memory effect in lieu of the biasing springs or bellows.
[0067] Automatic Activation
[0068] Automatic activation mechanisms could be integrated with the invention so that, assuming active activation, the activation input (i.e., actuating field, fluid or current), is transferred to a succeeding active material component when the preceding active material component reaches a predetermined level of change in a property such as a predetermined level of strain (e.g., a percentage of the maximum possible strain, for safety and/or durability), or when transformation is complete in order to maximize the output of the actuator assembly. That is, movement of a first moveable member via an activation input to a first active material component causes an activation input to a second active actuation mechanism to activate a second active material component. As illustrated in FIG. 5 , an active material actuator assembly 210 with movable members 212 , 214 , 216 and anchor member 218 includes an extension 290 on movable member 216 configured to contact extension 291 on anchor member 218 . (Movable member 212 is shown fragmented, but connects to a load similarly to movable member 112 of FIG. 4 .) At the completion (or at a predetermined level) of the transformation of active material component 232 , the extension 290 fits into and contacts extension 291 . This action allows the electric circuit (between positive electric lead 292 and negative electric leads 293 ) for active material component 238 to be completed, thereby allowing current to flow through the active material component 238 to cause its transformation to the austenite phase. Various ways could be used to ensure that the electric supply is well insulated from the rest of the active material actuator assembly 210 , for instance, by using a male/female connection system on the extensions 290 and 291 . In other alternative embodiments, the contact between the extension 290 and extension 291 need not directly complete the actuating electric circuit but can be used to trigger the sending of a signal to a control system (not shown) to supply current for the activation of active material component 238 in the case where this is desired. Similar extensions could be added between movable members 214 and 216 , to cause automatic activation of active material component 244 . In the case of active activation via convective heating, the contacting extensions could each have a hollowed conduit to allow the transfer of heating fluid through the conduits to heat a subsequent active material component when the extensions contact one another. For example, one end of one extension could cause a valve or orifice on the second extension to open, thereby allowing fluid flow which can be routed over the active material component.
[0069] Locking Mechanism and Releasing Mechanism
[0070] A locking mechanism or mechanisms could be integrated in an active material actuator assembly to lock adjacent movable members to one another to thereby achieve holding of the movable members in an actuated position during a power-off condition. In FIG. 6 , an active material actuator assembly 310 (shown only in part, but similar to any of the active material actuator assemblies of FIGS. 1 , 4 or 5 ), optional locking mechanism 394 connects movable member 316 to anchor member 318 at the completion of the transformation or at the required level of transformation (i.e., actuation) of an active material component (not shown) connected between movable member 316 and anchor member 318 , where these features operate as like numbered components in the active actuator assembly 210 , i.e., of FIGS. 1 , 4 or 5 . Similar mechanisms could be used between other pairs of adjacent movable members in the actuator assembly 310 . More flexibility is obtained in the level of load holding force obtained at each phase (i.e., at the time period associated with contraction of each active material component) since the total force at each stage could be more than the specified limiting force of the active material component in the preceding stage, as the previously activated active material component is isolated by the locking mechanism. For example, the load holding force could be greater than the specified limiting force of the active material component that connects movable member 316 to anchor member 318 after locking of the locking mechanism 394 as the load is then borne by the locking mechanism 394 . Any suitable locking mechanism could be used, including those described with respect to other active actuator assembly embodiments herein. For instance, in the assembly 310 shown in FIG. 6 , the arm 395 is attached to the movable member 316 and the extension 396 is attached to the anchor member 318 . As the transformation to the fully austenite phase of an active material component connected between movable member 316 and anchor member 318 progresses, movable member 316 is free to translate. Locking occurs when the arm 396 fits into the notch 397 in arm 395 as shown. During the movement to the left of movable member 316 (in the forward transformation to the martensite phase), the locking mechanism 394 is releasable via an upward force (indicated by arrow C) applied to downward extension 389 on extension 396 , compressing spring 399 and thereby pivoting arm 396 about pivot point B to allow its release from the notch 397 .
[0071] Exemplary Embodiment of An Alternative Active Material Actuator Assembly
[0072] Referring to FIG. 7 , another active material actuator assembly 410 utilizes a “train carts on a railroad” approach to achieve large linear displacement. The active material actuator assembly 410 includes movable members 412 , 414 and 416 , a fixed member 417 and an anchor member 418 , all of which are linearly aligned on a base member 421 . The movable members 412 , 414 and 416 slide or roll with respect to the base member 421 , similar to train cars on a railroad track. Although only three movable members are included in the actuator assembly 410 of FIGS. 7-9 , it should be understood that only two movable members or more than three may alternatively be used. The fixed member 417 and the anchor member 418 are secured to and do not move with respect to the base member 421 . The interface between the movable members 412 , 414 , 416 and the base member 421 could be any shape and configuration. In cross section, the base member 421 could be circular, oval, rectangular, triangular, square, etc., as long as the movable members 412 , 414 and 416 are configured with a mating shape to partially surround the base member. The interface can also be in a dove-tailed shape as shown in FIG. 7 . As an alternative approach, the base member 421 could have multiple slots, one for each movable member. It is therefore very easy to prevent overstretching and release each movable member at the appropriate location, as the distal end of a slot will always be the desired location for release of a movable member.
[0073] With regard to FIG. 7 , the movable members 412 , 414 and 416 are connected to the anchor member 418 via respective active material components 444 , 438 and 432 , respectively. The movable members 414 and 416 and the fixed member 417 have a set of aligned openings therethrough that allow active material component 444 to pass through to connect at a distal end to the movable member 412 and at a proximal end to the anchor member 418 , as illustrated. Movable member 416 and fixed member 417 have another set of aligned openings that allow active material component 438 to pass through to connect at a distal end to movable member 414 and at a proximal end to anchor member 418 . Finally, fixed member 417 has yet another opening therethrough that allows active material component 432 to pass through to connect at a distal end to movable member 416 and at a proximal end to anchor member 418 . The ends of each active material component 432 , 438 and 444 are crimped (or attached by any other suitable means such as welding or adhesive bonding) to maintain positioning. In an alternative design, the active material components 432 , 438 and 444 connect a respective extension (e.g., a rod or bar) extending from the respective movable member to an extension (e.g. a rod or bar) extending from the anchor member 418 rather than passing through openings in the movable members and the fixed member. To avoid bending and to increase fatigue life, the crimped ends of the active material components 432 , 438 , and 444 at the anchor member 418 are able to slide rightward during actuation. It is preferred that the bending momentum on the actuator assembly 410 induced by the active material components 432 , 438 and 444 is minimized by design choice of active material composition, cross-sectional area of the active material components and the structural strength of the base member 421 , the movable members 412 , 414 , 416 , fixed member 417 and anchor member 418 . The active material components 432 , 438 and 444 are shown in extreme extended positions, in a martensite phase, in which the movable members 412 , 414 and 416 will not move further to the left. The movable members 412 , 414 and 416 can either roll (via wheel(s) attached to respective movable member with or without bearings), slide or slide and roll on the base member 421 and are separated from each other by predetermined distances according to design. Optionally, multiple anchor members may be utilized so that the proximal ends of the active material components 432 , 438 and 444 can be at different longitudinal locations with respect to the base member 421 . A load or force that is to be moved by the active material actuator assembly 410 is either formed by the movable member 412 or is mechanically linked to a distal side of it. The load or force may be a weight or spring configured to act as a return mechanism (i.e., to create a force biased against contraction of the active material components 412 , 414 and 416 ).
[0074] When active material component 444 is activated (by supplying electrical current, as will be discussed below), the recovery or contraction force of the active material component 444 is greater than the total resistance of the load, and the movable member 412 is pulled to the right toward movable member 414 . When movable member 412 moves close to movable member 414 , they lock together via a locking mechanism such as that described in detail with respect to FIG. 8 . Next active material component 438 is activated to bring movable members 412 and 414 (locked together) to movable member 416 . When movable member 414 is close to movable member 416 , they lock together by locking mechanism such as that described with respect to FIG. 8 . Similarly, when active material component 432 is then activated, locked-together movable members 412 , 414 and 416 move to the right and movable member 416 is locked to the fixed member 417 by a locking mechanism as described with respect to FIG. 8 .
[0075] Locking Mechanism, Releasing Mechanism and Overstretch Prevention Mechanism
[0076] With reference to FIGS. 7 and 8 , each movable member 412 , 414 , 416 includes a locking mechanism. Locking mechanism for movable member 412 includes latch 495 A, pin 497 A and spring 499 A. Latch 495 A is able to enter a slot formed in movable member 414 and go further with pin 497 A passing through due to a slotted keyhole 496 A (see FIG. 7 ) in the front with a width slightly wider than the diameter of a pin 497 A retained in an opening within the movable member 414 . When movable member 412 touches movable member 414 , the keyhole 496 A in latch 495 A is exactly under the pinhead (i.e., a double-flanged head) of pin 497 A. With a little more shrinking of the active material component 444 (see FIG. 7 ), the latching pin 497 A will move downward due to the slope of ramped key 498 A and the biasing force of spring 499 A, to fall within the keyhole in latch 495 A. The uppermost flange on the pin 497 A is larger than the bottom hole of movable member 414 and thus rests above it to ensure that the pin 497 A rests in the latch 495 A to latch movable members 412 and 414 together. Movable member 414 (with movable member 412 latched to it) is locked to movable member 416 in like fashion as active material component 438 contracts, and movable member 416 (with movable members 412 and 414 locked to it) is locked to fixed member 417 in like fashion.
[0077] The releasing of the latches is in exactly the reverse order and will be described with respect to the release of movable member 412 from movable member 414 . When movable members 412 and 414 are pulled leftward in FIGS. 7 and 8 together by the load after actuation when conditions allow active material component 444 to return to its martensite phase, latching pin 497 A touches the slope in the key 498 A, rides up the slope, and the pin 497 A is moved upward until it slides into an upwardly extending stopper portion of the ramped key 498 A. The stopper portion acts as an overstretch prevention mechanism, preventing further movement to the left. At this point, the bottom of the lower flange of the double-flanged head of the pin 497 A (see FIG. 9 for a view of the double-flanged head) is flush with the top of the latch 495 A and therefore releases it. Similar latches, latching pins and ramped keys are utilized between movable members 414 and 416 and between movable member 416 and fixed member 417 .
[0078] The release of a movable member by releasing the latch must be done when the movable member is at the pre-contraction (original stressed) position. Otherwise, the active material component attached to the movable member may not be stretched enough for next activation and a more distal movable member (activated just prior) will not be able to lock to it. Therefore, the keys 498 A- 498 C are positioned in base member 421 at the desired start position of the movable members 412 , 414 and 416 or the position of fixed member 417 .
[0079] Since the latching pins 497 A and 497 B move together with the respective movable members 414 and 416 , they should not be blocked by keys 498 B and 498 C, respectively, when moving in the proximal direction. For example, in the fully locked position, the bottom of pin 497 A should be slightly higher than that the top of key 498 B. FIG. 9 illustrates that the shank portion of the pins 497 A, 497 B, and 497 C have respectively longer lengths and the keys 498 A, 498 B and 498 C are in order of descending height (key 498 A not shown in FIG. 9 ) so that the more distal movable member, will pass over the more proximal keys during return to the pre-contraction position. The sum length of each locking pin 497 A- 497 C and its matching ramped key 498 A- 498 C is the same for movable members 414 and 416 and fixed member 417 . Alternatively, to reduce the overall height in comparison with actuator assembly 410 , movable members with different widths can be used with keys offset along a horizontal transverse direction such that the keys can be of same height.
[0080] Although only one locking mechanism is shown here, any other existing mechanisms or new mechanisms can be adapted for use with any of the active material actuator assemblies described herein, such as a solenoid-based locking mechanism, a smart materials-based locking mechanism, a safety belt buckle-type latch design, or a toggle on-off design such as in a child-proof lock/release for doors or drawers or in a ball point pen. For example, the cart may have a keyhole, such as a T-shaped slot on a surface facing an adjacent cart. The adjacent cart may have a latch designed to fit in the upper portion of the T-shaped slot (i.e., the horizontal portion of the T-shape) and slide into the lower portion (i.e., the vertical portion of the T-shape) when the cart with the latch moves along a ramped track toward the cart with the T-shaped slot to lock the two carts to one another. The slope of the ramped track is designed to cause the relative vertical displacement between the two carts that enables latching and releasing of the latch from the T-shaped slot.
[0081] Other examples of locking and release mechanisms include a locking mechanism having a latch on one movable member that is configured to slide into a slot of an adjacent movable member. A separate release member can be actuated to push the latch out of the slot, thus releasing the two movable members from one another. The release member may be a roller attached to the end of a spring. The latch rolls along the roller when released, thus avoiding direct contact with the adjacent movable member during its release and reducing friction associated with the release movement.
[0082] Holding Mechanism
[0083] Power off holding is desirable for either full displacement (when the most proximal movable member 416 is locked to the fixed movable member 417 ) or at discrete displacement when a movable member is locked to the next movable member. Power off holding means utilizing a holding mechanism to hold a movable member at a post-activation contracted position, when the activation input is ceased (e.g., when the power is off if resistive heating is used or if temperature cools below the Austenite start temperature in the case of convective or radiant heating). For the embodiment shown in FIG. 8 , the key 497 A can be lowered down to lock movable members 412 and 414 together. By moving a sliding block 484 underneath the base member 421 along the longitudinal direction, the keys 498 A- 498 C will move off of raised bumps 485 on block 484 and be lowered down due to spring force exerted by springs 499 A- 499 C. With the keys 498 A- 498 C in a lowered position, even though the locking pin 497 A of movable member 414 slides on the slope of key 497 A during return of the active material component 438 to the martensite phase, key 497 A will not be able to push the locking pin 497 A far enough up in order for the lower surface of the lower flange of the pinhead to clear the keyhole opening in latch 495 A. Moving the sliding block 484 will cause holding of the movable members at the key associated with the most proximal of the movable members which have been moved or at the fixed member 417 if all of the movable members have already been moved to the right when the sliding block 484 is moved. To cancel the holding in order to release the movable members, the sliding block 484 can be moved back so that all the keys 497 A-C are pushed up. The vertical displacement of the keys via the sliding block 484 is small and the horizontal movement of the sliding block 484 can be achieved via many mechanisms, such as an electronic solenoid or a short SMA wire.
[0084] An alternative holding mechanism is illustrated in FIG. 7 with respect to movable member 412 . The alternative holding mechanism includes a pawl 486 and a ratchet portion 487 of the base member 421 . The pawl 486 allows the movable member 412 to be held at any position. To release the movable member 412 , the pawl 486 is pulled away (either rotated upward or pulled upward) from the ratchet portion 487 by a mechanism (not shown) such as an electronic solenoid or a short SMA wire.
[0085] Automatic Activation
[0086] The active material actuator assembly 410 can automatically mechanically activate the active material components sequentially to eliminate control logic and therefore reduce the cost. To realize this, the proximal ends of the active material components 432 , 438 and 444 at the anchor member 418 are all connected to the negative pole of the electric current supply, such as a battery (supply not shown) and the positive pole of the electric current supply is connected to separate electrical contact strips 491 A, 491 B and 491 C each located on the base member 421 between movable members (see FIG. 7 ). The bottom of each movable member 412 , 414 and 416 has its own specific electrical contact strip running fore and aft (in the same direction that the movable members 412 , 414 and 416 move) that is aligned with a specific electrical contact strip on the base member 421 . For example, referring to FIG. 7 , movable member 412 has electrical contact strip 490 A (shown with dashed lines) on a bottom surface thereof that is aligned with electrical contact strip 491 A (also referred to herein as a first active material activation mechanism) on the base member 421 . Movable member 414 has an electrical contact strip 490 B on a bottom surface thereof that is aligned with electrical contact strip 491 B (also referred to herein as a second active material activation mechanism) on the base member 421 . Movable member 416 has an electrical contact strip 490 C (shown with dashed lines) on a bottom surface thereof that is aligned with electrical contact strip 491 C on the base member 421 . The active material component connected to each distal movable member always maintains electrical contact with the electrical contact strip on the bottom of the movable member it is attached to. When a switch (not shown) is turned on to allow power flow from the electric current supply, active material component 444 will be in a closed circuit (the circuit including the electrical contact strip 490 A, the electrical contact strip 491 A, the active material component 444 and the power leads) causing active material component 444 to contract and move movable member 412 toward movable member 414 . After movable members 412 and 414 lock together, further movement of movable member 412 will cause electrical contact strip 490 A to be out of contact with electrical contact strip 491 A on the base member 421 and will cause the electrical contact strip 490 B at the bottom of movable member 414 to be in contact with electrical contact strip 491 B on the base member 421 . At this point, active material component 444 is in open circuit and active material component 438 is in closed circuit. Thus, an activation input to the second movable member, i.e., power from the electric current supply attached to the power leads, activates the active material component 438 to move the movable member 414 (and movable member 412 locked thereto). This “automatic activation” of the next active material component via movement of the previous movable member will be repeated until the movable member 416 reaches fixed member 417 . By using a contact switch on movable member 417 , the power can be turned off.
[0087] By locking each locking mechanism as each respective active material component 444 , 438 , and 432 contracts, the load operatively attached to the first movable member or the first movable member itself has a travel distance equaling the sum of the respective gaps (i.e., the open space along base member 421 ) between movable members 412 and 414 , between movable members 414 to 416 and between movable member 416 and fixed member 417 . To return the load back toward the distal end of base member 421 , the holding mechanism is first released (i.e., sliding member 484 is moved) if it was utilized, and the latch 495 C is released from the locking pin 497 C. As the active material component 432 is cooled and applies less resistance to stretching, the force of the returning mechanism also referred to as the load (e.g., a dead weight, a constant spring, a linear spring, a strut) is able to pull all the movable members 412 , 414 and 416 toward the distal end of the base member 421 . When movable member 416 is closer to its designed pre-contraction position, the latching between latch 495 B and locking pin 497 B is released by ramped key 498 B and therefore movable member 416 can be detached from movable members 412 and 414 . Similarly, movable member 414 will detach from movable member 412 and stop at the designed pre-contraction location due to the ramped key 498 A.
[0088] Large displacement can be achieved by the active material actuator assembly 410 , as many movable members can be added. The surface area between the movable members and the base member 421 (on which the movable members slide, roll or roll and slide) can be minimized to reduce friction losses. Finally, the returning force of the load can be matched very easily by a load holding force profile as the size or number of active material components, the composition and/or the transformation temperatures can be different for different movable members. Therefore, any returning mechanism such as strut, dead weight, linear spring, constant spring etc. can be chosen for convenience and performance. To have proper fatigue life and for safety and reliability, it is important that the active material components are not over-stretched by the returning mechanism.
[0089] In the embodiment shown in FIG. 8 , all of the movable members 412 , 414 and 416 , and the fixed member 417 have same sized components (the body of movable member or fixed member, the latches 495 A- 495 C, the setscrew at the top of each movable member 412 , 414 , 416 and fixed member 417 to adjust the tension of springs 499 A- 499 C) as shown in movable members 412 , 414 and 416 , as well as components of varying dimension (locking pin 497 A and ramped key 498 A) as shown in and discussed with respect to FIG. 9 .
[0090] FIG. 9 shows movable member 412 locked to movable member 414 which is locked to movable member 416 . Key 498 B acts as a power off holding mechanism as it is raised by bump 485 to interfere with pin 497 B. FIG. 9 illustrates the positioning just prior to automatic activation of active material component 432 (not shown in this cross-section) to move moveable member 416 to lock to fixed member 417 .
[0091] Exemplary Embodiments of Other Active Material Actuator Assemblies
[0092] Referring to FIG. 10 , an active material actuator assembly 510 includes a movable member in the form of a shaft 512 that is rotatable about a center axis 513 . The shaft 512 is concentric with an opening of a base member 517 and rotates therein. Optionally, a bearing may be placed between the shaft 512 and the base 517 to aid rotation. Referring to FIG. 11 , on an opposite side of the base 517 , a cam lobe 519 is connected for rotation with the shaft 512 . Referring again to FIG. 10 , an extension member, which may be referred to herein as a pin 521 extends from the shaft 512 such that it is offset from and parallel with the center axis 513 . Multiple active material components 532 , 538 , 539 and 544 , shown in the form of wires (but which may be belts, straps, strips, thin plates, chains or other shapes), have one end attached to the pin 521 . Active material component 532 is bent over pulley 523 A and further bent over pulley 525 A and extended toward the bottom of the base 517 where an end is attached to retaining pin 527 A. Active material component 538 is bent over pulley 523 B and extends toward the bottom of the base 517 where it attaches at an end to retaining pin 527 B. Active material component 539 is bent over pulley 523 C and extends toward the bottom of base 517 where it attaches to retaining pin 527 C. Active material component 544 is bent over pulley 523 D and further bent over pulley 525 B and extends toward the bottom of base 517 where it attaches to retaining pin 527 D. As an alternative to the pulleys 523 A-D and 525 A-B, gears may be used with the active material components 532 , 538 , 539 and 544 (or at least a nonactive wire portion connected thereto) being in the form of chains. The pulleys 523 A- 523 D (or gears if used instead of pulleys) are also referred to herein as sliding elements.
[0093] By bending the active material components 532 , 538 , 539 and 544 via pulleys 523 A-D and 525 A-B to extend in a common direction, packaging size is greatly reduced, with only one long dimension (the distance between the pulleys and the retaining pins at the bottom of the base member 517 ) accommodating the length of the active material components. Optionally, to avoid fatigue degradation due, directly or indirectly, to bending of the active material components, regular metal wires (or belts, strips, etc.) having long fatigue life may be used for any portion experiencing bending and active material composition may be used only for the portion from the respective pulleys 525 A, 523 B, 523 C and 525 B to the retaining pins 527 A-D (i.e., the portion that remains straight throughout the actuation cycle).
[0094] The base member 517 has multiple slots 529 A, 529 B, 529 C and 529 D extending therethrough. Extension portions of the pulleys 523 A, 523 B, 523 C and 523 D extend through the respective slots 529 A, 529 B, 529 C and 529 D so that a portion of each pulley is in contact with a cam surface 531 of the cam lobe 519 .
[0095] Resetting Cooled Active Material Components and Avoiding Stretching of Hot Active Material Components
[0096] The active material components 532 , 538 , 539 and 544 can be actuated in that order in a repeating series (or in the reverse order in a repeating series) to move the pin 521 and therefore rotate the shaft 512 to which a load is attached (or which constitutes a load). Both clockwise and counterclockwise rotation can be equally achieved in the actuator 510 by reversing the order of actuation. To avoid overstretching, to decrease resistance to stretching of a just actuated and still hot active material component and to decrease response time, the pulleys 523 A- 523 D are designed to move in the respective slots 529 A- 529 D according to the cam surface 531 (i.e., the cam profile) of the cam lobe 519 , shown in FIG. 11 . In FIG. 11 , pulleys 523 C and 523 D are shown on a larger arc of the cam surface 531 and in the farthest position relative to the center axis 513 . In contrast, pulleys 523 A and 523 B are on a smaller arc and in the nearest position relative to the center axis 513 . The pin 521 is nearest to pulley 523 C (see FIG. 10 ), active material component 539 (referred to in the claims as the first active material component) has just been actuated and it is time to activate active material component 544 (referred to in the claims as the second active material component). During the contraction of active material component 544 , pulley 523 D will sit on the: larger arc and remain a constant distance to the center axis 513 . The pin 521 will be pulled and moved toward pulley 523 D. Pulley 523 C will move toward the center axis 513 because it will be on the smaller arc when pin 521 moves near pulley 523 D. Due to this inward motion of pulley 523 C sliding in slot 529 C toward the center axis 513 , the previously actuated and potentially not yet cooled active material component 539 will not be further stretched and will apply no resistance to the work done (i.e., to the rotation of shaft 512 ) by actuation of active material component 544 provided the portion of active material component 544 (or wire if that portion is not active material) between pulley 523 C and retaining pin 527 C is barely stretched. This portion of active material component 544 between pulley 523 C and retaining pin 527 C will change in length only a minimal amount if it is nearly perpendicular to the longitudinal direction of the slot and if it is much longer than the longitudinal dimension of the slot. FIG. 10 is schematic in nature and the dimensions are not to scale. Positions and shapes of the slots and positions of the retaining pins are also schematic. In addition, additional pulleys (not shown for simplicity) may slide with pulleys 523 A-D and help with the routing of the active material components. Although pulley 523 B sits on the same smaller arc during this period, the cooled active material component 538 is stretched since pin 521 moves near to pulley 523 D from a position near pulley 523 C. Pulley 523 A increases its distance from the shaft center during this period since the rotating cam 519 causes it to slide in slot 529 A and move to a larger arc, maintaining the length of the active material component 532 between pin 521 and pulley 523 A. When activation of active material component 544 is complete, active material component 532 is in the right position and ready for a subsequent activation.
[0097] Within the scope of the invention, the number of active material components is not limited to four. A rotational motor as in FIGS. 10 and 11 could haven only three or more than four active material components. Furthermore, the slots 529 A-D are not limited to the shape shown. A center line running the length of each slot does not necessarily pass through the shaft center and need not be straight.
[0098] Automatic Activation
[0099] Sequential automatic activation by the mechanical rotation of the shaft 512 can be utilized to allow the elimination of control logic to activate the active material components 532 , 538 , 539 and 544 sequentially and therefore potentially reduce cost. The four individual ends of the active material components connected to pins 527 A through 527 D can be connected to the negative pole of a battery (not shown). Referring to FIG. 12 , the positive pole of the battery is connected to a switch 589 and then connected to an electrical brush 533 on the cam surface 531 of cam 519 . An electrical contact strip 535 extends partially around the cam surface 531 . The contact strip 535 is in electrical contact with a circular electrical strip 537 on the cam surface 531 that touches the brush 533 at all times. On the surface of each pulley 523 A, 523 B, 523 C and 523 D that touches the cam surface 531 , there is a circular electrical contact strip 541 A, 541 B, 541 C and 541 D, respectively, positioned to be sequentially in contact with the contact strip 535 as the shaft rotates. The circular electrical contact strip 541 A- 541 D on each pulley 523 A- 523 D is electrically connected to the surface area of the pulley that the respective active material component is touching (or that a non-active material portion, e.g., a metal portion of a wire, strip, chain or belt that is connected to an active material portion, as explained above, is touching). All surface areas of the cam surface 531 and of the pulleys 523 A- 523 D are non-conducting except those mentioned above.
[0100] When the switch 589 is closed (i.e., by turning on the actuator assembly 510 ), electrical power runs to the full circle electrical contact strip 537 and to whichever one of the pulleys 523 A- 523 B is then positioned in contact with the contact strip 535 (pulley 523 C in FIG. 12 ). The active material component connected with that pulley is activated to move the pin 521 . Movement of the pin 521 due to actuation of that active material component, as described above, will rotate the cam 519 , causing the next sequential one of the pulleys to be positioned in contact with the electrical contact strip 535 to activate the active material component connected thereto (and will cause the previously actuated active material component to move out of contact with the contact strip 535 ). The contact strip 535 may extend 90 degrees or so around the cam surface such that only one of the four pulleys 523 A- 532 D is in contact with the contact strip 535 at any given time. Alternatively, the contact strip may extend less than 90 degrees, to allow a longer cooling period between activations, or greater than 90 degrees such that there is some overlap of activation of the active material components. The portion of the cam profile 519 about which the contact strip 535 extends may be longer if only three active material components and corresponding pulleys are used, or shorter if more than four are used. In general, the portion over which the contact strip 535 extends is cam-profile dependent.
[0101] Power off holding of the active material actuator assembly 510 is desirable. It can be realized via the locking mechanism (and corresponding release mechanism) similar to that described with respect to the active material actuator assemblies 410 above or a ratchet mechanism.
[0102] Another embodiment of an active material actuator assembly 610 operating as an incremental rotational motor is shown in FIG. 13 . A shaft 612 with an extension or pin 621 is concentric with a hole through a cylindrical housing 617 and rotates with or without the help of a bearing. Active material components 632 , 638 , 639 and 644 are attached to the biased pin 621 at one end, bent over pulleys 623 A-D and 625 A-D and attached to retaining pins at the other end of the cylindrical housing (pins not shown, but FIG. 14 shows the active material components in fragmentary view extending toward the pins). The pulleys 623 A-D and 625 A-D sit on sliders 643 A-D that slide in slots 629 A-D of the cylindrical housing 617 . The active material components 632 , 638 , 639 and 644 can be activated sequentially and therefore rotate the shaft 612 with respect to the cylindrical housing 617 . Since all the active material components 632 , 638 , 639 and 644 are bent (via the pulleys 625 A-D) to extend in the axial direction of the shaft 612 , sufficiently-sized active material components able to achieve large displacement (e.g., active material components of a sufficient length to achieve adequate displacement of the movable member via contraction of each active material component) are enabled while packaging size is minimized. Optionally, to avoid fatigue degradation due to bending of active material components, non-active material portions (e.g., regular metal wire) having long fatigue life can be substituted for any portion of the active material components experiencing bending and active material can be used only in the portion that remains straight throughout the actuation cycle, i.e., the portion nearly parallel to the axial direction of the shaft 612 .
[0103] The sliders 643 A- 643 D ride on a cam lobe 619 of the shaft 612 . The cam profile 631 (shown in the FIG. 14 ) allows the slider to which the just-actuated active material component is operatively connected to move toward the center of the shaft 612 and therefore prevents being pulled by the next-actuated active material component. The cam profile 631 therefore utilizes the contraction force of the active material components more efficiently (i.e., utilizes the force to turn the shaft rather than to work against restrictive force of the just-actuated active material component), allows more cooling time before stretching of a previously actuated component, and decreases the cycle time of the actuator assembly 610 . The cam profile 631 can also be made to avoid unnecessary overstretching of the active material components. In FIGS. 13 and 14 , each active material component is only stretched by the opposite actuated active material component (i.e., active material component 644 is stretched when active material component 638 is actuated and vice versa, and active material component 639 is stretched when active material component 632 is activated and vice versa) and the amount of stretch is the same as the amount needed to pull the pin 621 and rotate the shaft 612 when it is actuated.
[0104] Automatic activation is possible which will eliminate the use of control logic to activate wires sequentially and therefore reduces the cost. By providing an electrical contact strip only partially extending around the cam surface similarly to electrical contact strip 535 in the embodiment of FIG. 12 , the respective active material components will be activated sequentially as the shaft 612 rotates. Power off holding is desirable and it can be realized via a ratcheting or locking and releasing mechanisms, as described with respect to other embodiments herein.
[0105] Note that in the active material actuator assembly 610 , the number of active material components is not limited to four. There could be only three active material components or more than four. The slots 629 A-D are not limited to the configuration shown. The center line of the slots does not necessarily pass through the shaft center and is not necessarily straight. In addition, both clockwise and counterclockwise rotation can be equally achieved in the said mechanism. Moreover, to reduce response time and decrease cooling time while maintaining required force, several thinner SMA components can be used in place of each active material component (e.g., several thinner SMA wires in place of each single SMA wire) to connect the distal end.
[0106] While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims. | Active material actuator assemblies are provided that enable simplified control systems and faster actuator cycle times. A movable member is provided that has multiple active material components operatively connected to it. The active material components are separately selectively activatable for moving the movable member. Movement of the movable member via activation of a first of the active material components triggers activation of the second active material component to further move the movable member. Alternatively or in addition, previously activated active material components are protected from undesired stretching during activation of another active material component or, when desired, an active material component may be reset via activation of another of the active material components in order to prepare it for subsequent activation. | 7 |
BACKGROUND OF THE INVENTION
Environmentalists have raised a consciousness concerning the contamination of our environment with unsightly and virtually uncontrollable depositing of waste and debris usually at designated landfill sites. This debris may come from many sources including demolition sites, razing or gutting of existing buildings, land clearing areas, manufacturing and construction sites to mention a few.
One of the major problems and disadvantages that exist with respect to current landfill, sites include fires, many of which are fanned by underground tunnels of air caused by the bulkiness and large size of the debris. Fires of this type are generally very difficult to contain and to extinguish.
Another serious problem with respect to landfill sites is the slowness and the uncontrollable nature of the degradation of the debris also caused by the bulkiness and large size of many of the items deposited at these sites.
There have been attempts to solve the handling of waste and the landfill problems, but most have been ineffectual. For example, at many building construction and demolition sites, compactors often times receive the building debris. While compaction of this material does to some extent reduce its bulkiness, it does not reduce the size or bulkiness of the individual items. At best, compaction merely reduces the amount of air space. Compaction of debris is not an effective solution to landfill problems.
Certain machinery has been proposed for reducing the size of debris, but these machines have their limitations, particularly in terms of efficiency, power requirements, lack of speed, and in many instances, the inability to handle relatively large pieces of debris. Some of the known existing machinery includes "SLASHBUSTERS" offered by D & M Machine Division Inc., Montesano, Washington, "STUMPMASTER" marketed by Stumpmaster, Inc., Rising Fawn, Georgia and the M80 Grapple Loading Portable Universal Refiner marketed by Universal Refiner Corporation, Montesano, Washington. Augers have also been proposed but usually require too much power and cannot reduce relatively large size waste materials. Machines of the foregoing type only have limited application at best and are unable to completely resolve the landfill problems which require the ability to handle all types and sizes of debris and reduce it to a size manageable for landfill areas that would enhance the biodegradation process.
SUMMARY OF THE INVENTION
The principal object of the present invention is to provide apparatus for reducing building waste and debris to a size acceptable for use as fill material for landfill sites, so that it can be readily decomposed, the resultant material being more environmentally acceptable.
Another object is to provide a material reducing apparatus of the foregoing type requiring less power for more effective shredding and grinding action.
A further object is to provide a material reducing apparatus of the foregoing type that possess a "live floor" that keeps chewing and reducing debris to an acceptable size.
An important object is to provide a material reducing machine of the foregoing type that is capable of accepting any type material including any metallic, plastic and rubber objects, including objects of relatively large size.
Another important object is to provide a material reducing machine that is mobile, can be transported on a trailer and can be located at a building or demolition site or a landfill for receiving materials at these locations and reducing it in size; and such reducing machine is so effective that a pile of loose material discharged by this machine is relatively more sightly and acceptable to environmentalists.
Objects and advantages will become apparent from the following detailed description, which is to be taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a material reducing apparatus incorporating the teachings of the present invention in which debris is loaded into the top of hopper from above;
FIG. 2 is an enlarged longitudinal sectional view of the apparatus with certain parts removed;
FIG. 3 is an end view thereof;
FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG. 2;
FIG. 5 is a perspective view showing the apparatus handling debris on the ground; and
FIG. 6 is a longitudinal section of the apparatus shown in FIG. 5 with certain parts removed.
DETAILED DESCRIPTION
In the drawings, the material reducing apparatus 10 includes a hopper 12 for receiving debris and waste material, which as shown in FIG. 1 may be loaded from the top. The hopper is provided with side walls 14 and 16, welded or otherwise secured to the boom 18 rotatably mounting an endless chain 20, which defines a movable floor of the hopper 12. In the embodiment of FIG. 1 front end 22 is open. By keeping the front end open, material that cannot be shredded or ground could very easily be removed from the hopper 12 by simply reversing the rotation of the chain 20 in the manner to be described. On the other end, the front end 22 may be closed and capable of being moved up and down vertically by a hydraulically operated piston of conventional construction. It is also contemplated that this front wall 22 can also be pivotal down towards the base of the hopper 12 to serve as a compacting member for the debris in the hopper 12 to facilitate its reduction. Compaction of the material travelling on the chain 20 expose it more to the grinding and shredding action of the cutting bits on the chain 20 as will become more evident shortly.
The rear end 24 of the hopper 12 is movable up and down vertically by means of a hydraulic cylinder 26, which for convenience may have its cylinder anchored to a cross-bar 28 and its piston rod attached to the movable plate 24. The base of the plate 24 is provided with a shear bar 30 of hardened material that will cooperate with the chain 20 in reducing the debris by a chewing type action by interposed cutting bits in a manner to be described in detail shortly.
The chain 20 is provided with plates 32 on which are mounted blocks 34 which receive bits 36. These bits may be of any suitable type for the material reducing operation selected. In certain applications, flat cutter bits have proven to be satisfactory.
The construction and operation of the boom 18, chain 20, blocks 34 and bits 36 may be of the type utilized in the Vermeer T-850 Trencher manufactured and marketed by Vermeer Manufacturing Company, Pella, Iowa. The principal difference in the construction and operation is that the chain according to the present invention operates in a clockwise direction as shown in FIGS. 2 and 6 with the blocks 34 and bits 36 facing in a rearwardly direction towards the shear bar 30 which is opposite to that normally employed in the trencher.
In operation, the debris that is loaded into the hopper and engages with the bits 36 on the chain 20 is immediately exposed to a chewing or shredding operation. The material reduction to the proper selected size is finalized when this material passes under the shear bar 30. The size of the reduction in material depends on the position of the shear bar 30 relative to the bits 36. The raising and lowering of plate 24 adjusts the distance between the bottom edge of shear bar 30 and the chain 20 with the teeth 36 cooperating in arriving at the desired size of material to be reduced.
In order to further enhance the shredding and reduction operation, the bottom of the shear bar 30 may be provided with teeth 38 which may be similar to teeth 36 but facing in the opposite direction. These teeth 38 will cooperate with teeth 36 to further reduce the debris to the desired size and also renders the shredding operation more efficient.
As will also be noticed, the boom 18 is inclined slightly towards the base of the shear bar 30 to further drive the debris into the final shredding zone immediately beneath the shear bar 30. The urging of the material in this direction is continuously being down as a result of the continuous movement or rotation of the chain in a clockwise direction, driving material into the cutting zone.
An operator is advantageously located in the cabin 40 within which are located the controls for chain 20, the hydraulic cylinder 26 and a hydraulic cylinder 32 which facilitates the raising and lowering of the boom 18 for purposes of which will become evident shortly. In addition the operator will be able to maneuver the apparatus 10 from one location to another through the operation of tracks 44 and 46. A movable conveyor 48 advantageously receives the shredded material from the chain 20 that passes beneath the shear bar 30 and transfers it in the disclosed embodiment rearwardly to the selected site for eventual removal and relocation to another place. As is the case with the trencher identified in the above all moving parts may be driven from the diesel engine 50.
Referring now to FIGS. 5 and 6, it will be observed that in certain instances it may be desirable not to top load the hopper 12 but to lower boom 18 and back the trailing end of the chain 20 into a pile of debris or selected part of a landfill site to further reduce the debris in size. Towards this end, the rotation of the chain 20 with the cutter bits 36 thereon will act to dislodge and lift debris on to the top surface of the chain 20. As the desired amount of debris is reduced in size the operator merely maneuvers the material reducing apparatus 10 by maneuvering the tracks 44 and 46 in a conventional manner.
In this embodiment, the debris that is reduced in size instead of being conveyed by conveyor 48 to a location at the rear end of the apparatus 10 as in FIGS. 1-4 is moved laterally on a conveyor 52 that receives the reduced debris. Lateral conveyors of this type, their construction and operation appear on the commercially available trencher identified in the above.
As previously explained, only certain size materials will be permitted to go under the shear bar 30 and its height relative to the chain 20 will determine the size of the material passing through this reducing zone. The efficiency of the shredding or reducing operation is determined by the cutter teeth 36 either alone or in cooperation with the stationary cutter bits 38. From time to time there will be objects that will be picked up by the chain 20 incapable of being ground or shredded. In this case, the operator merely reverses the rotation of the chain 20 to effectively remove this object from the hopper and from the reducing zone.
In actual practice, the reducing of the debris occurs throughout the entire floor or top surface of the chain 20 because of the teeth appearing thereon start the chewing or reducing operation along the entire length of the chain with the final shredding occurring at the shear bar.
Another significant advantage of the present invention is the ability to replace the cutter bits 36 and when worn or when a different reducing action is desired which may dictate that a cutting tool or a busting tool be employed. Another significant advantage is the fact that the apparatus can handle mixed variety of debris without changing the instruction or operation thereof. Compared to prior art apparatus the apparatus of the present invention is many times faster in its reducing operation because the area and speed of cutting is greater and it possesses a larger cutting surface. Furthermore the present invention takes advantage of utilization of a chain with cutting tools which is a proven cutting technique as well as a technique for moving material.
The sloping nature of side walls 14 and 16 contribute to and facilitate the proper feeding of the debris downwardly on to the chain 20.
There are many different forms of loading of the hopper 20 that are contemplated and it should be understood that many variations thereof are possible including chutes, bucket loaders, conveyors, feed rollers and essentially any other type of feeding mechanism that places debris on the chain 20 and forces it into the shearing area.
While the contemplated engine 50 is of the type employed in the trencher identified in the foregoing, because of the power available, if it is found that less power is needed, smaller engines may be employed.
Thus, material reduction and shredding operation of the present invention enhances the degradation of the waste being handled. In actual practice the original volume of waste is reduced to only a small percentage of the original volume and two inch reduced material has been obtained in specific application.
As explained the apparatus of the present invention can reduce essentially all waste material whether it be tree stumps, wood, paper, plastic, rubber or metallic products, demolition waste, mill waste, log yard waste and cut stock waste.
Thus the several aforenoted objects and advantages are most effectively attained. Although several somewhat preferred embodiments have been disclosed and described in detail herein, it should be understood that this invention is in no sense limited thereby and its scope is to be determined by that of the appended claims. | A material reducing apparatus includes a hopper having a pair of opposed sides, a front end and a back end. The back end has a top and bottom and a shearing edge at the bottom. A chain with bits forms the floor of the hopper. The chain is on a boom. Drive means drives the chain so that the bits move towards the shearing edge. The moving bits cooperate in reducing material conveyed on the chain and cooperate further with the shearing edge to reduce the material to a predetermined size. | 1 |
RELATED APPLICATIONS
This application claims priority under 35 USC § 119(e) from U.S. Provisional Application Ser. No. 60/414,289, filed 27 Sep. 2002, entitled “Multilayer Substrate,” the entirety of which is incorporated herein by reference.
This application is a continuation-in-part claiming priority under 35 USC § 120 from U.S. patent application Ser. No. 10/331,186, filed 26 Dec. 2002, entitled “Multilayer Substrate,” the entirety of which is incorporated herein by reference.
This application related to U.S. patent application Ser. No. 10/038,276, filed 31 Dec. 2001, entitled “Sensor Substrate and Method of Fabricating Same,” the entirety of which is incorporated herein by reference.
BACKGROUND
1. Field of the Invention
Embodiments of the invention relate to semiconductor device fabrication, and, in particular, to the formation of multilayer wiring substrates on which integrated circuits or discrete devices are mounted.
2. Description of Related Art
A variety of mounting structures are known for electronic circuits. Multi-chip modules and hybrid circuits are typically mounted on ceramic substrates that include metallic conductors for interconnecting the components, and the components are typically sealed within a metal or ceramic casing. Complex hybrid circuits typically require equally complex interconnection structure. In such instances it is common to utilize a multilayer substrate comprised of multiple layers of conductors sandwiched between multiple layers of dielectric material. Multilayer substrates are conventionally fabricated by lamination techniques in which metal conductors are formed on individual dielectric layers, and the dielectric layers are then stacked and bonded together.
Various conventional lamination techniques are known, however each has limitations that restricts its usefulness for producing multilayer substrates. High temperature ceramic co-fire (HTCC) lamination techniques form conductors on “green sheets” of dielectric material that are bonded by firing at temperatures in excess of 1500 degrees C. in a reducing atmosphere. The high firing temperature precludes the use of noble metal conductors such as gold and platinum. As a result, substrates formed by high temperature processing are limited to the use of refractory metal conductors such as tungsten and molybdenum, which have very low resistance to corrosion in the presence of moisture and are therefore not appropriate for use in harsh environments.
Low temperature ceramic co-fire (LTCC) techniques also utilize green sheets of ceramic materials. Low-temperature techniques do not require the use of a reducing atmosphere during firing and therefore may employ noble metal conductors. However the dielectric materials used in low-temperature processes are generally provided with a high glass content and therefore have relatively poor resistance to environmental corrosion, as well as a relatively low dielectric constant and relatively poor thermal conductivity.
Thick film (TF) techniques form multilayer substrates by firing individual dielectric layers and then laminating the layers to form a multilayer stack. However, thick film techniques require the use of relatively thick dielectric layers and thus it is difficult to produce a thin multilayer substrate using thick film techniques. Thick film dielectrics also have relatively low dielectric constants, relatively poor thermal conductivity, and poor corrosion resistance.
In addition to the problems listed above, the conventional lamination techniques cannot use green sheets of less than 0.006 inches in thickness because thinner green sheets cannot reliably survive necessary processing such as drilling or punching of via holes. Also, because the designer has limited control over the thickness of individual green sheets, the number of layers of the multilayer substrate is often limited according to the maximum allowable substrate thickness for the intended application. Thus, where a thin multilayer substrate is desired, lamination techniques generally do not provide optimal results.
In addition, the firing required in the conventional lamination techniques can cause shrinkage in excess of 10% in both dielectric and conductor materials, which can produce distortions that result in misalignment of vias and conductors after firing. While shrinkage effects can be addressed to some extent during design for substrates having a modest interconnect density, the design process is made more time consuming and a significant reduction in yield may occur in applications with higher densities and tighter dimensional tolerances.
The conventional technology is therefore limited by several restrictions. All of the aforementioned techniques are limited with respect to the minimum substrate thicknesses that can be produced, and the various firing requirements of the aforementioned techniques prevent the use of materials that are desirable for circuit structures. All of the aforementioned techniques also suffer from shrinkage during firing that causes alignment problems.
SUMMARY OF THE INVENTION
In accordance with embodiments of the invention, a multilayer circuit substrate is comprised of a base substrate and one or more additional dielectric and conductive thin films formed over the base substrate by vacuum deposition methods. The vacuum deposited dielectric layers are significantly thinner than the dielectric layers used in conventional lamination techniques, allowing for the formation of multilayer circuit substrates that are significantly thinner than those formed by conventional lamination techniques. Because vacuum deposited dielectrics are deposited in an “as-fired” state that undergoes essentially no shrinkage during subsequent processing, yield reduction due to misalignment is significantly reduced or eliminated. In addition, vacuum deposition techniques do not impose limitations on the types of conductors or dielectric materials that may be employed, enabling the use of a wide variety of materials with highly tunable properties. Vacuum deposition techniques also produce hermetic layers that facilitate the production of highly reliable substrates.
In accordance with further embodiments of the invention, deposited dielectrics may be patterned through the use of sacrificial structures that may be removed using highly selective etch chemistry. The sacrificial structures are preferably formed using a high precision shadow mask that allow dielectric patterns to be precisely registered to underlying structures and thus enabling high interconnect densities and narrow dimensional tolerances not achievable by conventional lamination techniques.
In accordance with further embodiments of the invention, patterning techniques such as shadow masking, chemical etch and photoresist lift-off may be used for patterning conductive materials. Conductors may therefore be precisely aligned with underlying structures and formed with linewidths not achievable by conventional lamination techniques.
In accordance with further embodiments of the invention, hermetic vias may be formed in the dielectric base substrate by forming successive thin layers of a conductive material on the sidewalls of a via hole using a dilute conductive ink, followed by formation of a conductive plug using a concentrated conductive ink. The conductive material in the via is then sintered to form a unitary body, producing a hermetic via without shrinkage of the surrounding dielectric.
In accordance with one embodiment of the invention, a multilayer circuit substrate is characterized by a dielectric base substrate having conductors formed thereon, and at least one layer of a patterned vacuum deposited thin film dielectric overlying the conductors. In various implementations, multiple layers of conductors and deposited dielectrics may be used, multiple layers may be formed on both sides of the base substrate, and the base substrate may include hermetic vias. It is preferred that the deposited thin film dielectrics are patterned using sacrificial structures formed by shadow mask deposition.
In accordance with another embodiment of the invention, a multilayer circuit substrate for a multi-chip module or a hybrid circuit is produced. Initially a dielectric base substrate is provided. Conductors are then formed on the base substrate, preferably by patterning of a blanket layer of conductive thin film deposited by a vacuum deposition method. Sacrificial structures are then formed on the base substrate and conductors. The sacrificial structures define areas of the base substrate and conductors that are to be protected during subsequent dielectric deposition. The sacrificial structures are preferably formed by shadow mask deposition. A thin film dielectric layer is then vacuum deposited on the base substrate, the conductors and the sacrificial structures, and the sacrificial structures are removed to leave a patterned deposited thin film dielectric layer on the conductors and the base substrate. Further processing such as forming additional conductor layers and dielectric layers or mounting of an electronic component to the substrate may be performed.
DESCRIPTION OF THE DRAWINGS
FIGS. 1 a , 1 b , 1 c , 1 d , 1 e , 1 f , 1 g and 1 h show structures formed during fabrication of a hermetic via in accordance with a preferred embodiment;
FIGS. 2 a , 2 b , 2 c , 2 d , 2 e , 2 f , 2 g , 2 h , 2 i , 2 j and 2 k show structures formed during fabrication of a multilayer circuit substrate and circuit structure in accordance with the preferred embodiment; and
FIG. 3 shows a process flow encompassing the processing of FIGS. 2 a – 2 k and alternative processing.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
A preferred embodiment of a method for producing a multilayer circuit substrate is now described in the context of production of a hermetic blood glucose sensor circuit. It should be understood that the processing performed in the preferred embodiment represents one implementation of the invention and that the techniques of the invention have a variety of alternative applications, examples of which are provided after the description of the preferred embodiment.
FIGS. 1 a – 1 h show structures formed during processing in accordance with the preferred embodiment to form a hermetic via in a dielectric base substrate. While the processing of FIGS. 1 a – 1 h illustrates a single via, it will be appreciated that multiple vias may be produced simultaneously using the illustrated techniques.
FIG. 1 a shows a cross-sectional view of a portion of a dielectric base substrate 10 . The base substrate is preferably a sheet of 96% purity alumina (Al 2 O 3 ) that is pre-fired such that shrinkage will not occur during subsequent processing. The preferred embodiment utilizes a two inch by two inch substrate having a thickness of approximately 0.010 inches.
FIG. 1 b shows the base substrate of FIG. 1 a after laser drilling of a via hole 12 . Annealing is preferably performed after laser drilling to reduce imperfections caused during drilling. The use of laser drilling coupled with the techniques described below for precise registration of overlying materials enables the production of ultra-small vias with via densities up to the limits of laser processing. In accordance with the preferred embodiment, vias may be formed with diameters of 0.002 inches and a spacing of 0.006 inches, whereas conventional drilling and tape punch methods as well as shrinkage limit vias produced in HTCC and LTCC substrates to diameters of approximately 0.005 inches and spacings of approximately 0.015 inches.
FIG. 1 c shows the structure of FIG. 1 b after a dilute conductive ink 14 is introduced into the via hole 12 of the base substrate 10 . The conductive ink 14 typically comprises a slurry of a particulate noble metal such as gold or platinum suspended in an organic binder that is eliminated during later thermal processing. In accordance with the preferred embodiment, the ink applied to the substrate is diluted from its typical paste-like commercial consistency to a more flowable consistency through mixture with a solvent. The conductive ink 14 is preferably introduced to the via hole 12 by a screen printing technique using a metal screen having apertures corresponding to via holes 12 formed in the base substrate 10 . The metal screen is aligned with the base substrate, conductive ink is coated on a surface of the metal screen, and the ink is then forced through the apertures in the screen by dragging with a rubber blade.
FIG. 1 d shows the structure of FIG. 1 c after application of a vacuum to the via hole 12 . The application of the vacuum causes the conductive ink to form a thin conductive coating 16 that adheres to the sidewalls of the via hole 12 without bubbles or voids. Application of the vacuum is typically followed by low temperature firing in a range of 100–200 degrees C. to remove solvent from the conductive ink, and then by high temperature firing in a range of 850–950 degrees C. to burn out the organic binder from the conductive ink and to fuse the conductive particles.
FIG. 1 e shows the structure of FIG. 1 d after formation of multiple additional thin coats 16 of conductive material on the via hole 12 sidewalls through further applications of dilute conductive ink followed by application of vacuum and firing. As seen in FIG. 1 e , each successive layer of conductive material reduces the width of the opening between the sidewalls of the via hole 12 .
FIG. 1 f shows the structure of FIG. 1 e after formation of a plug 18 in the via using a conductive ink that is undiluted or substantially less dilute than the ink used for formation of the thin sidewall layers 16 . In some instances the formation of the plug may be followed by formation of one or more additional layers 20 of ink to fill any depressions at the ends of the via. The conductive ink is fired after each of these applications.
FIG. 1 g shows the structure of FIG. 1 f after removal of residual conductive material from the surface of the base substrate 10 . Residual conductive material is typically removed by a lapping process in which the base substrate 10 is held in a fixed position while an abrasive material is moved against its surface. Lapping may be followed by chemical etching to remove any remaining conductive material from the base substrate surface.
FIG. 1 h shows the structure of FIG. 1 g after sintering at a temperature of approximately 1000–1200 degrees C. to bond the individual conductive particles of the conductive ink layers into a monolithic via conductor 22 . After sintering, the via is subjected to helium leak testing to confirm the hermeticity of the via.
FIGS. 2 a through 2 k show structures formed during processing in accordance with the preferred embodiment for producing a blood glucose sensor using a base substrate having vias formed in accordance with the processing of FIGS. 1 a – 1 h . Each of FIGS. 2 a through 2 k provides a top plan view, a cross-section taken along line A–A′ of the top plan view, and a bottom plan view of a section of a substrate upon which processing is performed in accordance with the preferred embodiment.
FIG. 2 a shows a base substrate 30 having a plurality of hermetic vias 32 extending between its major surfaces. The base substrate 30 is preferably a substrate of the type used in the processing of FIGS. 1 a – 1 h , and the hermetic vias are preferably formed in accordance with the processing of FIGS. 1 a – 1 h.
FIG. 2 b shows the structure of FIG. 2 a after formation of welding pads 34 on the top surface of the substrate. The welding pads 34 provide connection points for external wires to the circuitry that will be mounted on the substrate. The welding pads of the preferred embodiment are formed by screen printing using a platinum conductive ink, however in alternative embodiments contacts may be formed by other techniques that are consistent with the requirements of the joining process.
FIG. 2 c shows the structure of FIG. 2 b after formation of patterned conductors 36 on the top surface of the base substrate 30 . The conductors 36 are preferably formed of consecutive layers of titanium, platinum and titanium that are patterned by a photoresist lift-off process. In the lift-off process, a photoresist layer is patterned to form a negative image of the conductors 36 using a conventional exposure and developing technique. A blanket metal thin film is formed over the substrate and the photoresist pattern such as by physical vapor deposition (sputtering), and a photoresist stripping chemistry is then used to remove the photoresist pattern. Metal deposited on the photoresist is lifted off as the underlying photoresist is dissolved, while metal deposited on the base substrate adheres to the base substrate and remains after lift-off. Accordingly, precise lithographically patterned thin film conductors are formed with precise alignment to the base substrate 30 and vias.
FIG. 2 d shows the structure of FIG. 2 c after formation of sacrificial structures 38 on the base substrate 20 and the conductors 36 . The sacrificial structures 38 are used to define areas of the base substrate 30 and conductors 36 that are to be protected during subsequent deposition of a dielectric material, in a manner analogous to the use of the photoresist mask in the lift-off technique for patterning the conductors 36 . The sacrificial structures 38 are preferably formed of a material that will survive subsequent vacuum deposition of dielectric and that is easily removed in later processing by a etchant that is highly selective of the sacrificial material with respect to other exposed materials. In the preferred embodiment, the sacrificial structures 38 are formed of aluminum that is deposited by a shadow mask process. In the shadow mask process, a shadow mask bearing a positive image of the sacrificial structures is placed in contact with or near the surface of the base substrate 30 and conductors 36 . Aluminum is blanket deposited over the shadow mask such as by a vacuum deposition process such as sputtering, and forms on the substrate in those areas that are exposed by apertures in the shadow mask. After deposition the shadow mask is removed, leaving patterned aluminum structures 38 as shown in FIG. 2 d . In the preferred embodiment it is preferable to form the sacrificial structures 38 to be substantially thicker than the subsequent dielectric layers that is to be patterned using the sacrificial structures 38 .
FIG. 2 e shows the structure of FIG. 2 d after vacuum deposition of a dielectric thin film 40 over the base substrate, the conductors and the sacrificial structures. In the preferred embodiment the dielectric material is alumina and is vacuum deposited by a method such as sputtering or evaporation, producing a highly hermetic dielectric material in an “as fired” form, that is, in a form that will not undergo significant structural changes such as shrinkage during subsequent processing. To enhance the density, adhesion and hermeticity of the dielectric thin film 40 , ion beam assisted deposition (IBAD) may be employed, wherein the deposited dielectric material is bombarded with low energy ions during deposition to provide improved adhesion and coating density. Formation of dielectric thin films by vacuum deposition can produce layers having thicknesses in the range of 100 angstroms to 20 microns (0.00004–0.0008 inches), compared to the conventional minimum green sheet thickness of 0.006 inches or approximately 150 microns. Accordingly, the use of vacuum deposited dielectric thin films rather than conventional sheet dielectrics allows the production of significantly thinner multilayer substrates or the production of multilayer substrates having significantly more layers than those formed by conventional lamination methods. In addition, vacuum deposited layers are highly hermetic and provide significant protection of underlying materials against the outside environment.
FIG. 2 f shows the structure of FIG. 2 e after patterning of the deposited dielectric layer 40 by selective removal of the aluminum sacrificial structures. The aluminum sacrificial structures may be removed selectively with respect to the titanium conductors, alumina base substrate and gold vias using a ferric chloride solution or another mild etchant that is selective with respect to the aluminum sacrificial structures. The etchant reaches the aluminum sacrificial structures through pin-holes and other imperfections in the extremely thin layers of dielectric material that are deposited on the sidewalls of the sacrificial structures. By forming the sacrificial structures to be substantially taller than the dielectric layer, it is ensured that there will be sufficiently thin sidewall coverage and sufficient sidewall surface area to enable penetration of the etchant. As the aluminum sacrificial structures dissolve, the dielectric thin film overlying the sacrificial structures collapses and is rinsed away in subsequent cleaning, leaving a patterned dielectric thin film as shown in FIG. 2 f that protects the majority of the conductors 36 and base substrate 30 surface area while selectively exposing portions of the conductors 36 for connection to overlying conductors. Because the sacrificial structures 38 are precisely positioned relative to the base substrate 30 and conductors 36 using the shadow mask process described above, and because the deposited dielectric thin film 40 will not undergo significant structural changes during further processing, the openings in the deposited dielectric thin film 40 are precisely aligned with the underlying conductors 36 and base substrate 30 , enabling greater via and conductor densities and providing greater process yield.
FIG. 2 g shows the structure of FIG. 2 f after formation of additional welding pads 42 on the top surface of the base substrate 30 , followed by formation of sensor electrodes 44 on the bottom surface of the base substrate 30 . The sensor electrodes 44 are preferably formed of successive thin films of titanium, platinum and titanium that are patterned on the bottom surface of the base substrate 30 by a photoresist lift-off process.
FIG. 2 h shows the structure of FIG. 2 g after formation of caps 46 over portions of the sensor electrodes 44 that are in contact with vias 32 that extend through the dielectric base substrate 30 . The caps 46 prevent access of fluid contaminants to the vias 32 and portions of the base substrate 30 in the vicinities of the vias that may be somewhat amorphous as a result of laser drilling and therefore more susceptible to chemical degradation. In the preferred embodiment the caps 46 are highly pure alumina caps that are formed using a positive shadow mask process, thus allowing precise registration of the caps 46 to the vias 32 .
FIG. 2 i shows the structure of FIG. 2 h after formation of gold contact pads 48 on exposed portions of the conductors 36 . The gold contact pads 48 provide contact points for electrical connection of integrated circuits and discrete devices to the conductors 36 . A gold ring 50 is also formed at the perimeter of the deposited dielectric thin film 40 and defines an area within which circuit components will be mounted. The gold ring 50 is used in later processing for bonding a protective cap over the circuit components. The gold contact pads 48 and gold ring 50 are preferably formed by a photoresist lift-off process.
FIG. 2 j shows the structure of FIG. 2 i after mounting of an integrated circuit 52 and a discrete capacitor 54 to the multilayer substrate composed of the base substrate 30 , the conductors 36 and the deposited dielectric thin film 40 . The integrated circuit 52 is connected to the gold contact pads 48 by wire bonds. In the preferred embodiment, the integrated circuit is in electrical communication with the sensor electrodes 44 on the bottom of the base substrate 30 through the conductors 36 formed on the top surface of the base substrate 30 and the hermetic vias 32 formed through the base substrate 30 . The integrated circuit 52 makes oxygen and glucosine measurements using readings taken from the sensor electrodes 44 and provides a digital output representing those measurements. While the preferred embodiment connects the integrated circuit 52 using wire bonds, in alternative other connection structures such as flip chip and ball grid array structures may be used.
FIG. 2 k shows the structure of FIG. 2 j after bonding of a protective cap 56 to encase the circuit components. The cap 56 is preferably a gold cap that is bonded to the gold ring formed on the deposited dielectric thin film. In the resulting structure the protective cap 56 provides a hermetic seal against fluids at the top surface of the substrate, while the hermetic vias 32 and their associated caps 46 provide hermetic seals against fluids at the exposed bottom surface where the sensor electrodes 44 are located. The deposited dielectric thin film 40 that lies between the gold cap and the base substrate is also hermetically bonded to the base substrate 30 by virtue of its vacuum deposition, and as a result the circuit components are completely hermetically sealed against the outside environment.
While the processing shown in FIGS. 1 a – 1 h and 2 a – 2 k represents a preferred embodiment for producing a blood glucose monitor, the techniques used in this processing are generally applicable to a wide range of applications in which it is desired to produce thin multilayer substrates with a high degree of alignment precision, relatively little shrinkage, and a potentially high conductor and via density. Accordingly, many specific details of the preferred embodiment may be altered, adapted or eliminated to in accordance with various desired implementations.
In general terms the techniques of the preferred embodiment may be adapted to form multilayer substrates comprised of any desired number of dielectric and conductors layers. The substrate is formed of patterned dielectric and conductive thin films that are deposited on a base substrate. Deposited dielectric layers are preferably patterned using sacrificial structures to form openings in the dielectric layers for vias or for exposing larger contact areas of conductors.
The thin films use in accordance with embodiments of the invention are preferably vacuum deposited. For purposes of this disclosure, the term vacuum deposited refers deposition of a material at a low pressure in a controlled atmosphere. Such techniques include evaporation, sputtering (PVD) and chemical vapor deposition (CVD). Evaporation is preferably used where it is desired to form a relatively thick layer, e.g. 10 microns. However evaporation provides relatively poor adhesion and density. The adhesion and density of evaporated layers may be improved through the use of ion bombardment (ion-assisted evaporation). Sputtering (PVD) is preferred where adhesion is a priority. However the growth rate of layers formed by sputtering is approximately an order of magnitude slower than those formed by evaporation. CVD may be used as needed to form layers of materials that are not easily formed by evaporation or sputtering.
With regard to the base substrate, it is preferred in most embodiments to use a rigid sheet of an as-fired dielectric ceramic material. However, the base substrate may be composed of a wide variety of substrate materials since the deposition processes used to form forming dielectric and conductive thin films are performed at relatively low temperatures, and patterning of those thin films using sacrificial structures utilizes relatively mild etchants. While the preferred embodiment uses a substrate comprising 92–96% purity alumina, high purity berillia and aluminum nitride base substrates may also be used. Other types of dielectric substrates such as polyimide flex board and standard printed circuit board substrates comprised of epoxy resin impregnated glass fiber may also be used. In optical applications, substrates such as glass and sapphire may be used. For radiation hardened applications a gallium arsenide (GaAs) substrate may be used, and may be provided with a thin dielectric protective layer as required. In advanced applications, the substrate may be a semiconductor substrate such as silicon or GaAs that has an application specific integrated circuit (ASIC) formed therein by conventional lithographic techniques. Thin film dielectric and metal layers may then be formed on the semiconductor substrate in the manner of the present invention to protect the ASIC and to form sensor electrodes and metal patterns for connection of discrete components to the ASIC.
With regard to conductors, it is preferred to utilize thin film conductors that are patterned by shadow masking, photoresist lift-off patterning or chemical etching. However in alternative embodiments conductors may be formed by other methods such as screen printing. The thickness of the conductors may be selected in accordance with a type of joining operation that will be performed on the conductor. For example, conductors that will be resistance welded may be formed of a thick layer, while conductors that will be connected by a low power technique such as wire bonding may be formed of a thin film. Further, while the preferred embodiment provides conductors that are designed for wire bonding, in alternative embodiments the conductors may be patterned for use in other integrated circuit connection structures, such as flip chip and ball grid array structures. The types of conductor materials that may be used are not limited by processing conditions as in some conventional lamination methods, and may therefore be chosen in accordance with the particular application. Conductor materials may include metals such as platinum, gold, silver, copper, titanium, tungsten, and aluminum, as well as alloys, conductive compounds such as silicides, or any other conductor that is applicable in a particular implementation. While the conductors of the preferred embodiment are formed of successive layers of different conducting materials, single conducting materials may also be employed.
Embodiments of the invention also provide great freedom of choice with respect to the deposited dielectric material. As a general matter the dielectric layer should be capable of formation by a vacuum deposition technique that provides good adhesion to underlying materials and good process control for producing very thin layers. As a general matter any dielectric material that can be obtained in a substantially pure form may be evaporated and vacuum deposited as a thin film on a substrate. Accordingly, a variety of deposited dielectric materials may be used including alumina, aluminum nitride, silicon oxide, silicon nitride, silicon oxynitride, titanium nitride and the like. Vacuum deposited dielectric thin films provide a number of desirable properties, including highly controllable thickness, high hermeticity, dimensional stability, thermal and chemical stability, and tunable dielectric and thermal conductance properties. For purposes of this disclosure, the term “deposited dielectric” is therefore used not only to describe the processing by which the dielectric is formed, but also the resulting structural features of the deposited dielectric that distinguish it from conventional laminated dielectrics, including its conformality and hermeticity with respect to the materials on which it is formed, its high density and adhesion, and its dimensional, thermal and chemical stability.
Thin film dielectric layers are preferably patterned using sacrificial structures formed by shadow mask deposition. While the preferred embodiment utilized a single dielectric thin film having relatively large patterned openings, in alternative embodiments multiple layers of dielectric thin films may be employed, and the dielectric thin films may have very small patterning features such as vias for connecting conductors in adjacent layers. It is preferable to form the shadow mask apertures for small patterning features using laser drilling methods, thereby enabling the formation of vias with diameters as small as 0.002 inches and with spacings as small as 0.006 inches.
Accordingly, using conductive and dielectric thin films and patterning techniques in accordance with embodiments of the invention, the dimensions of multilayer substrate features may be significantly reduced compared to those produced through conventional lamination techniques. The following table compares the minimum dimensions and other characteristic features achievable through conventional lamination techniques and through embodiments of the present invention:
TABLE 1
Conventional
Lamination
Preferred Embodiment
Minimum line width
0.005 inches
0.001 inches
Minimum dielectric thickness
0.006 inches
0.00004 inches
Minimum via diameter
0.005 inches
0.002 inches
Minimum via spacing
0.015 inches
0.006 inches
Shrinkage
in excess of 10%
none
While the multilayer substrate of the preferred embodiment is comprised solely of vias, conductors and dielectric layers, alternative embodiments may integrate or embed passive components such as capacitors, resistors and inductors into the multilayer substrate. For example, while the circuit of the preferred embodiment comprises a discrete capacitor, in alternative embodiments a capacitor may be integrally formed in the multilayer substrate from conductors separated by a deposited dielectric layer. Capacitors may be formed, for example, using a silicon oxide or silicon nitride dielectric layer between conductive plates. Interdigitated capacitors and trench may also be formed. The degree of material control and geometrical precision provided by vacuum deposition and patterning of the dielectric layers allows for precise patterning of the capacitor structure as well as tuning of the capacitor parameters through control of the thickness and dielectric constant of the deposited dielectric layer. Thin film inductors and thin film resistors may also be integrated into the multilayer substrate. Thin film resistors may be patterned from layers of materials such as tantalum nitride (TaN), polysilicon, titanium, cermet or nichrome. In other embodiments, substrate layers may be patterned to form micro-electro-mechanical systems (MEMS) that are integrated with the layers of the substrate. For example, the patterning techniques described above can be used to fabricate structures such as microfluidic structures, valves, reaction chambers, strain gages, micro-actuators, electro-mechanical sensors arrays and optical detectors. Additional properties of the multilayer substrate such as thermal management, power management, shielding and grounding can be precisely controlled through choices of layout and materials.
A wide variety of embodiments may therefore be implemented in accordance with the invention. In general terms, multilayer circuit substrates fabricated in accordance with embodiments of the invention are characterized by a dielectric base substrate having conductors formed thereon, and at least one layer of a patterned vacuum deposited dielectric thin film overlying the conductors. In various implementations, multiple layers of conductors and dielectric thin films may be used, conductors may be formed from thin films, multiple layers may be formed on both sides of the base substrate, and the base substrate may include hermetic vias. It is preferred that the deposited dielectric thin films are patterned using sacrificial structures formed by shadow mask deposition.
FIG. 3 shows a process flow for producing a multilayer circuit substrate that encompasses the preferred embodiment, the aforementioned alternative embodiments, and further alternatives. Initially a dielectric base substrate is provided ( 60 ). Conductors are then formed on the base substrate ( 62 ), preferably by patterning of a blanket layer of a conductive thin film deposited by a vacuum deposition method. Sacrificial structures are then formed on the base substrate and conductors ( 64 ). The sacrificial structures define areas of the base substrate and conductors that are to be protected during subsequent dielectric deposition. The sacrificial structures are preferably formed by shadow mask deposition. A dielectric thin film is then vacuum deposited on the base substrate, the conductors and the sacrificial structures ( 66 ), and the sacrificial structures are removed ( 68 ) to leave a patterned dielectric thin film on the conductors and the base substrate. Further processing such as forming additional conductor layers and dielectric layers or mounting of electronic components may be performed.
It will be apparent to those having ordinary skill in the art that the tasks described in the above processes are not necessarily exclusive of other tasks, but rather that further tasks may be incorporated into the above processes in accordance with the particular structures to be formed. For example, intermediate processing tasks such as formation and removal of passivation layers or protective layers between processing tasks, formation and removal of photoresist masks and other masking layers, application and removal of antireflective layers, doping, cleaning, planarization, annealing and other tasks, may be performed along with the tasks specifically described above. Further, the processes may be performed selectively on sections of a base substrate or at multiple locations on the base substrate simultaneously. Thus, while the embodiments illustrated in the figures and described above are presently preferred, it should be understood that these embodiments are offered by way of example only. The invention is not limited to a particular embodiment, but extends to various modifications, combinations, and permutations encompassed by the appended claims and their equivalents. | A multilayer circuit substrate for multi-chip modules or hybrid circuits includes a dielectric base substrate, conductors formed on the base substrate and a vacuum deposited dielectric thin film formed over the conductors and the base substrate. The vacuum deposited dielectric thin film is patterned using sacrificial structures formed by shadow mask techniques. Substrates formed in this manner enable significant increases in interconnect density and significant reduction of over-all substrate thickness. | 7 |
This invention relates to a synthetic pigment having the color of natural uncalcined umber and to the use of this pigment.
BACKGROUND OF THE INVENTION
Natural umbers differ widely in their composition, depending on origin, and consist of a mixture of various minerals, such as goethite, manganese dioxide, alumosilicates and crystalline quartz. They contain inter alia approximately 40% Fe 2 O 3 , 5 to 10% Mn 2 O 3 and 10 to 20% SiO 2 .
It is known that naturally occurring pigments show distinct variations in composition and color which are troublesome in many applications. In addition, the presence of crystalline quartz in quantities of more than 1.0% is objectionable on account of the carcinogenic effect of corresponding fine dusts. The MAC value for dusts such as these is 0.15 mg solids per m 3 air. In addition, under the Californian Safe Drinking Water and Toxic Enforcement Act, 1985 (Proposition 65), goods containing more than 0.1% crystalline quartz have to be declared.
For the reasons stated above, many naturally occurring pigments have already been displaced from their applications by synthetic pigments because synthetic pigments are not attended by the disadvantages mentioned.
Natural umbers are used inter alia in paints and lacquers, for example in emulsion paints and multipurpose tinting pastes. The umbers are often used in admixture with other pigments in various quantitative ratios, for example for "breaking" colors. For the applications mentioned, it is very important that a synthetic pigment such as this should correspond to natural umber in color in various mixing ratios (lightening) of pigment and white pigment. There has been no shortage of attempts to adjust a corresponding pigment by mixing commercially available pigments, more particularly by mixing iron oxides. However, corresponding mixtures, such as commercial iron oxide brown pigments for example, undergo an unwanted change of shade with increasing lightening.
Accordingly, the problem addressed by the present invention was to provide a synthetic pigment having the color of natural uncalcined umber which would not have any of the described disadvantages.
BRIEF DESCRIPTION OF THE INVENTION
Pigments which satisfy these requirements have now surprisingly been found. They have the color of natural uncalcined umber and are characterized by an iron content, expressed as Fe 2 O 3 of more than 85% by weight and a content of crystalline silica of less than 0.1% by weight. The pigments according to the invention can be obtained by mixing iron oxides of spinel structure and/or hematite structure and, optionally, an iron oxide yellow.
DETAILED DESCRIPTION
Accordingly, the pigment according to the invention preferably consists of a mixture of synthetic magnetite black (Fe 3 O 4 ), at least one synthetic maghemite brown (γ-Fe 2 O 3 ) or hematite red (β-Fe 2 O 3 ) and, optionally, synthetic goethite yellow (γ-FeOOH) and/or lepidocrocite orange (γ-FeOOH).
The preparation of the starting materials is generally known, cf. for example Ullmann, Enzyklopadie der technischen Chemie, 4th Edition, Weinheim (1979), Vol. 18, pages 600-604. A preferred process for the production of maghemite is described in DE-A 3 820 499.
In one preferred embodiment, the pigment according to the invention contains magnetite black in quantities of 10 to 80% by weight, hematite red in quantities of 0 to 60% by weight, maghemite brown in quantities of 0 to 30% by weight, goethite yellow in quantities of 1 to 40% by weight and lepidocrocite orange in quantities of 1 to 10% by weight as key constituents of the mixture.
In one particularly preferred embodiment, the mixture contains 50 to 75% by weight magnetite black, 1 to 40% by weight goethite yellow, 0 to 10% by weight hematite red and 0 to 30% by weight maghemite brown.
In addition, the low content of soluble salts in the pigment according to the invention is an advantage. According to DIN ISO 787/Part 8, it is less than 1.0% and preferably from 0.5 to 0.9%. The content of soluble salts in natural umbers, at up to 1.5%, is distinctly higher and is therefore a disadvantage for certain applications.
The pigment according to the invention preferably has an iron content, expressed as Fe 2 O 3 , of 85 to 99% and a manganese content of less than 1%. The crystalline quartz content was determined by diffractometry after repeated evaporation with hydrochloric acid and after calcination to hematite at 800° C. and is less than 0.1%. Accordingly, the low crystalline quartz content and the low manganese content are particularly advantageous because, in contrast to natural umber, no elaborate measures for avoiding dust emission have to be taken for the pigment according to the invention.
The pigment mixtures may be obtained in the usual way by mixing the various components and grinding the mixture in a dismembrator or in a vibrating disk mill. To determine the color tones, the pigments are colorimetrically evaluated both in pure form and after lightening in various ratios in Alkydal® F48 or L64 (alkyd resins, products of Bayer AG) in accordance with DIN 6174 (equivalent to ISO DIN 7724, 1-3 Drafts). Various quantities of pigments and TiO 2 R-KB-2® (a product of Bayer AG) were used to prepare the lightened forms. The color values are expressed in CIELAB units either as absolute values or in relation to a commercially available uncalcined umber.
The color of the pigments according to the invention is characterized in that the color angle h both for the pure form and for the form lightened with TiO 2 in a ratio of 1:10 may assume values of 60 to 90, the saturation C* being from 1 to 20 and preferably from 2 to 12. Accordingly, these pigments are clearly distinguished from known iron oxide pigments. To evaluate lightening behavior, the residual color differences between the pigments according to the invention and commercial umbers lightened in various ratios were determined. The pigment according to the invention shows very little difference in color from natural umbers both in pure form and in the lightened forms.
Commercially available iron oxide black pigments in the form of magnetite, red pigments in the form of hematite, yellow pigments in the form of goethite and/or lepidocrocite and a brown pigment in the form of maghemite (γ-Fe 2 O 3 ) were used for the mixtures. Pigments showing neutral lightening behavior corresponding to natural umber were mainly obtained in the case of mixtures containing an iron oxide black as principal component and an iron oxide brown in the form of maghemite, an iron oxide red in the form of hematite and an iron oxide yellow in the form of goethite as secondary components.
The pigments according to the invention are strongly colored and show coloring strengths of 100 to 160% compared with natural umbers. The specific surface of the pigments according to the invention, as measured by the BET method, is from 10 to 30 and preferably from 15 to 20 m 2 /g (DIN 66 131, nitrogen one-point method).
The pigments according to the invention are readily dispersible in binders of the type used for the production of multipurpose tinting pastes. The lower binder demand compared with natural umbers and the high solids content of the pastes obtained are particular advantages.
The present invention also relates to the use of the pigment according to the invention for the production of paints and lacquers, such as complete paints and tinting paints, to its use in multipurpose tinting pastes and to its use for pigmenting building materials.
The following Examples are intended to illustrate the invention without limiting it in any way.
COMPARISON EXAMPLES
The properties of commercial, natural, uncalcined umbers are investigated in Comparison Examples C1 to 4. The results of these investigations are set out in Tables 1.1, 1.2 and 1.3.
TABLE 1.1______________________________________Contents and physical data of natural uncalcined umbers Comparison Examples 1 2 3 4______________________________________% Fe.sub.2 O.sub.3 40.0 47.6 47.4 --% Mn.sub.2 O.sub.3 6.9 9.5 6.6 --% SiO.sub.2 21.4 13.3 20.8 --% Al.sub.2 O.sub.3 3.3 -- 3.5 3.6% Quartz, crystalline 1.3 0.4 -- 0.9Spec. surface, m.sup.2 /g 64 -- 82 103Oil number, g/100 g 53 -- -- 40______________________________________ -- = not determined
TABLE 1.2______________________________________Color values of the natural umbers of Comparison Example1 lightened in various ratiosLighteningpigment: TiO.sub.2 L* a* b* C* h______________________________________Pure form 26.5 0.6 1.7 1.8 70.61:1 50.5 1.0 5.4 5.5 80.11:2 50.5 0.9 5.4 5.4 80.1 1:3.33 58.1 0.6 4.0 4.0 81.51:5 63.0 0.5 3.7 3.7 82.31:7 66.9 0.4 3.3 3.3 83.1 1:15 74.2 0.4 2.9 3.0 82.3 1:30 80.2 0.3 2.3 2.3 81.9______________________________________
TABLE 1.3______________________________________Color values of the natural umbers of Comparison Examples1-4 in pure form and in lightened form (1:10)ComparisonExample L* a* b* C* h______________________________________C1 Pure form 26.5 0.6 1.7 1.8 70.6C2 Pure form 28.0 1.7 3.5 3.5 64.6C3 Pure form 26.6 0.3 2.3 2.3 82.4C4 Pure form 26.5 1.0 2.6 2.8 69.0C1 Lightened 70.7 0.4 3.0 3.9 82.4C2 Lightened 72.0 2.0 11.1 11.3 80.0C3 Lightened 71.7 0.7 4.2 4.3 80.5C4 Lightened 70.8 1.7 4.8 5.1 70.5______________________________________
EXAMPLES
For the Examples, various commercial pigments were mixed with one another. Maghemite brown, as described in DE-A 3 820 499, was also used for some mixtures.
To prepare the mixtures, the components were combined, homogenized and ground in a dismembrator or in a vibrating disk mill. The compositions of the mixtures are shown in Table 2.1.
Bayferrox 318 is a synthetic magnetite black (Fe 3 O 4 ). Bayferrox 930 and 415 are synthetic goethite yellows (α-FeOOH). Bayferrox 110 is a synthetic hematite red (α-Fe 2 O 3 ). Bayferrox 943 is a synthetic lepidocrocite orange (γ-FeOOH).
TABLE 2.1______________________________________Composition of the mixtures of Examples 1-10Mixture components in % by weight Bayferrox ®*Example 318 930 415 110 943 Maghemite brown______________________________________1 70 4 -- -- 262 70 -- 4 -- -- 263 59 -- 10 -- -- 404 40 -- 20 10 -- 305 50 -- 30 10 -- 106 40 -- -- 20 -- 407 10 -- 10 20 -- 608 55 -- 40 5 -- --9 58 -- 37.5 4.5 -- --10 60 -- 30 5 5 --______________________________________ *a product of Bayer AG
TABLE 2.2______________________________________Color values of Examples 1-10, pure formExample L* a* b* C* h______________________________________1 27.5 0.6 2.8 2.9 77.92 27.2 0.9 3.5 3.6 76.63 30.0 2.4 6.6 7.0 70.04 30.0 1.9 6.2 6.5 73.05 28.8 0.6 4.1 4.1 81.76 28.7 2.1 4.9 5.3 66.87 32.2 5.0 9.8 11.0 63.08 32.9 1.8 10.1 10.3 79.99 29.5 1.1 5.6 5.7 78.910 29.2 1.1 5.5 5.6 78.7______________________________________
TABLE 2.3______________________________________Color values of Examples 1-10 in lightened form (1:10)Example L* a* b* C* h______________________________________1 67.3 0.8 3.3 3.4 76.42 68.6 1.3 3.2 3.5 67.93 70.4 2.9 7.1 7.7 67.84 70.1 2.4 6.9 7.3 70.85 70.3 0.8 4.2 4.3 79.26 67.3 2.9 5.6 6.3 62.67 69.1 5.4 11.3 12.5 64.68 74.0 1.3 7.7 7.8 80.49 71.3 1.0 3.7 3.8 74.910 71.8 1.1 3.5 3.7 78.7______________________________________
TABLE 2.4______________________________________Color values of Example 1 for various lightening ratiosLighten-ing ratio L* a* b* C* h______________________________________Pure form 27.5 0.6 2.8 2.9 77.91:2 47.2 1.0 2.4 2.6 68.31:5 58.7 0.9 3.3 3.4 74.71:7 62.6 0.8 3.2 3.3 76.0 1:15 70.2 0.7 3.0 3.1 77.0 1:30 76.8 0.6 2.8 2.9 77.7______________________________________
TABLE 2.5______________________________________Color values of Example 9 for various lightening ratiosLighten-ing ratio L* a* b* C* h______________________________________Pure form 29.5 1.1 5.6 5.7 78.91:10 71.3 1.0 3.7 3.8 74.91:20 77.7 1.0 3.2 3.4 72.61:30 80.9 1.0 2.9 3.1 71.0______________________________________
TABLE 2.6______________________________________Color differences of certain pigment mixtures of Examples1-10 lightened in a ratio of 1:10 in relation to thenatural umber of Comparison Example 1 ColoringExample strength (%) Δa* Δb* ΔC*______________________________________1 151 0.3 0.1 0.12 154 0.5 -0.9 -0.69 107 0.1 0.2 0.2______________________________________
TABLE 2.7______________________________________Color differences of the pigments mixtures of Examples 1and 2 in relation to the natural umber of ComparisonExample 1 for various lightening ratios (experimentallightness match)Lighten-ing ratio ΔL* Δa* Δb* ΔC*______________________________________Example 11:3 0.0 0.4 -1.1 -0.91:5 0.0 0.5 -0.6 -0.41:10 0.0 0.4 0.9 0.11:15 0.0 0.4 -0.2 -0.11:20 0.0 0.4 0.2 0.31:30 0.0 0.3 0.3 0.4Example 2Pure form 0.8 0.1 1.1 1.11:5 0.0 0.3 0.1 0.21:10 0.0 0.3 0.2 0.31:20 0.0 0.2 0.5 0.351:30 0.0 0.2 0.4 0.4______________________________________
TABLE 2.8______________________________________Contents of the mixtures of Examples 1-10 % Cryst. % Water-Example % Fe.sub.2 O.sub.3 % Mn quartz soluble salts______________________________________1 94 <0.1 0.82 94 0.5 <0.1 0.93 93 <0.1 --4 92 <0.1 --5 91 <0.1 --6 95 <0.1 --7 94 <0.1 --8 89 <0.1 0.59 90 <0.1 0.410 90 <0.1 --______________________________________ -- = not determined
TABLE 2.9______________________________________Other characteristic data of the mixtures of Example 1- 10 S.sub.BET Oil numberExample m.sup.2 /g g/100 g______________________________________1 14 162 14 153 15 234 15 255 14 256 14 257 19 288 14 269 14 2610 -- 26______________________________________
EXAMPLE 1
The pigment mixture of Example 1 both in pure form and in lightened form shows minor differences in color from the pigment of Comparison Example 1 (see Tables 1.2 and 2.4) and, with a coloring strength of 151%, is dinstinctly stronger in color. The pigment mixture contains less than 0.1% crystalline quartz and 0.8% water-soluble salts. The oil number and the specific surface, at 16 g/100 g and 14 m 2 /g, respectively, are distinctly lower than in the natural uncalcined umbers.
EXAMPLE 2
The pigment mixture corresponds in its properties to Example 1, but contains a smaller amount of soluble salts.
EXAMPLES 3-7
The pigment mixtures of Examples 3-9 both in pure form and lightened in a ratio of 1:10 show a relatively high yellow component and thus correspond to the natural uncalcined umbers with an increased yellow tinge as represented, for example, by Comparison Example 2.
EXAMPLES 8-10
The pigments of these Examples correspond coloristically to the natural umber of Comparison Example 1. The coloring strength is approximately 107%. | Pigments having the color of natural uncalcined umber contain more than 85% by weight of iron oxides, expressed as Fe 2 O 3 , and less than 0.1% by weight of crystalline silica are obtained by mixing iron oxides of spinel structure and/or hematite structure with or without iron oxide yellow and said pigments are useful in coloring paints, lacquers and building materials. | 2 |
SUMMARY OF THE INVENTION
Energy cycles of the type which utilize steam turbines to drive electrical generators are conventionally low in energy output and thermal efficiency.
The straight condensing cycle type in which all of the effluent steam from the turbine is put through waste heat condensation to provide boiler feed water has a heat rate of 12,700 Btu/Kw-Hr and a 27% efficiency.
When the Rankine steam cycle is employed, a major part of the effluent steam from the turbine is used to pre-heat feed water for the steam generator, thereby reducing waste heat and providing a heat rate of about 10,100 Btu/Kw-Hr and a thermal efficiency of about 34%. This operation still entails a heat loss due to change of state of 970-1,000 Btu/lb of steam.
According to the subject invention, up to half or more of the extraction steam from the turbine is passed through a Repressor/Reheater cycle, or a repressurization and reheating cycle, and back to the turbine for conversion to mechanical energy. The heat rate of the Repressor/Reheater cycle in conjunction with the steam turbine is about 4,500 Btu/Kw-Hr and the thermal efficiency is about 74%.
The essential object of the invention is to combine the Repressor/Reheater cycle with a regenerative cycle, such as the Rankine cycle.
When the steam flows from the turbine are regulated to provide a 20% flow to the Repressor/Reheater cycle and an 80% flow to the Rankine cycle, the heat rate and efficiency figures are about 8,200 Btu/Kw-Hr and 39%. With a 50% steam flow to the Repressor/Reheater phase and a 50% flow to the Rankine phase, the heat rate and efficiency figures are about 6,000 Btu/Kw-hr and 54%. With an 80% steam flow to the Repressor/Reheater phase and a 20% steam flow to the Rankine phase, the heat rate and efficiency values are about 5,000 Btu/Kw-hr and 65%.
The repressor is adapted to convey compartmented charges of partially expanded steam from the turbine into and through stages of supply of higher pressure steam from the turbine. Steam in the highest pressure stage of the repressor is displaced through a fired reheater in which the enthalpy of the steam is increased substantially to permit its readmission into the reentry steam turbine to generate additional energy at higher output.
The repressor is constructed along the lines of the toroidal pump shown and described in my U.S. Pat. No. 3,930,757, issued Jan. 6, 1976, although it is driven by an electro-magnetic drive energized by regulated frequency electric polyphase power as shown and described in my U.S. Pat. No. 4,593,215, issued Jun. 3, 1986.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a semi-schematic view of the straight condensing cycle system of the prior art.
FIG. 2 is a semi-schematic view of the regenerative Rankine cycle system of the prior art.
FIG. 3 is a semi-schematic view of a preferred system of the invention.
FIG. 4 is a view in edge elevation of the repressor unit.
FIG. 5 is a plan view of the repressor with breakaway portions to illustrate mechanical and electrical construction.
FIG. 6 is an enlarged view of the repressor portion shown in the right-hand breakaway part of FIG. 5.
FIG. 7 is an enlarged transverse view of the torus or ring of the repressor, as along lines 7--7 of FIG. 5.
FIG. 8 is a semi-schematic view showing in developed relation stator and rotor winding, pole and core elements.
FIG. 9 shows a data table relating to thermal energy cycle comparison.
FIG. 10 shows a data table relating to combined Rankine and Repressor/Reheater cycles.
PRIOR ART
The straight condensing cycle of FIG. 1 comprises steam turbine 10, electrical generator 12 in driven relation to turbine 10, condensor 14 to condense the effluent steam from turbine 10 to water, conduit 16 with pumps 18 to feed the resulting water to boiler 20, heater 22 containing fuel burners, not shown, and steam line 24 extending from the boiler 20 through the heater 22 to the turbine 10.
As indicated in the table of FIG. 9, the straight condensing cycle has a heat rate of 12,700 Btu/Kw-hr and a 27% efficiency.
In FIG. 2, which depicts the regenerative or Rankine cycle, elements corresponding to those of FIG. 1 have similar reference numbers. This cycle includes a plurality of heat exchangers 26 in the conduit 16 and a plurality of effluent steam conduits 28 interconnecting the turbine 10 and the exchangers 26 and adapted to deliver effluent steam at varying temperature-pressure values to the exchangers to pre-heat the returned feed water to the boiler. Only part of the effluent steam is condensed in condensor 14, the remainder being used to pre-heat the feed water.
As indicated in the table of FIG. 9, the Rankine cycle of FIG. 2 has a heat rate of 10,100 Btu/Kw-hr and a 34% efficiency.
DESCRIPTION OF THE INVENTION
FIG. 3 shows a preferred embodiment of the apparatus of the invention, a combination of the conventional cycle of FIG. 2 and a Repressor/Reheater cycle indicated generally by 30 and 32.
As indicated in the tables of FIGS. 9-10, the Repressor/Reheater cycle of FIG. 3 has a heat rate of 4,600 Btu/Kw-hr and an efficiency of 74%. When this cycle is combined with the Rankine cycle of FIG. 2, the overall heat rate and efficiency values are increased substantially. When 20% of the effluent steam goes to the Repressor/Reheater part of the equipment and 80% to the Rankine part, the overall heat rate is 8,200 Btu/Kw-hr and the overall efficiency is 39%; when the effluent steam is apportioned 50%-50%, the heat rate is 6,000 Btu/Kw-hr and the efficiency is 54%; and when the effluent steam is apportioned 80% to the Repressor/Reheater part and 20% to the Rankine part, the heat rate is 5,000 Btu/Kw-hr and the efficiency is 65%.
The repressor 30 comprises (See FIGS. 4-5) a toroidal casing 34, preferably mounted horizontally. The casing has upper and lower portions 36, 38 provided with matching flanges 40 and 42. The flanges are secured together to a leak-proof tightness by studs 44 and nuts 46. Some of the studs 44 are threadably driven into threaded sections of metal support saddles 48. The saddles are integral with base plates 50 which are firmly secured as by studs 52 and nuts 54 to suitable concrete footings, not shown. So mounted, the casing 34 and its internal conveyor ring 56 are anchored against stresses from connecting pipes and to suppress vibration of casing 34 and ring 56.
The internal conveyor ring 56 is comprised of a full circular complement of equally spaced apart seal discs 58 connected at their centers by arcuate connector/spacer rods 60. Discs 58 are machined to provide rectangular grooves 62 (see FIG. 6) into which piston rings 64 are fitted. Rings 64 have sufficient lateral clearance in grooves 62 to enable the rings to self-expand diametrically to fit against casing bore surface 66 for continuously maintaining containment of steam and the pressure thereof within the intra-disc compartments 68.
Two sets of steam conduits interconnect turbine 110 and repressor 30. One set comprises conduits 70, 72, 74, 76, 78 adapted to convey extraction steam from turbine 110 into pre-selected intra-disc compartments 68.
Conduits 72, 74, 76, 78 are connected to the lower casing portion 38 through ports 80 which are flush with the casing bore 66. Conduit 70 connects to the upper casing portion 36 through conduit 70A terminating in port 82 and conduit 70B terminating in port 83. Conduit 70A serves to convey the highest pressure steam to chambers 68 for their final pressurization and conduit 70B serves to convey the highest pressure steam to the chambers 68 at a later point in their rotative positional sequence to force the high pressure steam out of the chambers 68 and into conduit 84 to the reheater 32.
Ports 80 and 83 are angled forwardly in the direction of rotation of ring 56 so that little or no energy is required to drive the ring other than that furnished by the steam passing through these ports. Port 83 is provided with a slightly constricted jet nozzle outlet having an angle alpha between the axis of said outlet and the axis of casing bore 66. The angle alpha may have a value of from about 30° to about 45° and is shown as having a value of 38°.
The second set of steam conduits interconnecting turbine 110 and repressor 30 comprises conduit 84, which extends between repressor 30 and reheater 32 and between reheater 32 and turbine 110, and conduits 86, 88, 90, 92 extending between the repressor and the turbine. The conduits 84, 86, 88, 90, 92 convey injection steam to the turbine. Conduit 94 vents the steam-depleted chambers 68 or the repressor to the exhaust steam manifold 96 of the turbine. Conduits 84-94 connect to the lower casing portion. Conduits 70B and 84 are in general alignment with each other and are generally similarly angled relative to the path of rotation of ring 156.
The steam pressures within the mixed-pressure turbine at the outlet ends of conduits 84, 86, 88, 90, 92 are substantially lower than the steam pressures in the repressor at the inlet ends of said conduits, thereby producing the required steam flow from repressor to turbine. The steam pressures within the repressor at the outlet ends of conduits 70, 72, 74, 76, 78 are substantially lower than the steam pressures in the turbine at the inlet ends of said conduits, thereby producing the required steam flow from turbine to repressor.
Repressor 30 does not act as a pump. Within each transport ring compartment the steam pressures on the leading and trailing discs 58 are the same. Repressor 30 acts as a conveyor to move compartments of progressively higher steam pressure between the inlets of conduits 78 and 70 and to move compartments of progressively lower steam pressure between the inlets of conduits 84 and 92.
In the progressive nature of charging the repressor with live extraction steam from the turbine, the extraction steam has already delivered kinetic energy to the turbine blades. It will now be repressurized through the repressor, reheated through the reheater, and delivered to the turbine to impart considerably more kinetic energy thereto without going through the thermodynamically wasteful change of state to water in a condensor, as occurs with the turbine exhaust steam in condensor 114.
By eliminating a substantial portion of the waste energy of the FIG. 2 steam system chargeable to the latent heat losses of the steam, the combined steam of the invention embodiment of FIG. 3 is rendered substantially more energy-efficient inasmuch as the efficiency of the Repressor/Reheater steam cycle approaches 80%.
The essential purpose and function of the Repressor/Reheater sub-system is therefore seen to be the conveying of compartmented charges of partially expanded steam into and through stages of supply of higher pressure steam to a fired reheater where the enthalpy of the steam is increased substantially to permit its readmission into a reentry steam turbine to generate additional energy at higher output.
For operation of the repressor at low speed and for rotational speed control of the rotor or ring 156 thereof, an electro-magnetic drive mechanism is provided. The purposes, function, constructional arrangement, and manner of operation are described in full detail in my U.S. Pat. No. 4,593,215, issued Jun. 3, 1986.
The electro-motive drive mechanism is essentially a pair of side-by-side conventional polyphase induction motors. The armature windings 130 are installed in an arcuate recessed housing portion 132 of the lower portion 38 of the repressor casing and firmly fastened in position. In the peripheral sense, the windings 130 and their magnetic cores 133 extend only as a partial semicircle. The electro-magnetic rotor 134 is fabricated as a side-by-side pair of rings 136 inset into the repressor rotor or ring 156 and firmly attached thereto in registry with the stationary armature electro-magnetic circuitry comprising windings 130 and magnetic cores 133. Interjacent recesses 138 in the armature housing 132 and repressor rotor 156 are filled with high temperature particulate iron/epoxy platic 140 which laterally encloses and anchors windings 130, cores 133 and rings 136 in place. Polyphase electric current is led into the armature section by electrically insulated leads 142.
As shown in FIG. 8, and in more detail in U.S. Pat. No. 4,593,215, the disposition of the armature windings 130 provides for opposed magnetic polarities to provide opposed induced rotor currents which serve to oppose the setting up in the discs 58 of undesirable stray heating currents.
FIG. 3 sets forth exemplary operating temperature and/or pressure conditions for the steam entering and leaving turbine 110.
In the conventional or Rankine cycle portion of FIG. 3 elements corresponding to those shown in FIGS. 1-2 are identified by corresponding reference numerals plus 100.
Main steam at 1,000# or p.s.i. and 900° F. is sent to turbine 110 through line 124. Exhaust steam from the turbine is condensed in condensor 114. The condensate passes into line 116, is pumped through heat exchangers 126 where it is heated to 445° F., and is then pumped into boiler 120. Steam from the boiler passes through line 124 and superheater 122 and to the turbine.
Extraction steam from the turbine passes through lines 128 to the heat exchangers 126 at 400#-445° F., 280#-411° F., 150#-358° F., and 20#-228° F., as indicated in FIG. 3.
Extraction steam at 750# for line or conduit 70, at 400# for line 72, at 280# for line 74, at 150# for line 76, and at 20# for line 78, is sent to the repressor 30 from turbine 110.
Injection steam at 675# for line 84, at 350# for line 86, at 230# for line 88, at 120# for line 90, and at 70# for line 92, is sent to the turbine from repressor 30.
Since the 750# steam of line 70 displaces the steam from the ring compartments 68 into line 84, the initial pressure in line 84 is also 750#. As line 84 passes through superheater 32 and reaches turbine 110, the steam pressure therein has dropped to 675# due to friction losses. | Multi-stage extraction steam is taken at varying pressures from a mixed pressure turbine and sequentially charged into closed path conveyor compartments to progressively increase the pressure of steam within the compartments. The highest pressure stage of extraction steam is then used to displace the steam from the compartments through a reheater and back to an injection station at the turbine, thereby repressurizing and reheating effluent turbine steam and returning it to the turbine for reuse without incurring the heat losses of condensation. | 5 |
PRIORITY CLAIM
[0001] This application claims priority of the U.S. provisional application titled “Method to Measure and Demonstrate Real Size of Objects on Computer Displays and Cell Phone Screens,” filed on Dec. 3, 2008, and with application No. 61,119,714.
BACKGROUND
[0002] Many retailers advertise their merchandise by posting photos and videos on Internet websites. Customers can browse through the sales items on display at those websites from their computers and can purchase whatever they desire over the Internet with a click of a button. More convenient than in store shopping, however, buying over the Internet does have drawbacks. Because a customer can not physically check out a sales item, she is unlikely to appreciate the unique product design or to get a feel of the dimensions of a sales item by looking at photos and videos. A cautious customer may require more persuasion than what photos and videos can proffer. A frustrated customer may return a piece of merchandise purchased over the internet when he realizes it is not of a desired size or it looks quite different in real life than what is shown on the website. Different methods have been used to allow Internet users to get a sense of the true size or other features of the sales item. FIG. 1 a shows an example of such methods.
[0003] In FIG. 1 a , a photo 102 shows an image of a human hand 104 holding a digital camera 108 . By demonstrating that the digital camera 108 can fit into the palm of the human hand 104 , the photo 102 conveys to a viewer how small the digital camera 108 is. Other comparisons, such as using a standing human being, are frequently used as well to convey a rough sense of the real object. Viewers can perceive how large or small the item truly is but will not be able to gauge it precisely because the sizes of human hands or the heights of human beings vary widely. Sometimes a standard reference object, such as a ruler. is photographed together with an object. While a viewer can read the precise measurements of that object by referencing the ruler, such method differs little from labeling the object numerically with its geometric dimensions.
[0004] In-store shopping has the advantage of allowing customers to touch and feel the sales items that are on display. But it also has drawbacks of its own. It is difficult for a customer to find out how a product displayed in a store will fit at home after it has been purchased. For example, before a customer buys a piece of furniture for her home, she may want to make sure that the piece of furniture fits into her home environment. FIG. 1 b illustrates the problem she might face. In FIG. 1 b , a home environment 152 includes a sofa 154 and a chair 160 . The customer wants to purchase a coffee table 158 that will not only fit into the space between the sofa 154 and the chair 160 but also match the existing décor. Normally, the customer can measure and write down the dimensions of the corner space before going to the store. Once she gets there she can compare the measurements of the coffee table 158 with what she has written down. For the rest, she can only rely on her memory to make sure that the color and the style of the coffee table 158 match those of the sofa 154 and chair 160 .
[0005] Innovative methods are needed to allow a customer to enjoy in-store browsing experience while sitting in front of a computer or to bring her home environment with her while shopping in store.
SUMMARY
[0006] In general, methods of displaying an object in an image, a video or a series of images with desired what you see is what you get (WYSIWYG) effects are disclosed. One of the WYSIWYG effects is making the size of the object in the image or the video equals or approximately equals to its real size. With a display system that includes one or more display elements or display units, such method may include the following steps. First, for each geometric dimension, the size of a display element of the display system is derived and the number of display elements that the object in the desired size spans is calculated. Second, for each geometric dimension, based on the number of display elements, the 2-dimensional object in the desired size is presented by uniformly resizing the image, the video or the series of images. The method can be used to display a 2-dimensional object or the 2-dimensional features of a 3-dimensional object. The method can also be used to display multiple objects together with one of the multiple objects fitted in a desired size. These methods may be particularly useful to online retailers because online retailers want to display a piece of sales item in a particular size, for example, its real size, in order to allow an online shopper to appreciate a certain feature of that item, for example, the compact design. For example, the sales item may be a digital camera and displaying the digital camera in its real size allows an online shopper to appreciate how compact the camera design is.
[0007] In one implementation of these methods, the size of each display element of a display system along one particular geometric dimension is derived from dividing the length of the display system by a resolution in that geometric dimension.
[0008] The size of a display element may be also determined through a user calibration process. One type of user calibration process includes the following steps. First, a user is asked to input the diagonal size of the display system. Then the user input is verified by presenting a well known 2-dimensional object in its real size based on the user input of the diagonal size of the system. If the user input is incorrect, the presentation of the well-known object will not match the real object.
[0009] Another type of user calibration process involves a user creating a profile of a well known object on the display system by placing a calibration point on the display system for each of the geometrical points of the well known object. Then a computer application implemented for this type of user calibration process measures the size of the profile and determines the number of display elements filled by the profile for each geometric dimension. The application calculates the size of a display element by dividing the size of the profile by the number of display elements for that geometric dimension.
[0010] Yet another type of user calibration process involves a user placing a well known object on the display system adjacent to a frame of the display system for support and alignment, and marking a first geometric point of the well know object. A computer application implemented for this type of user calibration process generates a reference line on the display system that connects the first geometric point of the well known object and a second geometric point that is diagonally opposite to the first geometric point of the well known object. The application then creates a profile of the well known object on the display system based on the first geometric point, the reference line, and the geometric shape of the frame of the display system. For each geometric dimension the application measures the size of the profile, determines the number of display elements filled by the profile, and calculates the size of a display element by dividing the size of the profile by the number of display elements for that geometric dimension.
[0011] In some implementations, the well known object used in the above user calibration processes may be a driver's license card. When generating a profile of a driver's license card on the display system, a user may align the left side of the driver's license card with an edge of the display system and use the display frame to support the driver's license card. The user then places the cursor on one geometric point that is on either the top side or the right side of the driver's license card by using a mouse or keyboard. The well known object may also be a credit card or a compact disc.
[0012] In some implementations, each display element in a display system is a square and of the same size. In other implementations, each of the display element is a rectangle and of the same size.
[0013] In some implementations, for each geometric dimension, the resolution of the display system may be stored electronically at a pre-specified location. The length of the display system may be derived from the length of a diagonal line of the display system and the length-to-width ratio of the display system. The length of the display system may also be provided by a user.
[0014] In general, to calculate the number of display elements that the object in the desired size spans for each geometric dimension, the desired size of the object is divided by the size of the display element for that geometric dimension. The desired size of the object may be known before hand or be derived from a picture of the real object taken by a camera with known configuration. The known configuration of the camera may include the distance between the object and the lens system of the camera, the focal distance of the lens system of the camera, and distortions caused by the camera. To increase accuracy, distortions may be corrected during the calculation.
[0015] Also disclosed in this specification is a method of displaying on a display system an object in a desired size relative to a background image. The method may include the following steps. For each geometric dimension, first figure out the real size of the object.
[0016] Second derive the desired size of the object relative to the background based on the dimensional information of the background and the true size of the object. And finally calculate the number of display elements that an image of the object spans when the image is in the desired size relative to the background and display the image of the object based on the above calculation. One application of such method may be found in the process of buying a piece of furniture. The background is the home environment in which the piece of furniture will be placed.
[0017] This specification also discusses a method on constructing 3-dimensional features and size measurement information for a target object using one camera. The method includes the following steps: (a) selecting a reference object; (b) taking a picture that contains an image of the reference object and an image of the target object; (c) calibrating the camera using the image of the reference object to determine the rotation matrix and the translation matrix of the camera; (d) constructing the 3-dimensional features and size measurement information for the image of the target object based on the rotation and translation matrices of the camera; and (e) displaying the image of the object with its 3-dimensional features using the constructed 3-dimensional features and measurement information.
[0018] A method of displaying an image of an object with 3-dimensional effects is also disclosed. Such method includes the following steps. First determine an appropriate size of a 2-dimensional feature of the object to be displayed on the display system and calculate the number of display elements that the 2-dimensional feature of the object spans when it is in the appropriate size. Second for each of the 3-dimensional effects in the image derive a resize ratio by dividing the distance between a viewer and the viewing panel of the display system by the distance between the 3-dimensional feature and the viewer. Finally, based on the resize ratio, display the 3-dimensional feature.
[0019] A second method of displaying an image of an object with 3-dimensional effects on a display system includes a different set of steps. First calculate the appropriate size of a front side of the object to be displayed on the display system as if the front side of the object were placed at a location that is of a distance equal to the distance between a viewer and the viewing panel of the display system. Second derive a resizing ratio for the front side by dividing the appropriate size of the front side of the object by the real size of the front side of the object. Third display the image of the object with 3-dimensional effects by adjusting the entire image of the object according to the resizing ratio.
[0020] The system that can be used to implement or run the above disclosed methods may include a display system comprising one or more display elements and a processing unit that can carry out those method steps. A computer-readable medium may be used to store the instructions for carrying out the above disclosed methods.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 a is an advertisement showing a digital camera placed in the palm of a human hand.
[0022] FIG. 1 b illustrates a problem faced by a customer when buying a piece of furniture.
[0023] FIG. 1 c illustrates a 2-dimensional object with WYSIWYG effects on a computer display.
[0024] FIG. 1 d illustrates a 3-dimensional object with WYSIWYG effects on a computer display.
[0025] FIG. 1 e illustrates a disappearing railway with WYSIWYG effects on a computer display.
[0026] FIG. 1 f illustrates a 3-dimensional object in a video frame with WYSIWYG effects on a computer display.
[0027] FIG. 1 g illustrates multiple images of different objects placed together with WYSIWYG effects on a computer display.
[0028] FIG. 2 a is a display system that comprises a number of display elements.
[0029] FIG. 2 b illustrates calibrating a display system based on user input.
[0030] FIG. 2 c illustrates deriving the aspect ratio of a display system based on user input.
[0031] FIG. 2 d illustrates deriving the dimensional information of a display system based on user input.
[0032] FIG. 3 is a display system displaying an iPhone.
[0033] FIG. 4 a is a display system displaying an object in its reality view when its dimensions are known.
[0034] FIG. 4 b is a display system showing a picture of an object in its reality view when the object's dimensions are known.
[0035] FIG. 4 c illustrates a camera configuration.
[0036] FIG. 5 displays an object in its reality view based on the size of the picture and camera configuration.
[0037] FIG. 6 illustrates fitting an image of a coffee table into a picture of a home environment.
[0038] FIG. 7 illustrates how to adjust the 3-dimensional features of an image based on the distance between the display system and the viewer.
[0039] FIG. 8 a illustrates how object coordinates can be transformed into image coordinates using rotation and translation matrices.
[0040] FIG. 8 b illustrates deriving rotation and translation matrices using a reference object.
[0041] FIG. 8 c illustrates using pose estimation to construct 3-dimensional features and size measurement information.
DETAILED DESCRIPTION
[0042] For an online user who sits in front of her computer browsing sales items on display at a retailer's website, several techniques can be employed to improve her shopping experience. One of the techniques is through the so-called WYSIWYG (what you see is what you get) approach. WYSIWYG effects can enhance real-life effects in graphic display and can makes it possible for an online user to appreciate certain real life features of an object that is on display, for example, the true size of the object.
[0043] To allow an online shopper to experience certain WYSIWYG effects of a 2-dimensional object, the object image can be enlarged or reduced to show the object in its real size or in a given ratio to its real size, such as 50% of the real size. The effect of a 2-dimensional object shown in its real size on the display is the same as if the 2-dimensional object were placed on the display, as shown in FIG. 1 c . If the display is not big enough to show the entire object in real size or in a size of a given ratio to its real size, only a part of the object may be shown in order to fit into the screen. An online browser can select which part to be shown on the display.
[0044] To allow an online shopper to experience WYSIWYG effects of a 3-dimensional object, the object image can be enlarged or reduced to show a chosen 2-dimensional feature of the 3-dimensional object in real size or in a size of a given ratio to its real size. The effect of a 2-dimensional feature of a 3-dimensional object shown in its real size on the display is the same as if the 2-dimensional feature of the 3-dimensional object were placed on the display. As shown in FIG. 1 d , a chosen 2-dimensional feature of the iPhone, the touch screen of the iPhone, is shown in real size on the display. The image of an iPhone is adjusted so that a chosen 2-dimensional feature (the touch screen of the iPhone) in the image is of the same size of the touch screen of a real iPhone. A chosen 2-dimensional feature of the Logitech VX Revolution mouse, the Logitech logo, is shown in real size on the display. The image of a Logitech VX revolution mouse is adjusted so that a chosen 2-dimensional feature (Logitech logo) is shown in its real size on the display. It looks as if a real Logitech VX revolution mouse is placed on the screen. When the object image is enlarged or reduced to show a specific 2-dimensional feature in real size or in a size of a given ratio to its real size, other 2-dimensional features of the object in the same image do not need to be of its real size or of a size with the same ratio to its real size.
[0045] To allow an online shopper to experience WYSIWYG effects of a 3-dimensional object in an image with several other objects, the image will be enlarged or reduced to show a chosen 2-dimensional feature of the chosen 3-dimensional object in real size or in a size of a given ratio to its real size. The effect of the chosen 2-dimensional feature of the chosen 3-dimensional object shown in its real size on the display is the same as if the chosen 2-dimensional feature of the chosen 3-dimensional object were placed on the display. As shown in FIG. 1 e , there are many railroad sleepers in the image. A chosen 2-dimensional feature (the flat section of the top edge) of the 3-dimensional object (the closest railroad sleeper) is shown in 10.46% of real size on a 12.1 inch display with an aspect ratio of 4:3. The user can see the flat section of the top edge of the closest railroad sleeper in 10.46% of its real size on a 12.1 display with an aspect ratio of 4:3. When the image is enlarged or reduced to show a specific 2-dimensional feature in real size or in a size of a given ratio to its real size, other features of the same object in the same image and other objects in the same image do not need to be of real size or the same given ratio to real size. As shown in FIG. 1 e , other sleepers are not in 10.46% of its real size.
[0046] To allow an online user to experience WYSIWYG effects of a 3-dimensional object in a video frame or an image in a series of images, all frames or all images in the series will be enlarged or reduced in the same way to show the chosen 2-dimensional feature of the chosen 3-dimensional object in the chosen frame or the chosen image in its real size or in a size of a given ratio to its real size. As shown in FIG. 1 f , a chosen 2-dimensional feature (the logo of MOTOROLA) of a chosen 3-dimensional object (a Droid phone) in the chosen frame (the frame at the beginning of the 11 th second of a YouTube video is shown in 195% of real size on a 12.1 display with an aspect ratio of 4:3.
[0047] To allow an online user to experience WYSIWYG effects of multiple objects, for example, to get a sense of the objects when they are in comparison with each other, the images and videos of all the objects may be enlarged or reduced. A specific 2-dimensional feature of a specific object will be chosen in each image or video. All images or video containing the chosen 2-dimensional feature will be displayed either with the 2-dimensional feature in real size, or in a size of the same ratio to their real size. As shown in FIG. 1 g , there are four images of e-book readers. A specific 2-dimensional feature (the display of each e-book reader) of a specific 3-dimensional object (e-book reader) in each image is chosen. All chosen 2-dimensional features are shown in 25% of real size on a 12.1 inch display with an aspect ratio of 4:3.
[0048] The above described WYSIWYG effects enhance a viewer's visual experiences. The descriptions below illustrate how a computer application can be implemented to achieve those WYSIWYG effects on a display system. As a first step, the application needs to figure out the configuration of the viewer's display system. In the following discussion, user refers to those who set up and utilize the computer applications implemented based on this present invention in their businesses. An example of a user is an online retailer. A viewer/browser or customer refers to the customers of a user of the applications.
[0049] As shown in FIG. 2 a , an exemplary display system 202 often comprises multiple display elements 222 , 224 , 226 , etc. The display system 202 may be a computer screen, a cell phone screen, a PDA, an iPhone, a monitor, a TV etc. The display elements in most of the display systems that are on the market today are of a uniform size. In the present application, the discussions are based on the assumption that the display elements in a display system are of the same size. However the same techniques and methods can be used on a display system comprised of display elements of different sizes.
[0050] In referring to FIG. 2 a , the display system 202 is of a rectangular shape. Its diagonal line 206 (L) is 12.1 inches long. The display system 202 is composed of a grid of display elements and the resolution of the display system (R 1 ×R 2 ) is set to be 768×1024. Therefore, 768 display elements are arranged along the vertical dimension and 1024 display elements are arranged along the horizontal dimension. The total number of display elements is 768×1024=786,432.
[0051] The display element 204 may be of a shape of rectangle or square.
[0052] For a display system the aspect ratio is defined as the ratio of the length of the display system along the vertical dimension to the length of the display system along the horizontal dimension. The aspect ratio of the display system 202 is D 1 :D 2 .
[0053] For a display system with square display elements, D 1 :D 2 =R 1 :R 2 .
[0054] For a display system with rectangular display elements or square display elements, and with the above described configuration (diagonal line of 12.1 inches and resolution of 768×1024), we can calculate the side 214 (l 1 ) and the side 212 (l 2 ) using the following equations:
[0000]
l
1
=
L
·
D
1
R
1
D
1
2
+
D
2
2
,
l
2
=
L
·
D
2
R
2
D
1
2
+
D
2
2
.
(
1
)
[0055] The length of side 214 (l 1 ) and side 212 (l 2 ) can be calculated using the width and the height of the display system. In this specification, the discussion focuses on using the diagonal size and the aspect ratio of the display system. However the same techniques and methods are applicable in cases when the width and the length of the display system are known.
[0056] The resolution of the display system (R 1 ×R 2 ) can be retrieved from any application or system, for example, the online browser.
[0057] In calculating the size of each display element using Equation (1), one approach may be to retrieve the diagonal size and aspect ratio of the display system from the online browser software or hardware. In one implementation, the online browser software or hardware may obtain the information from the operating system and the operating system may be provided with the information by the display system hardware.
[0058] Another approach may be to ask the user to input the aspect ratio (D 1 :D 2 ) and diagonal size (L) of the display system. In one implementation, the user is presented with a block or a circle on the display and is asked to visually identify whether the block is a square or a rectangle or whether the circle is an ellipse, as shown in element 1001 of FIG. 2 b . The block or circle occupies the same number of display elements along the horizontal and vertical dimensions. The display elements in most display systems are square. If the user identifies that the block is a square or that the circle is not an ellipse, the aspect ratio of the display system can be expressed as D 1 :D 2 =R 1 :R 2 .
[0059] If the user identifies that the block as a rectangle instead of a square, or that the circle as an ellipse, he is then presented with several blocks or circles on the display as shown in FIG. 2 c . The user is asked to identify which block or circle is a square or a perfect circle (i.e., not an ellipse). Each block or circle corresponds to a specific aspect ratio, D 1 :D 2 , for example, 4:3, 3:2, 5:4, 16:10, 16:9, etc. The ratio of the number of display elements on the vertical dimension to the number of display elements on the horizontal dimensional of the block or the circle is (D 2 R 1 )/(D 1 R 2 ). If the user identifies one of the blocks as a square or one of the circles as a perfect circle (not an ellipse), that block or circle can then used to calculate the display aspect ratio based on the expression (D 2 R 1 )/(D 1 R 2 ).
[0060] To figure out the diagonal size of the display system, in one implementation, the user is asked to input the size (as shown in element 1005 of FIG. 2 b ) and visually verify that the input is correct, as shown in FIG. 2 b . To verify that the user input is correct, for example, a 12.1-inch display size is not mistakenly entered as 12-inch, an image of a well-known 2-dimensional object is shown on the screen displayed in a size that is supposed to be its real size calculated based on the user input. The user is asked to bring a real object and place it on the screen in order to verify that the image is of the same size as the real object. The method of displaying the well-known 2-dimensional object in its real size based on the diagonal size of the display (and the size of a display element l 1 and l 2 ) is discussed in Equations (3) and (4).
[0061] The well-known object used in the above discussed method can be any object that is of a standard size and easy to find, such as a driver's license card, a passport, dollar bills, etc. In some implementations, the display system can store the size of a driver's license card (e.g., 3⅜″×2⅛″) as a default value.
[0062] In determining the size of the display element in a display system, one approach may be to ask an online user to place a well known 2-dimensional object on the display and mark the area the real object occupies on the display. For example, as shown in FIG. 2 b , a user places a standard driver's license card (element 1004 in FIG. 2 b ) and uses the mouse or keyboard to mark the area the element 1004 occupies on the display.
[0063] To help the user mark the area the object occupies on the display, in one implementation, the user is asked to place the object at the bottom of the display and to use the display frame to support the object, as shown in FIG. 2 b . In this way, the user does not need to hold the object while marking the area. Assume that the 2-dimensional object is rectangular. When the object is placed at the bottom of the display and uses the display frame for support, the borders of the object are parallel to the borders of the display system frame. Thus it is sufficient to use just vertical lines and horizontal lines to accurately mark the area that the object occupies on the display. The user does not need to mark the bottom of the area the object occupies on the display because the display frame marks the bottom of the area, as shown in element 1008 in FIG. 2 b.
[0064] Furthermore the user is asked to align the left side of the object with a vertical edge of the screen, as shown in the element 1007 in FIG. 2 b . In this way the user does not need to mark the left side of the area the object occupies on the display.
[0065] A dotted line is drawn as element 1006 in FIG. 2 b . The dotted line starts from the left-bottom point of the object which is where the element 1007 and the element 1008 join. For a given point 1011 on the dotted line 1006 , the number of display elements between the left edge and the point 1011 along the horizontal dimension is D left and the number of display elements between the bottom edge (the element 1008 ) and the point 1011 is D bottom , along the vertical dimension. For a display system with aspect ratio D 1 :D 2 and resolution R 1 ×R 2 and a well-known 2-dimensional object with aspect ratio of W object :D object , we have:
[0000]
D
left
:
D
bottom
=
W
object
·
D
2
·
R
1
D
object
·
D
1
·
R
2
.
(
2
)
[0066] For any point on the dotted line 1006 , the ratio of the distance to the line 1007 and the distance to the line 1008 equals to the aspect ratio of the object W object :D object .
[0067] When the user clicks on any point on the dotted line 1006 , the user marks both the top side and the right side of the area that the object occupies on the display.
[0068] When the user clicks on a point 1010 in the area 1002 in FIG. 2 b , which is the area between the left border (line 1007 ) and the dotted line 1006 , a dotted horizontal line is drawn at the point 1010 . The dotted horizontal line intersects with the dotted line 1006 at the point 1011 . The point 1011 can be used to mark both the top side and the left side of the area that the object occupies on the display because for the point 1011 , the ratio of the distance to the line 1007 and the distance to the line 1008 equals to the aspect ratio of the object W object :D object .
[0069] When the user clicks on the point 1009 in the area 1003 in FIG. 2 b , which is the area between the bottom border 1008 and the virtual line 1006 , a dotted vertical line is drawn at the point 1009 . The dotted vertical line intersects with the dotted line 1006 at the point 1012 . The point 1012 may be used to mark both the top side and the left side of the area that the object occupies on the display for the same reason as stated for the point 1011 .
[0070] Therefore, the user is able to mark the area occupies by the object on the display with one simple click on a mouse.
[0071] For a well-known 2-dimensional object with W-inch in width and H-inch in height, it spans an area of S 1 ×S 2 display elements on the display, we can calculate the side 214 (l 1 ) and the side 212 (l 2 ) of a display element (see FIG. 2 a ) using the following equation:
[0000] l 1 =W/S 1 ,l 2 =H/S 2 (3).
[0072] The customer's screen resolution may be stored in his online browser software or hardware. The next time when the customer wants to view pictures with WYSIWYG effects, the current screen resolution is compared with the previous resolution stored in the browser. If the resolution has been changed, or the browser has been moved among screens attached to one display system but with different resolutions, the current display resolution will not be the same as the stored value. The computer application implemented based on the present invention needs to re-calculate the size of each display element, either automatically or based on user input.
[0073] If the width and height of the display are switched, the screen is considered to have been rotated. Thus the application simply switches the width and height of each display element.
[0074] If the width and height are different from the stored values and are not switched, the method described above can be used to recalculate the size of each display element.
[0075] When an online customer zooms in or zooms out on the browser, the size of each display element is adjusted accordingly. During zooming, the size of a webpage is changed by a ratio (r), to preserve the WYSIWYG effect regardless of the zooming level, the size of each display element becomes:
[0000] l 1 =l 1 /r,l 2 =l 2 /r (4).
[0076] Having derived the lengths of the sides 212 and 214 of a display element (l 1 and l 2 ), we can use them to render an image on a display system with desired WYSIWYG effects.
[0077] To simplify our discussion, we will use a 2-dimensional object as an example to illustrate the techniques, and assume that the each display element is a square with length l=l 1 =l 2 . How to apply the techniques to an image of a 3-dimensional object will be discussed later. The same techniques and methods can be used on a display system with rectangular display elements (l 1 ≠l 2 ).
[0078] In FIG. 3 , an image of the front side of an iPhone 302 is rendered on a display system 300 . The image 302 is of the same size of a real iPhone. That is, the length 306 of the image 302 equals to the length of a real iPhone and the width 304 of the image 302 equals to the width of a real iPhone. FIG. 4 a illustrates how this is done when the dimensions of a real iPhone are known before hand.
[0079] As shown in FIG. 4 a , a display system 400 displays an iPhone image 402 . The length 410 and width 408 of a real iPhone are: 4.5″ and 2.2″. Each display element of the display system 400 is a square and of the same size. The length of the side 404 of the display element is l. The number of display elements 414 occupied by the image of the front side of the iPhone along the vertical dimension can be derived using the following equation:
[0000]
v
1
=
4.5
″
l
.
(
5
)
[0080] The number of display elements 412 occupied by the image of the front side of the iPhone along the horizontal dimension is:
[0000]
v
2
=
2.2
″
l
.
(
6
)
[0081] v 1 and v 2 are integers and may be rounded. By plotting an image of an iPhone that spans v 1 display elements in the vertical dimension and v 2 display elements in the horizontal dimension, the display system 400 can render the image of the front side of an iPhone, the image 402 , which is of the same of a real iPhone.
[0082] In today's technology, knowing how many display elements along the horizontal and vertical dimensions is sufficient for displaying a 2-dimensional image either on a LCD screen or a plasma screen or a projector type monitor. In any real-world application of this invention, the images may be far more complicated and the technology may be any of the existing or emerging display technologies, the essence of figuring out where and how to plot each dot boils down to figuring out the distances between two dots or between each dot and a reference point. The distances are often expressed in a number of display elements. The above illustrated examples on how to derive the sides of a rectangle expressed in numbers of display elements can be readily applied to complex examples.
[0083] In the above discussion, the displayed image is an image of an object itself. Often times, pictures (of an object plus its surroundings or background) are used by a display system for displaying. For example, in FIG. 4 b , a picture of a 2-dimensional dwarf rabbit painting is presented on a display system 420 . The picture has a border 428 . Inside the border 428 is an image of a dwarf rabbit. The dwarf rabbit image is of the length x′. The image 422 of the picture has a length 424 (x) and a width 430 (y).
[0084] Suppose a seller of paintings or a website operator would like to generate WYSIWYG effects of the image 422 for his online customers, for example, making the size of the dwarf rabbit painting inside the image 422 matches that of the real rabbit. The seller of the paintings or the website operator may or may not know the length of the real dwarf rabbit painting before hand.
[0085] If the user knows the length of the real dwarf rabbit painting, L rabbit , the ratio that the image of the dwarf rabbit needs to be enlarged is:
[0000]
L
rabbit
x
′
.
[0086] Therefore the length of the entire picture 422 needs to be enlarged to:
[0000]
x
×
L
rabbit
x
′
.
[0000] That means, on the display system, along the horizontal dimension, the number of displaying elements occupied by the picture is:
[0000]
x
×
L
rabbit
x
′
l
.
[0000] Here l is the length of a side of a square display element in the display system 420 , assuming each display element is of the same size.
[0087] Similarly, the number of displaying elements occupied by the picture along the vertical dimension can be derived if the height of the real rabbit painting is known before hand.
[0088] Often the user does not know the length or the width of the real rabbit painting. However the length and the height of the real rabbit can be derived from the configuration of the camera that was used to take the picture of the rabbit. The mathematics employed in the derivation is described below.
[0089] In FIG. 4 c , a simplified camera model 450 is shown. Inside the model 450 , a lens 454 is placed vertical to the axis 452 . The lens 454 has a focal length f and two focal points 458 and 460 are marked on each side of the lens 454 . An object 456 is placed at a distance 462 (d 1 ) in front of the lens 454 . An image 455 is formed at a distance 464 (d 2 ) behind the lens 454 . The height of the object 466 is h 1 and the height of the image 455 is h 2 . The dimension of the object 456 is related to the dimension of the image and the camera configuration as following.
[0000]
h
1
h
2
=
d
1
d
2
,
[0000] wherein
[0000] d 1 ×d 2 =f 2 .
[0090] Therefore, h 1 can be expressed in terms of the known parameters, f, d 1 , and h 2 as:
[0000]
h
1
=
h
2
×
d
`
2
f
2
.
[0091] Now referring to FIG. 5 , we show how, without the knowledge of the size of the rabbit painting, a picture of the painting may be enlarged to show an image of the painting corresponding in size to the real painting. In FIG. 5 , an image based on a photograph 586 is rendered on the display system 580 . In the photograph 586 , the painting image has a length 588 of r 2 and the border of the picture has a length 584 of D 2 . Based on the camera configuration (the distance d where the real 2-dimensional object or a 2-dimensional feature of a 3-dimensional object is placed and the focal length f of the lens), the length of the life-size painting r 2 ′ can be derived from the length of the image of the painting, r 2 , using Equation:
[0000]
r
2
×
d
2
f
2
.
[0000] On the display system 580 , the length of the rabbit image is the same as the length of the rabbit painting r 2 ′. The length of the border of the picture D 2 ′ needs to be enlarged by a ratio of
[0000]
r
2
′
r
2
.
[0092] It should be noted that configurations of real cameras may include other physical parameters, such as the curvature of the lenses, etc., in order to take into consideration the distortions caused by the lenses.
[0093] Once the size of a display element is derived from Equations (3) and (4), a user can apply the above described method in adjusting the size of a picture or an image to achieve WYSIWYG effects. One such effect is to make the image the same size as the real object and applications thereof can be found in internet commerce. As mentioned in the background section, merchandise photos displaying WYSIWYG effects may give internet shoppers the kind of experience similar to that of in-store shopping. Seeing the WYSIWYG effects of a digital camera on display with on the computer screen and believing what he sees is what he gets allows the customer to appreciate the compact design. Seeing a side view of a life-size laptop allows a customer appreciate the thinness or the sleekness of the design. This feature of displaying a sales item with WYSIWYG effects may be implemented as an option that can be turned on or off. This feature may be also used by a search engine. When a user searches for a product, the search engine may choose to display images of the product with WYSIWYG effects. This feature may also be used by a museum to display on its website its rare collection items with WYSIWYG effects.
[0094] The above described method of adjusting the size of an image or images on a display system may also find application in in-store furniture shopping. Software implementing those methods may prove to be handy for a customer who wants to buy a coffee table for the corner space between her sofa and her chair in her home, as shown in FIG. 1 b . Instead of measuring the dimensions of the space to be filled, she takes a picture 602 of the corner with the sofa and chair in view and stores her picture on her portable electronic device, e.g., iPhone, PDA, laptop, etc., or onto a web service website. If the picture is uploaded onto a website, it can be downloaded for later use. The customer takes her portable electronic device with her to a furniture store and sees a coffee table she likes. Not sure whether the coffee table will fit in between her sofa and her chair, she takes a picture of the coffee table.
[0095] An application installed on the portable electronic device then manipulates the two pictures, one of the corner space and the other of the coffee table, with the former perhaps retrieved from a website. For example, using the above described method of adjusting the size of an image, the application can adjust the sizes of the objects in both pictures to be the same as those of the real-life objects. The application can accomplish this based on the measurements the customer inputs or based on the assumption that the pictures are taken with a fixed configuration, i.e., the same focus distance and the same distance between the object and the lens. The application can also adjust the sizes of the images in some other ways, e.g., trying to fit everything into the screen of the portable electronic device.
[0096] After the two pictures are adjusted to reflect a same ratio enlargement or reduction in size, the customer can superimpose the picture of the coffee table onto the picture of the corner space, as shown in FIG. 5 , to see whether the coffee table fits into the corner space not only geometrically but also aesthetically, such as in matching color scheme or complimentary fashion style.
[0097] In some implementations, a picture can be superimposed onto a live camera feed. For example, a customer already has a TV stand at home. He takes picture(s) of his TV stand and measures its size. Then the customer goes to a store and finds a TV he wants to purchase. The customer tells his iPhone, literally or figuratively, about the model of the TV. For example, he can use an iPhone application to scan the TV product bar code or simply type in or speak the model name. The customer then opens the iPhone camera, points his iPhone at the TV and captures the image of the TV on the iPhone screen. The iPhone then pulls out the customer's TV stand picture taken at home which is either stored locally on the iPhone or remotely on a website, and superimposes the TV stand image onto the TV image. The TV stand image is adjusted to make the TV stand appear to be there in the store. By adjusting the position of the TV stand on his iPhone screen, the customer can position it beneath the TV. Now the customer is able to see how well the TV he wants to purchase fits in his home without bringing home the TV.
[0098] In another example, a user uses her iPhone camera to record an event. While the camera is rolling, the user imposes a static image onto the live recording. The image may be enlarged or reduced as desired and the live recording may be adjusted in size accordingly.
[0099] Allowing customers to apprehend the true size of a sales item is one of the innovative ways that can be utilized to enhance online shoppers' shopping experience and let them enjoy the kind of in-store shopping experience in the comfort of their homes. Allowing customers to appreciate the 3-dimensional features of a sales item can also improve an online shopper's shopping experience.
[0100] For example, one method that can be used to present a 3-dimensional view of a piece of merchandise, e.g., a vehicle, is by taking photos of the vehicle from different angles. The photos are then flashed on a display system in a sequential manner to present a rotating vehicle.
[0101] Another method that can be utilized to allow customers to appreciate the 3-dimensional features of a sales item is by adjusting the 3-dimensional features of a photo of a sales item to make it appear more realistic.
[0102] In the above sections when we discuss adjusting the size of an image to make the 2-dimensional or 3-dimensional object in the image appear the same or approximately the same as the real object, we focus on 2-dimensional images, for example, the front side of an iPhone as shown in FIG. 4 a . However, some pictures of a real object may contain 3-dimensional features of that object or 3-dimensional features of the environment where the object is situated, for example, the thickness of the iPhone or the surrounding wall. When an image of an object is adjusted on a display system to make the object appear with WYSIWYG effects, the 3-dimensional features present in the image also need to be adjusted to make the entire image appear realistic. An elaborate method based on Equations (7) and (8) can be applied to reconstruct every 3-dimensional feature contained in the image when that image is adjusted to reflect a size of the object that is or is close to its true size.
[0103] FIG. 1 e explains how Equations (7) and (8) are derived. In FIG. 1 e , a disappearing railway 170 is made of two converging steel rails, 172 and 182 , and sleepers, e.g., 174 , 176 and 178 , waning in size.
[0104] In FIG. 1 e , the lengths of the sleepers, 174 , 176 and 178 are expressed as S 1 , S 2 , and S 3 . The distance between two adjacent sleepers is d, assuming the sleepers are evenly spaced. The distance between the location of a view and the sleeper 174 is D (not shown). Based on the mathematics of Perspective Geometry, the relationship between the lengths of the sleepers can be expressed approximately as:
[0000]
S
1
S
2
=
D
+
d
D
,
and
(
7
)
S
2
S
3
=
D
+
2
d
D
+
d
.
(
8
)
[0105] In referring to FIG. 1 e , when the length S 1 of the sleeper 174 is set, the rest of the pictures, such as the sleepers 176 and 178 can be drawn in appropriate proportions in relation to the sleeper 174 based on Equation (7) and (8). The length S 1 of the sleeper 174 can be set to the true length of the sleeper if it is desired. But it can also be set differently as may be required by different applications.
[0106] As shown in FIG. 7 , a computer user 750 is engaged in online shopping. A photo of a sales item, for instance, a jewelry box 754 , is on display. The image has been processed to make the front side of the jewelry box 756 in the image the same size of the real object. The rest of the image, including the 3-dimensional features of the jewelry box 754 , such as the partitioned interior 758 , the elaborate decoration 760 on the side, should be adjusted accordingly to make the entire image appear realistic to the computer user 750 .
[0107] Based on the assumption that the distance 752 between the computer user 750 and the display system 751 , e.g., a computer screen, is D, the enlargement or the reduction of the features in the rest of the image may be carried out according to Equation (7) or (8), either feature by feature or point by point. In Equation (7), d represents the distance between the feature or point to be processed and the front side of the jewelry box.
[0108] In some implementations, the distance D between the computer user 750 and the display system 751 may be determined in real-time. A camera or a distance sensor may be used to determine how far a computer user is away from the display system. When the computer user moves closer to or away from the display system, the change of the distance D is monitored and fed to the display system to be used for image re-adjustment. In other implementations, approximation may be used to reduce computation time and increase efficiency. For example, the distance D may be assumed to be constant and take a value that reflects the computer using habit of an average computer user. Or the distance D may be assumed to be zero for simplicity.
[0109] As described above, to display images of an object on a display system for WYSIWYG effects, the method of making the object in the image the same size as the real object or approximately the same size as the real object may be employed. When the image is adjusted to make the image the same size as the real object, the perspective 3-dimensional features included in the image should be adjusted accordingly based on how far the viewer is positioned. Perspective 3-dimensional features can enhance real-life effects of any picture. When a picture lacks any or some of the 3-dimensional features, pose estimation techniques can be used to generate 3-dimensional features for the picture to create real-life effects. For example, a picture of an object taken by just one camera often lacks 3-dimensional effects. Pose estimation techniques can be used to re-construct a 3-dimensional model and size measurement information of that object in order to generate another picture of the object with realistic 3-dimensional effect
[0110] FIGS. 8 a - 8 b explain how pose-estimation can be used to generate 3-dimensional features. In pose-estimation, a reference object is used to calibrate the camera. The reference object and the target are posed together in one picture.
[0111] In FIG. 8 a , translation matrix T 816 and rotation matrix R 818 are two extrinsic parameters that describe how the camera transforms an object from a real object into an image. For illustration purpose only, the process is explained using one reference point O w . O w is a reference point in the real world and is transformed by the camera lens system into a point O i which is then imaged onto the image plane 806 . From O w to O i , the transformation can be expressed as:
[0000]
(
x
i
y
i
z
i
)
=
R
×
(
x
w
y
w
z
w
)
+
T
,
(
9
)
[0112] where
[0000]
(
x
i
y
i
z
i
)
[0000] is the 3-dimensional coordinates of O i and
[0000]
(
x
w
y
w
z
w
)
[0000] is the 3-dimensional coordinates of O w . Translation matrix T 816 can be expressed as:
[0000]
(
T
x
T
y
T
z
)
.
[0000] with (T x , T y , T z ) standing for the 3-dimensional translation from O w to O i .
[0113] And rotation matrix R 818 can be expressed as:
[0000]
(
cos
(
R
y
)
cos
(
R
z
)
cos
(
R
z
)
sin
(
R
x
)
sin
(
R
y
)
-
cos
(
R
x
)
sin
(
R
x
)
sin
(
R
x
)
sin
(
R
y
)
+
cos
(
R
x
)
cos
(
R
x
)
sin
(
R
y
)
cos
(
R
y
)
sin
(
R
z
)
sin
(
R
x
)
sin
(
R
y
)
sin
(
R
z
)
+
cos
(
R
x
)
cos
(
R
z
)
cos
(
R
x
)
sin
(
R
y
)
sin
(
R
z
)
sin
(
R
x
)
-
sin
(
R
y
)
cos
(
R
y
)
sin
(
R
z
)
cos
(
R
x
)
cos
(
R
y
)
)
,
[0114] with (R x , R y , R z ) standing for the Euler angles of the rotation from O w to O i .
[0115] In FIG. 8 a , point O i is projected onto the image plane 806 as point P u (x u , y u ) with x u and y u being P u 's coordinates on the image plane 806 . If taking into consideration of the distortions caused by the camera, the image point of O i may be formed at P d , which is slightly displaced from P u . We assume no distortion in the following discussion.
[0116] (x u , y u ) is related to (x i , y i , z i ) as following.
[0000]
x
u
=
f
x
i
z
i
;
(
10
)
y
u
=
f
y
i
z
i
,
(
11
)
[0117] with f being the focal length of the lens system of the camera. If (d x , d y ) represents the distance between adjacent sensor elements, then the coordinates of the image point O i can be expressed in terms of sensor elements (x f , y f ) as:
[0000]
x
f
=
x
u
d
x
;
(
12
)
y
f
=
y
u
d
y
;
(
13
)
[0000] with the assumption that there is no lens distortion and hardware imperfection.
[0118] Based upon the mathematical relations described above, a calibration procedure can be used to construct rotation matrix R and translation T. FIG. 8( b ) illustrates an example of such a calibration procedure.
[0119] In FIG. 8( b ), a checker board 840 is used as a reference object. The checker board 840 is placed in front of the camera. Two points on the checker board are selected for the calibration process. The coordinates of the point 846 are (a w , b w , c w ) and those of the point 848 are (a w ′, b w ′, c w ′). Because the checker board 840 is placed parallel to the image plane (not shown), we have c w =c w ′=z. The image 844 of the checker board 840 is formed inside the camera 842 and is enlarged on the left for illustration purposes. The point 846 is imaged into a point 850 with coordinates (a u , b u ) and the point 848 into a point 852 with coordinates (a u ′, b u ′).
[0120] Using Equations (10) and (11), we get
[0000]
a
i
=
a
u
×
c
i
f
,
b
i
=
b
u
×
c
i
f
and
a
i
′
=
a
u
′
×
c
i
′
f
,
b
i
′
=
b
u
′
×
c
i
′
f
[0000] with f representing the focal length of the camera lens and
[0000]
c
i
′
=
c
i
=
f
2
z
.
[0121] From Equation (9), we get:
[0000]
(
a
i
b
i
c
i
)
=
R
(
a
w
b
w
c
w
)
+
T
,
and
(
a
i
′
b
i
′
c
i
′
)
=
R
(
a
w
′
b
w
′
c
w
′
)
.
[0122] Because (a u , b u ), (a u ′, b u ′), (a w , b w , c w ), (a w ′, b w ′, c w ′), f, and z are known parameters, solving the above two equations yields the rotation matrix R and translation matrix T for the camera. With R and T, pose estimation may be readily carried out as shown in FIG. 8 c.
[0123] In FIG. 8 c , a real object 882 has a front side 884 and side or hind features such as DE. By using just one camera, the front side of the object 882 is captured and presented in the picture 883 as the front side 886 . Pose estimation will allow some of the 3-dimensional features of the object 882 that are not captured in the picture 883 to be reconstructed and filled in by an application. For example, line D′E′ in picture 886 corresponds to line DE shown in the picture 882 , with
[0000]
D′E′=R×DE+T.
[0124] Other 3-dimensional features in the picture 882 can be similarly constructed and presented in the picture 883 . Instead of using multiple cameras as conventional methods would require, the above described process uses just one camera to construct images and generate measurement information (such as the length of the feature DE) of 3-dimensional objects.
[0125] The techniques described herein can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The techniques can be implemented as a computer program product, i.e., a computer program tangibly embodied in a storage medium. A computer program can be written in any form of programming language and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.
[0126] The techniques described herein can be implemented in a distributed computing system that includes a back-end component, e.g., as a data server, and/or a middleware component, e.g., an application server, and/or a front-end component, e.g., a client computer having a graphical user interface and/or a Web browser through which a user can interact with an implementation of the invention, or any combination of such back-end, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet, and include both wired and wireless networks. The computing system can include clients and servers. A client and server are generally remote from each other and typically interact over a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.
[0127] Method steps of the techniques described herein can be performed by one or more programmable processors executing a computer program to perform functions of the invention by operating on input data and generating output. Method steps can also be performed by, and apparatus of the invention can be implemented as special purpose logic circuitry. Modules can refer to portions of the computer program and/or the processor/special circuitry that implements that functionality.
[0128] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. Information carriers suitable for embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM; and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in special purpose logic circuitry.
[0129] Other embodiments are within the scope of the following claims. The above are examples for illustration only and not to limit the alternatives in any way. The techniques described herein can be performed in a different order and still achieve desirable results. | Embodiments of the invention provide methods, systems, and articles for displaying objects in images, videos, or a series of images with WYSIWYG (what you see is what you get) effects, for calibrating and storing dimensional information of the display elements in a display system, and for constructing 3-dimensional features and size measurement information using one camera. Displaying merchandises with WYSIWYG effects allows online retailers to post vivid pictures of their sales items on the Internet to attract online customers. The processes of calibrating a display system and the processes of constructing 3-dimensional features and size measurement information using one camera are applications of the invention designed to achieve desired WYSIWYG effects. | 6 |
BACKGROUND OF THE INVENTION
Heating appliances with an improved efficiency (IE) and high efficiency (HE) are in large scale use in the Netherlands and elsewhere for heating dwellings and other accommodation areas. For many dwellings it is important that such heating appliances take the most compact possible form, while it must be avoided that the appliances are so complicated that regular, costly servicing and maintenance has to take place.
These known heating appliances have a number of drawbacks, a number of significant ones being: the size of the appliances, whereby they are difficult to build into a cupboard or the like; the emission of CO and NO x as well as the associated efficiency loss, for instance because considerable temperature differences are present inside the apparatus.
SUMMARY OF THE INVENTION
The present invention provides an apparatus for heating fluid, comprising:
first supply means for supplying fuel;
second supply means for supplying oxidizing agent;
burner means for combusting fuel and oxidizing agents after mixing thereof; and
a first heat exchanger to be heated by flue gases of the burner means and arranged helically round the burner means.
A heating appliance is obtained with the present invention which can be embodied compactly and wherein emissions and efficiency loss are limited.
Preferred embodiments of the apparatus relate to further improvements in efficiency and reduction in emission of undesired combustion products by precise guiding of the combustion products along the heat exchanger.
A jacket provided with openings is preferably arranged round the helical heat exchanger in order to enable a good heat exchange between the combustion gases and the pipes of the heat exchanger. These openings can be round or slot-shaped and are preferably arranged behind the helically running pipe of the heat exchanger. The jacket may also be formed from wound strips or band of metal between which openings are left clear.
In a so-called combi-appliance is included an insulated tank or reservoir of relatively small dimensions from which hot tap water is immediately available. A compact combi-appliance with a power of for instance 22-24 kW has to be capable of providing 6 liters of water per minute at 60° C. from this insulated storage tank. In the known combi-appliances however, it is found in practice that, while water at 60° C. is supplied for a short time, the temperature of the tap water thereafter decreases and a constant value above 60° C. is reached only after for instance one minute. This is particularly the case if the heating appliance is not used or is used to a lesser extent (as according to so-called modulating operation) to heat fluid in pipes and radiators of the heating system in the dwelling. Although a preferred embodiment of the present invention is provided with such a reservoir, another preferred embodiment is provided with a heat exchanger which takes up little space.
The present invention further provides an apparatus which is provided with a reservoir for temporarily storing heated water, wherein the reservoir comprises a second heat exchanger which is operationally coupled to the first heat exchanger.
The first heat exchanger will preferably be provided in the future with an inner pipe and an outer pipe, whereby the tap water is further heated in the inner pipe.
The apparatus according to the present invention is preferably provided with a third heat exchanger which is arranged in the discharge duct for the heated flue gases and which serves to preheat the tap water.
The preferred embodiment with a reservoir is preferably provided with pump means for pumping medium round in the heating circuit provided with a rotation speed regulation, or at least an ON/OFF control, wherein the pump action is reduced or interrupted at the moment wherein hot water is demanded from the hot water reservoir by the user, or immediately thereafter, whereby, in the case the apparatus is not used for heating purposes, the relatively cold water from the first heat exchanger is prevented from entering the reservoir. If necessary, the burner is started and the first heat exchanger heated, whereafter the pumping action of the pump means is increased.
The flue gases are preferably urged closely along the first heat exchanger for exchange of heat between the flue gases and the heat exchanger with the greatest possible efficiency, wherein for this purpose the side walls of the annular space preferably have a contour at least partially adapted to the outer contour of the heat exchanger in order to further increase a laminated gas flow along the heat exchanger.
As well as for room heating, thermal energy is also required in a dwelling for a number of other purposes, for instance for cleaning, such as hot air for a tumble dryer or dish washer and the like, and also for cooking and the heating of ventilation air for circulation in a dwelling. This thermal energy is generated in most dwellings using electricity, which is disadvantageous from an energy efficiency viewpoint.
The present invention therefore further proposes to provide the above stated apparatus with a heat exchanging unit which is arranged in heat-conducting contact with the top part of the apparatus and which is provided with an inlet for infeed of medium for heating and an outlet for heated medium.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages, features and details of the present invention will be elucidated on the basis of the following preferred embodiments thereof with reference to the annexed drawings, in which:
FIG. 1 shows a partly cut-away view in perspective of a preferred embodiment of an apparatus according to the present invention;
FIG. 2 shows a graph illustrating the operation of the preferred embodiment of FIG. 1;
FIG. 3 shows a partly broken-away view in perspective of an alternative embodiment of the reservoir shown in FIG. 1;
FIG. 4 is a partly sectional and partly broken-away view in perspective of an alternative embodiment of the burner and primary heat exchanger of FIG. 1;
FIG. 5 is a partly broken-away side view of an alternative embodiment of the primary heat exchanger of FIGS. 1 and 4;
FIG. 6 is a partly broken-away view in perspective of the fixing to a wall of a preferred embodiment of the apparatus according to the present invention;
FIG. 7 shows a diagram of a further preferred embodiment for use of the apparatus according to the present invention;
FIG. 8 shows a front view of a further preferred embodiment of the present invention; and
FIG. 9 shows a view in perspective of a further preferred embodiment of a reservoir for hot water for use in an apparatus according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
A heating apparatus 1 (FIG. 1) comprises a feed line 2 for gas with a schematically designated gas regulation 3 in addition to a schematically designated fan 4 for feed of air to a burner 5 where the gas is mixed with the air and combusted. The gas and the air are mixed in a substantially hollow cylindrical inner sleeve 6 which may be provided with mixing means (not shown) and which is provided with openings which debouch in a combustion space around which a heat exchanger 8 is disposed, which space is enclosed by a substantially cylindrical outer sleeve 9 closed at the top. The gases are deflected in downward direction and guided along heat exchanger 8 between the outer wall of inner sleeve 6 and the inner wall of outer sleeve 9. Both the inner wall of outer sleeve 9 and the outer wall of inner sleeve 6 are preferably adapted slightly in shape to the annular pipes of heat exchanger 8 so that a good heat exchange takes place between the hot gases and the content of the heat exchanger.
The helical heat exchanger 8 preferably comprises an inner pipe 10 and an outer pipe 11. Arranged on the inner pipe for good heat transfer are star-shaped fin parts 10a which make heat-conducting contact with outer pipe 11. Flowing through inner pipe 10 is so-called tap water which can be drawn off as hot water in a household using a tap and which is supplied via a pipe 12. Tap water pipe 12 ends at connecting piece 13 onto which also connects a supply line 14 which, via a three-way valve 16 and a pump 15, connects onto the circuit of a central heating system via a feed line 17 and a discharge line 28.
In the present embodiment the tap water is further supplied via a line 18 which, for preheating of the tap water which has for instance a temperature of 5-15° C., is arranged via a folded heat exchanger 19 in a discharge part 20 for the flue gases. After flowing through the inner pipe 10 of heat exchanger 8 the tap water is guided via coupling piece 21 and line 22 to reservoir 23 for temporary storage thereof, so that hot water is immediately available to the user when a tap is opened. Reservoir 23, which is well insulated in a manner not shown, is provided with an inner sleeve 24 so that incoming tap water is first of all driven in upward direction as according to arrows C and subsequently flows between outer wall 25 of the reservoir and inner sleeve 24 to drain stub 26 for drawing off the tap water (arrow D).
Arranged in the annular interspace of reservoir 23 is a second heat exchanger 27 through which flows the fluid of the central heating installation supplied via lines 28, three-way valve 16 and line 29.
The apparatus according to the present invention is preferably provided in a manner not shown with a control unit which controls three-way valve 16, pump 15 and gas regulation 3. Three-way valve 16 is controlled either to heat the medium in an internal circuit or for use wherein heat must be supplied continuously to the central heating circuit and the feed and discharge line of this central heating circuit are in continuous connection thereto.
The curve in the graph of FIG. 2 shows that when tap water is drawn off in a dwelling with a pipe of determined length between draw-off point and apparatus according to the present invention, the temperature is at a level of 60° C. within ±15 seconds and also no longer falls below this level. During this measurement it has been found that it is advantageous to slightly delay starting of the pump for the primary heating fluid, for instance for a duration of 5-15 seconds, or to set it at a lower pumping level when the burner has to be set into operation to supply the demanded amount of heat. Cold water still present in the heat exchanger is thus prevented from entering the reservoir before being heated.
In a further preferred embodiment the apparatus according to the present invention is provided with a reservoir 50 (FIG. 3) for tap water which can be manufactured more simply and at lower cost than the reservoir 23 of FIG. 1. The tap water for heating is guided via a feed line 51 on the underside of reservoir 50 into a groove between two successive windings 52 and 53 of a helical plate 55 arranged on an outer jacket 54, so that the supplied tap water is preheated before entering the interior of a heat exchanger 56 via an inlet opening 57. An outlet line 58 on the underside of heat exchanger 56 is connected onto the interior thereof for draining of the heated tap water.
In an alternative embodiment (not shown) the helical plate 55 can be replaced by a plurality of concentric discs arranged one above another and having openings for passage of water.
Heat exchanger 56 comprises a large number of substantially upright pipes which are connected via a distributor (not shown) to a feed line 59 for hot central heating water. At the top the upright pipes debouch into a central return pipe 60 onto which connects a discharge line 61 for the central heating water.
In an alternative embodiment of an apparatus according to the present invention (FIG. 4) a helical heat exchanger 68 is arranged in a space defined by an outer sleeve 65, a cover 66 and an inner sleeve 67, which heat exchanger comprises an outer pipe 69 and an inner pipe 70. In order to increase the combustion efficiency the air supplied via a fan 71 is mixed with gas supplied via a feed connection 72 by means of a plurality of horizontally disposed plates 73, 74, 75, 76 respectively which are provided in each case with passage openings which are in shifted arrangement in successive plates in order to obtain a well mixed, turbulent flow of the mixture combusted in a burner 77. The gases leaving burner 77 are guided along the pipes of heat exchanger 68 and discharged on the underside via an outlet 78 for the flue gases. Due to the good mixing of air and gas a complete combustion of the mixture is achieved whereby the emission of CO and No x is avoided as far as possible. In order to prevent excessive heating of the inner pipe a closed baffle plate 80 is preferably arranged above the plates 73-76 provided with openings.
Arranged in a further preferred embodiment between an outer jacket 85 (FIG. 5) and a helical pipe 88 is an intermediate jacket 89 of substantially cylindrical form in which openings 87 are arranged in accordance with the pitch of the helical pipe of heat exchanger 88. In a manner not shown the pipe 88 can be provided with fins or plate-like protrusions in order to increase heat transfer. Due to the location of the openings 87 at the position of the centre line of the helical pipe, the flue gases are urged to flow as closely as possible along the periphery of the helical pipe of the heat exchanger before arriving in an interspace 90, along which the flue gases are discharged downward. In order to further increase efficiency, partitions 91, 92 provided with openings are further arranged along the lower helical windings of heat exchanger 88, whereby the flue gases flow further along the heat exchanger.
For installation and servicing operations it is important that the apparatus according to the present invention, which can be embodied very compactly, can be mounted in simple manner on a wall, for instance in a cupboard, while the accessibility to the interior of the cupboard must be ensured. According to a preferred embodiment of the present invention a cupboard 93 (FIG. 6), preferably consisting of a front part 94 which is removable and a rear part 95, is fixed via this rear part to a strip-like plate 96 which is mounted on a wall W using screw bolts such as 97 and suspended therefrom. For this purpose a plate 98 is fixed, preferably welded, to the rear part 95, which plate engages behind a hooked end 99 in strip-like plate 96 and is hung thereon. In addition, the underside of the rear part 95 is supported on a profile 100 of substantially U-shaped cross-section to which the feed and discharge lines for central heating water and tap water can be fixed using clamping brackets 101, 102 etc. The diverse components, such as control electronics 103 and other components (not shown) such as the heat exchangers and the reservoir for the tap water, are preferably arranged on the rear part 95 of cupboard 93 fixed firmly to wall W, for instance by means of brackets 104 placed therein. In another preferred embodiment (not shown) the rear part 95 of the cupboard can be provided on the underside with pins which engage in recesses in bracket 100 whereby cupboard 93 is also prevented from being able to tilt forward because of its weight.
In the embodiment of the present invention of FIG. 7, a further heat exchanger is arranged at the top of the apparatus 1 according to the present invention, which heat exchanger is placed in conducting contact with for instance the discharge part 20 for the flue gases. At the entrance to this further heat exchanger 40 relatively cool air L is introduced, wherein the heated air is carried via arrows M and N respectively into a dryer 41 for drying laundry in energetically responsible manner.
In the embodiment according to FIG. 8, in addition to the burner construction 120 (such as that in FIG. 5) with schematically designated mixing means 121, a heat exchanger 122 is arranged instead of a reservoir for tap water, whereby the invention can be embodied in even more compact manner. At the top the apparatus 125 is provided with preferably slidable connecting pieces 126 and 127 for easy connection of the air feed and the discharge of the combustion gases. The diverse connections for central heating water, gas and mains water are arranged at the bottom. These connections are preferably clamped between a formed piece on the cupboard and a counter-piece fixedly screwable thereon so that the diverse components can be assembled in a cupboard in lying position, whereafter the counter-piece is screwed fittingly into place over the connections. This facilitates assembly and installation operations.
Most probably because of the good thermal balance, whereby large thermal differences do not occur in the compact design of the apparatus according to the present invention, it has been found that the emission of NO x and CO in this appliance according to the present invention have extremely low values. Measurements have shown that the efficiency of the apparatus according to the present invention amounts to theoretically 100%, in any case considerably more than 95%, while the emission of CO and NO x is very low (maximum ca. 95 ppm (at 32 kW) respectively ca. 13 ppm (at 32 kW)).
A further preferred embodiment for a so-called draw-off pot for hot water (FIG. 9) is constructed from a substantially cylindrical vessel 130 which can be of metal but which is preferably assembled from two plastic shells respectively 131, 132 which can be fixed releasably to each other with connecting means (not shown) such as bands or screw bolts in order to open and clean the reservoir in the case of lime scale. Arranged in vessel 130 is a helical metal tube 133, preferably of metal, around which is arranged a pipe or hose 134 of for instance thin plastic (wall thickness of for instance less than 1 mm). Via connecting stub 135 hot water is carried out of the heating system into the helical inner pipe 133, while the water is returned to this system at the top via connecting stub 136. The tap water for heating is carried via connecting stub 137 into vessel 130, while that water in the interspace between the plastic hose 134 and the helical inner pipe 133 is guided downward via the top part into connecting stub 138 to which a hot water line is connected. Spacers are arranged in a manner not shown at determined locations between inner pipe 133 and plastic hose 134 in order to prevent the passage for the water to be heated from being blocked. A temperature sensor is likewise arranged in the vessel in a manner not shown close to connecting stub 137, which sensor senses whether the temperature of the water in the vessel falls below for instance 40° C., whereafter hot central heating water must be supplied. The water for heating is first preheated during the upward movement thereof, while it is heated very strongly during the downward movement between helical pipe 133 and plastic hose 134. Because use is made of a plastic hose arranged round the helical inner pipe 133, a heat exchanger is obtained which is extremely favourable in terms of cost, while for the inner pipe use can be made of standard, commercially available elements. The structure is so compact that it can be incorporated in the compact heating appliances described in the foregoing.
The present invention is not limited to the above described preferred embodiments thereof. Many modifications can be envisaged within the scope of the present invention, which is defined by the following claims. An example of such a non-limiting modification is the placing of a second tap water reservoir in the appliance according to the present invention, since space is still available in the inner space thereof and the stable high temperature of the tap water can thereby be ensured even more precisely. | Apparatus for heating fluid, comprising a first supply for supplying fuel, a second supply for supplying oxidizing agent, a burner for combusting fuel and oxidizing agents after mixing thereof and a first heat exchanger to be heated by flue gases of the burner and arranged belically round the burner. | 5 |
BACKGROUND OF THE INVENTION
1. Field Of The Invention
This invention relates to protective devices for positive displacement pumps, and more particularly, to a protective cover assembly having a reverse buckling disc which buckles rather than shears when subjected to excessive pressure.
2. Description Of The Prior Art
It is common practice in the petroleum industry to employ high pressure plunger-type pumps in a variety of field operations relating to oil and gas wells, such as cementing, acidizing, fracturing and others. An example of such a high pressure pump is the Halliburton Services HT-400 Horizontal Triplex Pump manufactured by Halliburton Services of Duncan, Okla. Such pumps commonly generate pressures in excess of 10,000 psi, and are on occasion subject to overpressuring for a variety of reasons. Several common causes of overpressure are blockage of a pump discharge line, the erroneous closure of a valve on the discharge side of the pump, or the phenomenon of "sandout".
Sandout may occur during a fracturing job, wherein the producing formation of the well is subjected to high pressures to "fracture" the producing strata. It is common in such fracturing operations to include a proppant, such as glass or ceramic beads, walnut shells, glass microspheres, sintered bauxite, or sand (hereinafter collectively and individually referred to as "sand") in the carrier fluid, so as to provide a means of maintaining the cracks in the fracturing producing formation open after the fracturing pressure is released. Present day fracturing operations often employ a foamed carrier fluid such as nitrogen or carbon dioxide as the gaseous phase of the foam, in order to lower the volume and cost of the chemicals required and in many cases to avoid a large hydrostatic force on a well formation, such as is often encountered in gas wells.
There has also recently been a marked tendency to load up the carrier liquid with as much sand as possible prior to foaming, in order to further lower fluid volume requirements and hence job costs to the customer. Such concentrations may reach and exceed sixteen pounds of sand per gallon of carrier fluid. These high sand concentrations impose severe performance demands on the blender, manifold and pump systems due to the erosive effect of the sand and the tendency of slugs of sand to collect in valves, elbows, and in the fluid ends of the high pressure pumps. A collection of sand in these areas is dependent upon a number of parameters, including gravity, fluid flow rate, rheological properties of the carrier fluid, physical properties of the sand, and the geometry of the system as a whole.
However, regardless of causation, the concentration of sand associated with the sandout in the fluid end of a high pressure pump can result in sudden overpressuring of the fluid end with resulting damage to one or more of the plunger, connecting rod, crankshaft, fluid end or other parts of the pump drive train. The overpressuring due to sandout is particularly destructive as the resulting force may be eccentrically applied to the plunger and fluid end, as a slug of sand often collects at the bottom of the plunger.
It has been well known in the art to attempt to alleviate this sandout problem with ball-type valves in the pumps. However, such valves are susceptible to clogging due to the sand content of the carrier liquid, and may also fail to reclose after the problem is corrected due to the presence of sand in the valve or the erosive effect of the sand laden carrier fluid.
Another solution to the overpressuring problem is disclosd in U.S. Pat. No. 4,508,133 to Hamid, assigned to the assignee of the present invention. This invention comprises a protective cover assembly including a substantially circular cover having a shear disc surrounded by an annular outer portion, mounted in a cylinder in the fluid end of the plunger-type high pressure pump. An arcuate boundary of reduced wall thickness lies between the shear disc and the outer portion of the cover. The cover is held in place by a retainer assembly which is secured to the fluid end, which retainer assembly includes a plug backed by an impact disc at the outer end of the retainer. When a predetermined force is generated by the plunger and the cylinder, the shear disc of the cover shears and is propelled outwardly against the plug, which in turn forces the impact disc against the edge of a circular recess in the outer end of the retainer, the recess being of lesser diameter than the impact disc. The impact disc, in shearing against the recess edge, safely dissipates the kinetic energy of the shear disc, while the pressure in the cylinder vents to the atmosphere, avoiding damage to the fluid end of the pump, the plunger, connecting rod, crankshaft, etc., as well as potential damage to the well head. However, the retainer employed with a protective cover is expensive to construct, and in order to refurbish a sheared cover and retainer assembly, a new impact disc as well as a new cover must be available. Moreover, the use of a destructible impact disc to absorb energy adds to the operating costs of the pump in which they are employed.
U.S. Pat. No. 4,520,837 to Cole et al., also assigned to the assignee of the present invention, discloses a protective cover with a shear disc essentially the same as in Hamid, but also includes a more simple, one-piece cover retainer inserted behind the protective cover. When the shear disc is subjected to a load in excess of the shear strength of the arcuate boundary thereon, the cover shears along the boundary and the shear disc is propelled outwardly by the pressure in the fluid end into the cover retainer, the interior of which is of substantially frustoconical configuration, with the base of the cone oriented substantially coaxially with respect to the shear disc. The kinetic energy of the shear disc is substantially dissipated by the contact of the periphery of the disc with the ever decreasing diameter inner wall of the retainer, which plastically deforms the shear disc. The fluid end of the pump, the plunger, connecting rod, crankshaft, etc., are saved from harm by the venting of the overpressure when the disc shears. After the cover retainer with the trapped shear disc and the sheared cover outer portion are removed from the fluid end of the pump, the sand is cleared from the fluid end (if sandout is the cause of the overpressure), a new protective cover is installed, the cover retainer resecured to the fluid end, the pump restarted and the fracturing operation recommenced.
While the apparatus of Cole et al. has advantages over the apparatus of Hamid, there are still a number of problems remaining. First of all, the shear disc is subjected to cyclic loading. This cyclic stress causes fatigue and premature failure of the disc around the thin arcuate wall may occur even at low pump pressures. Another problem is that the thin area around the arcuate portion does not leave much thickness for corrosion allowance, and thus may fail prematurely when corrosion is present. A further problem with the previous apparatus is that the shear disc is expensive to fabricate, and machining will invariably leave machine marks which act as stress risers and compound the fatigue problem already mentioned.
The present invention solves these problems by providing a protective cover assembly with a reverse buckling disc which has a convex surface exposed to the pressure in the pump and thus is loaded in compression only. This greatly improves fatigue life. The convex shape of the disc is easily stamped, thereby eliminating machining marks and the problems related therewith. Because there is no thin section, corrosion is not a great problem.
Another advantage of the present invention is that, under normal circumstances, no fluid is vented out of the pump because of the buckling action of the reverse buckling disc.
SUMMARY OF THE INVENTION
The protective cover assembly of the present invention is adapted for use in a fluid end of a plunger-type or other positive displacement pump and comprises a cover positionable in an outer end of the fluid end, the cover including buckling relief means for buckling in response to overpressure in the pump and thereby relieving the overpressure without venting fluid externally of the pump, and retainer means for retaining the cover in the outer end.
The buckling relief means is best characterized by a domed portion of the cover having a convex surface generally facing a plunger of the pump and adapted for buckling away from the plunger in response to pressure in the fluid end of the pump. Preferably, the convex surface is substantially hemispherical. In one embodiment, the domed portion has a substantially constant cross-sectional thickness. In another embodiment, the domed portion has an enlarged section adapted for affecting the pressure level required for buckling the domed portion.
The retainer means is characterized by a cover retainer engaged with the fluid end of the pump which clamps against an outer portion of the cover. The cover retainer has a substantially frustoconical inner wall for containing the buckling relief means and dissipating kinetic energy thereof in the event of rupture, rather than buckling, of the buckling relief means.
The protective cover assembly may also comprise sensing means for sensing buckling of the buckling relief means and interrupting power delivered to the pump in response to the buckling.
A sealing means is disposed between the outer portion of the cover and the fluid end. In one embodiment, the sealing means is characterized by an annular elastomeric seal.
By use of the protective cover assembly, a method is provided for preventing overpressure in a fluid end of a plunger-type pump which comprises the steps of providing an open end in the fluid end of the pump in communication with at least one cylinder of the pump, sealingly blocking the open end with a protective cover having a buckling disc portion, determining a maximum load on the buckling disc portion whereby the buckling disc portion buckles in response to a predetermined pressure level in the pump, and retaining the cover in the open end. The step of determining a maximum load on the buckling disc portion may comprise selecting an enlarged thickness of at least a portion of the buckling disc portion. Additional steps comprise positioning sensing means adjacent the buckling disc portion for sensing buckling thereof and interrupting power to the pump in response to the sensing of the buckling. The method may further comprise containing the reverse buckling disc portion and dissipating the kinetic energy thereof in the event of rupture of the buckling disc portion.
An important object of the present invention is to provide a protective cover assembly having buckling relief means therein for buckling in response to the overpressure in a plunger-type pump or other positive displacement pump, the buckling thereby relieving the overpressure in the pump without venting fluid externally thereof.
An additional object of the invention is to provide a protective cover assembly with a cover having a domed center portion with a convex surface generally facing a plunger of the pump and adapted for buckling away from the plunger in response to a predetermined pressure in the fluid end of the pump.
A further object of the invention is to provide a cover having a domed center portion with an enlarged section for affecting a pressure level required for buckling the domed portion.
Still another object of the invention is to provide a method of preventing overpressure in the fluid end of a plunger-type pump without venting fluid from the pump.
Additional objects and advantages of the invention will become apparent as the following detailed description of the preferred embodiments is read in conjunction with the drawings which illustrate such preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a horizontal section elevation of a portion of the fluid end of a plunger type pump employing a prior art protective cover assembly.
FIG. 2 is a view similar to FIG. 1, but illustrating the protective cover assembly of the present invention with a first embodiment of a reverse buckling disc.
FIG. 3 is a view similar to FIG. 1 and illustrating an alternate embodiment of a reverse buckling disc.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and more particularly to FIG. 1, a prior art type of protective cover assembly for positive displacement pumps is shown, and generally designated by the numeral 10. Prior art cover assembly 10 is substantially the same as that disclosed in U.S. Pat. No. 4,520,837 to Cole et al., assigned to the assignee of the present invention.
Cover assembly 10 includes a shallow cup-shaped cover 12 having a cylindrical outer portion 14 and a circular inner shear disc 16 with an arcuate boundary 18 of reduced wall thickness therebetween. Outer portion 14 includes an outwardly extending annular flange 20.
Cover 12 fits into open, outer end 22 of a cylinder 24 of fluid end 26 of a pump. The pump typically has a plurality of cylinders, such as the HT-400 Horizontal Triplex Pump manufactured by Halliburton Services of Duncan, Okla. There is one such cover 12 at the outer end of each cylinder 28 in the pump. In the operating position of cover 12 shown in FIG. 1, flange 20 extends into annular fluid end recess 28 adjacent outer end 22 of cylinder 24. Flange 20 is of greater diameter than outer end 22 but less than that of fluid end recess 28. An elastomeric seal 30 is disposed between cover 12 and outer end 22 and adjacent flange 20 and recess 28.
Cover 12 is positioned substantially coaxially with pump plunger 32 in cylinder 24. As shown in FIG. 1, installed at the bottom of cylinder 24 is an inlet or suction valve assembly 34, including inlet valve 36 which is biased by a spring 38 against a valve seat 40. At the top of cylinder 24 is an outlet or discharge valve assembly 42, including an outlet valve 44 which is biased by a spring 46 against a valve seat 48. In normal pump operation, fluid enters cylinder 24 through suction valve assembly 34 by the withdrawal of plunger 32 from cylinder 24, after which the fluid in cylinder 24 is raised in pressure by the advance of plunger 32 toward cover 12 in cylinder 24, the fluid then exiting from cylinder 24 into outlet passage 50 through discharge valve assembly 42. As this type of plunger pump and its operation are well known in the art, no further explanation will be given thereof, nor of the drive means for plunger 32, such drive means being also well known in the art.
The inner end of cover 12 which generally faces plunger 32 has a flat circular end face 52 surrounded by an oblique annular face 54. The opposite side of cover 12 includes a shallow cone portion 56 which extends away from cylinder 24.
Cover 12 is maintained in fluid end 26 by the insertion of cup-shaped one-piece cover retainer 58 into fluid end 26 and the making up of threads 60 on cover retainer 58 to threads 62 in fluid end 26 adjacent fluid end recess 28. Thus, flange 20 on cover 12 is clamped between cover retainer 58 and fluid end 26, with elastomeric seal 30 providing a fluid-tight seal between cover 12 and fluid end 26.
Cover retainer 58 further includes hammer lugs 64 on its exterior, by which the cover retainer may be tightly threaded to fluid end 26 by a sledgehammer, as is commonly used in petroleum industry field operations.
The interior of cover retainer 58 is of substantially frustoconical configuration, being defined by two contiguous frustoconical inner walls 66 and 68. Wall 66 has a greater angular taper than wall 68. A flat end portion or "bottom" 70 is located at the outermost end of conical wall 66 and generally faces cover 12. At least one aperture 72 extends from the exterior of cover retainer 58 to the interior thereof.
When the pressure in cylinder 24 exerts a force exceeding the design shear load of arcuate boundary 18 of cover 12, shear disc 16 is sheared from outer portion 14 and is propelled outwardly toward cover retainer 58.
Inner wall 68 is of greater inner diameter throughout its length than the diameter of shear disc 16 (as defined by the diameter of arcuate boundary 18) and therefore will not substantially interfere with the movement of shear disc 16, even if the shearing along arcuate boundary 18 is eccentric and movement of shear disc 16 is not entirely coaxial. However, at line 74 where conical wall 66 begins, the diameters of conical wall 66 and shear disc 16 are substantially the same. Thereafter, the diameter of conical wall 66 rapidly reduces so that the periphery of sheared shear disc 16 will contact inner wall 66 and will plastically deform as it progresses to the end of inner wall 66 at bottom 70 of cover retainer 58 whereby the kinetic energy of shear disc 16 is safely dissipated. Aperture 72 in cover retainer 58 permits safe venting of the pump pressure to the atmosphere by redirecting the pressurized fluid outwardly.
In order to prepare fluid end 26 of the pump for service after an overpressure, each cover retainer 58 which has vented is backed off from fluid end 26, and both shear disc 16 and outer portion 14 of protective cover 12 are discarded. A new, unsheared cover 12 is easily installed as already described.
If the overpressure in cylinder 24 is caused by sandout, the shearing of shear disc 16 may be eccentric, and the shear disc may not strike conical inner wall 66 of cover retainer 58 squarely. However, the force will still be transmitted to conical inner wall 66, and may in fact be less than in an instance of uniform shear, as part of the pressure may be vented to the atmosphere as shear disc 16 shears rather than acting to propel the shear disc outwardly.
While prior art cover assembly 10 has worked well in many situations, there are problems associated therewith which can cause premature shearing. One such problem is low fatigue life because cover 12 cycles alternately in compression and tension as plunger 32 reciprocates in fluid end 26. This cyclic stress causes fatigue along arcuate boundary 18 and may result in premature shearing of shear disc 16, even at low pressures. The thickness of cover 12 along arcuate boundary 18 must be thin so that shear disc 16 shears as desired, and this does not allow much corrosion allowance. Further, cover 12 must be machined to its final shape, and this machining leaves machine marks which act as stress risers, thus increasing the stresses adjacent arcuate boundary 18 and adding to the fatigue problem.
Another problem with prior art cover assembly 10 is that venting fluid externally of the pump is not particularly desirable.
Referring now to FIG. 2, the protective cover assembly of the present invention is shown and generally designated by the numeral 100, installed in fluid end 26 of a pump. As will be seen, the design of protective cover assembly 100 eliminates all of the problems associated with prior art cover assembly 10. Fluid end 26 as used with the present invention is substantially identical to that used with prior art cover assembly 12 and includes cylinder 24, plunger 32, suction valve assembly 34, discharge valve assembly 42, and outlet passage 50 as hereinbefore described.
As shown in FIG. 2, protective cover assembly 100 includes a cover 102 having a convex or domed center portion 104 with an outer portion including an annular flange 106 extending outwardly therefrom. Annular flange 106 extends into fluid end recess 28 and is of greater diameter than outer end 22 but less than that of fluid end recess 28. A sealing means such as elastomeric seal 108 is disposed between cover 102 and outer end 22 and adjacent flange 106 and recess 28.
Domed portion 104 is of substantially constant thickness and has a convex surface 110 which generally faces plunger 32. Cover 102 is held in place by cover retainer 58 by the engagement of threads 60 on the cover retainer with threads 62 in fluid end 26 adjacent recess 28. Cover retainer 58 thus acts as a retainer means for retaining cover 102 in place in its operating position in substantially the same manner as cover retainer 58 holds cover 12 in place in the prior art apparatus already described. Cover retainer 58 is again tightened by hammering on lugs 64.
Domed portion 104 of cover 102 may be described as a reverse buckling disc 104. The term "reverse" denotes that convex surface 110 is exposed to fluid pressure in cylinder 24. Preferably, convex surface 110 is substantially hemispherical, the sphere, of course, being the strongest geometrical shape, although other convex curvilinear surfaces are also suitable. The term "buckling" implies that disc 104 is designed to fail by buckling rather than by shear. In other words, when the pressure in cylinder 24 exceeds the design load of reverse buckling disc 104, the disc acts as a buckling relief means, preferably buckling outwardly away from plunger 32, thus relieving the pressure. In this way, fluid is not normally vented from fluid end 26 upon overpressure. However, if the pressure is sufficiently high to rupture reverse buckling disc 104 or tear it away from flange 106, cover retainer 58 will catch and contain disc 104 in a manner similar to that described for the prior art apparatus. When this occurs, the kinetic energy due to the movement of disc 104 is dissipated by contact of the disc with conical inner walls 68 and 66. Fluid pressure is vented through aperture 72.
It will be seen by those skilled in the art that reverse buckling disc 104 is always in compression during reciprocation of plunger 32 in fluid end 26. Thus, the present invention has a greatly improved fatigue life over the prior art apparatus because of the absence of great cyclic stress. Further, the essentially constant thickness of reverse buckling disc 104, compared to the thin section of arcuate boundary 18 around shear disc 16 of cover 12 in the prior art device, gives added corrosion life.
The manufacturing problems associated with the prior art apparatus are also eliminated. The spherical shape of reverse buckling disc 104 of the preferred embodiment is easily formed by pressing a plate between a ball and die. In this way, no machine marks are present which again improves fatigue life. Even if reverse buckling disc 104 is not spherical, but of some other convex curvilinear configuration, it is also easily formed by a similar stamping process with no machining marks.
In addition, convex surface 110 should also help minimize turbulence during pumping, keeping the proppant suspended by providing streamlined flow paths around the surface of reverse buckling disc 104.
As an alternate feature, sensing means such as an electrical sensor or contact strip 112 can be attached to concave surface 114 of reverse buckling disc 104 and placed in electrical communication with the transmission or power source on the pump. When buckling disc 104 buckles due to overpressure in cylinder 24, the electrical connection is interrupted or an electrical signal is sent which can shift the transmission to neutral or shut down the power source, thus protecting the pump as well as the reverse buckling discs 104 in the other cylinders of the pump.
Referring now to FIG. 3, an alternate embodiment of the protective cover assembly of the present invention is shown and generally designated by the numeral 200. Alternate cover assembly 200 includes a cover 202 with a convex or domed center portion 204, also referred to as reverse buckling disc 204, and having an outer portion including an annular flange 206 extending outwardly therefrom. Cover 202 is assembled with seal 108 and held in place by cover retainer 58 in a manner substantially identical to the first embodiment.
Reverse buckling disc 204 has a convex surface 206, again preferably hemispherical in configuration, which generally faces plunger 32. However, reverse buckling disc 204 is not of constant thickness. Instead, concave surface 208 of reverse buckling disc 204 is truncated by a substantially flat transverse surface 210, resulting in an enlarged center section 212 at approximately the center of reverse buckling disc 204. By selectively varying this thickness, the pressure in cylinder 24 required to buckle reverse buckling disc 204 may be varied. Thus, means are provided for selectively varying the failure pressure of the reverse buckling disc.
As with the first embodiment, a sensing means, such as electrical sensor or contact strip 214 may be attached to reverse buckling disc 204, for example, along flat surface 210, for sensing buckling and interrupting power to the pump in response to the buckling.
In addition to providing an enlarged section on the reverse buckling disc, other means of selectively varying the failure pressure include varying the strength of the material from which reverse buckling disc 102 or 202 is formed. Also, the wall thickness in reverse buckling disc 102 or 202 may be varied as desired to provide failure at the desired predetermined pressure in cylinder 24.
It can be seen, therefore, that the protective cover assembly with reverse buckling disc of the present invention is well adapted to carry out the ends and advantages mentioned as well as those inherent therein. While numerous changes in the construction and arrangement of parts may be made by those skilled in the art, all such changes are encompassed within the scope and spirit of the appended claims. | A protective cover assembly for a fluid end of a plunger-type pump or other positive displacement pump. The protective cover assembly includes a cover adapted to fit in an open end of the fluid end of the pump. The cover comprises a convex or domed center portion adapted for buckling away from a plunger of the pump when pressure in the pump exceeds a predetermined level and further comprises an outer portion. A cover retainer is engageable with the open end of the fluid end of the pump and is adapted for clamping the outer portion of the cover to the fluid end. A seal is provided between the outer portion of the cover and the fluid end. The convex center portion of the cover has a convex surface generally facing the plunger, and the convex surface is preferably hemispherical. In one embodiment, the convex center portion has a substantially constant cross-sectional thickness, and in an alternate embodiment, the convex center portion has an enlarged section adapted for affecting a pressure level required for buckling the convex portion. A method of preventing overpressure in a fluid end of a plunger-type pump using the protective cover assembly is also disclosed. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a machine tool which automatically carry out rebel shifts of stator winding of an AC machine.
2. Disclosure of the Prior Arts
It has been well-known that the stator winding of a large size synchronous machine is prepared by twisting many component wires (insulated rectangular type wires) as rebel shifting, in order to prevent a loss caused by eddy current. In many cases, the shape of the stator winding is in a diamond coil shape and the insulated diamond coil is put in each open slot of the stator.
It has been usual to rebel-shift a bundle of component wires by a hand operation or by using a machine tool for twisting component wires by turning slowly a disc holding a drum of the component wires while taking out the component wires.
In the latter case using the machine tool, the stepping of the component wires is carried out for each pitch by pressing the component wires.
Referring to the drawings, the conventional stepping operation will be illustrated.
In the drawings, the same references designate identical or corresponding parts and a hatch for a sectional view is eliminated so as to be easily understood in certain drawings.
FIG. 1 shows a bundle of component wires treated by the rebel shifting and FIG. 1(a) is a sectional view perpendicular to the component wires and FIG. 1(b) is a sectional view parallel to the component wires. The reference numeral (100) designates a bundle of component wires which are arranged in two rows extending in a row direction and several lines extending in a line direction; (200) designates an insulator between two rows and (300) designates an insulator for a shifted wire (hereinafter referring to a S-insulator). As shown in FIG. 1(b), the component wire of the bundle (100) is shifted from the lower row to the upper row and the other component wire is shifted from the upper row to the lower row (the latter is not shown in FIG. 1(b)). The shifting point of the adjacent component wire is departed for one pitch shown as P in FIG. 1(b). The component wire is also shifted in the lines at the shifting point for the row whereby the component wires of the bundle are alternatively shifted.
In order to prepare such structure of the bundle of component wires by a hand operation, it is necessary to carry out the stepping of the component wires first.
FIG. 2 is a side view of a part of the stepped component wires. The stepped height W is equal to the sum of the width of the component wire and an insulator (200) between the rows and the distance between the shifting points of the adjacent component wires is one pitch P which is usually 50 mm to 100 mm.
When number of the lines of the component wires is N, and the stepped-bending of the component wires is carried out the component wire shifted is returned to the original condition at the distance departed for NP from the shifted point. Thus, the shaped component wires for one row are disposed on a table so that the edges are upper and the central parts are lower. The edge of the component wire which has the longest non-contacting portions, is lifted up and is crossed over the other bent component wires and is put on the opposite side. Then, the adjacent component wire is moved in the same manner in sequence. After finishing edges of the component wires in one side, the edges of the component wires in the other side are moved in the same manner from the longest non-contacted component wire in sequence.
In the operation, the non-contacted parts which should be lifted are sometimes about 4 m and the component wires are thin and easily bent. Accordingly, sometimes, it is necessary to lift up the component wire by three to four persons. The hand operation is simple but requires the labour work by many persons.
The other component wires in the other row are combined in the same manner. The former grouped component wires are turned over to cover on the latter grouped component wires and the edges of non-contacted parts of the latter grouped component wires are shifted on the contacted portion of the component wires. The other edges of the grouped component wires are also shifted in the same manner. The insulator between the rows (200) is inserted after the shifting operation. The hand operation is quite complicated as described. Moreover, in the operation, it is necessary to treat the component wires by stepped bending. The component wires for each row are previously combined and then, the two grouped component wires for two rows are further combined. Accordingly, it is evident for a hand operation that the rebel shifting can be attained only for a simple half coil prepared by carrying out the stepped combination for straight portions of the component wires and then bending the coil ends to curve them. Thus, the curved bundle of component wires or the bundle of component wires whose one ends are fixed such as one turn full coil or the coil ends could not be treated by the rebel shifting.
The half coil is prepared by cutting off both of noses of the diamond coil.
The one turn full coil is prepared by cutting off one end of the nose of the diamond coil. The rebel shifting is performed in the slot part.
The coil end means the part having relatively slight curve from the straight part of the slot part to the nose part.
The conventional machine disposing many drums of the component wires on a disc table has been used for a small number of the component wires in one bundle.
When the number of the component wires are 40 to 150 as a stator coil of a rotary machine, the number of the drums of the component wires is great. Accordingly, such machine has not been used in the fields of coils of rotary machines.
The disadvantages of the conventional methods are as follows.
(a) it is operation requiring many steps and greater labour costs
(b) the stepped combination could be attained only for straight component wires; and
(c) it is necessary to combine an insulator between rows.
The operation for inserting the insulator for shifted wire (6) is carried out after the stepping operation. That is, the component wires are bent and shifted, a spatula having a thin edge of a width of 10 mm and a thickness of 5 mm is inserted into a gap under the component wire (10) which has been bent and shifted and an insulator for shifted wire (6) having a predetermined size is inserted into the space. The insulator for shifted wire (6) is a sheet having a thickness of 0.1 to 0.2 mm on which mica is bonded.
It takes about 10 second to shift one part and accordingly, it takes about 30 to 60 minutes for one coil.
Thus, the stepped combination is a simple work but it requires a long labour time and many persons to be low productivity, disadvantageously.
SUMMARY OF THE INVENTION
It is an object of the present invention to overcome the above-mentioned disadvantages and to provide an apparatus for automatically carrying out the stepped combination without a hand operation to improve the productivity and to reduce the labour work.
It is another object of the present invention to provide an apparatus which overcomes a complicated hand operation and provides advantages that rebel shiftings can be applied to a coil end or a straight part of a one turn full coil because the bendings of component wires for fixing one end or one part of a bundle of component wires can be applied before a stepped combination.
It is the other object of the present invention to provide an apparatus for continuously preparing U-shaped bundle of component wire by a shuttle winding in rebel shifting for a one turn full coil.
It is the other object of the present invention to prevent assembly during or after a stepped combination since an insulator between rows and a thin pipe for cooling can be arranged before the stepped combination.
In accordance with the apparatus of the present invention, a wide floor area is not required and the rebel shifting and the insertion of an insulator for shifted wire can be easily attained for a short time by a simple apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows windings formed by a rebel shifting; and FIG. 1(a) is a sectional view perpendicular to the component wires and FIG. 1(b) is a sectional view parallel to the component wires;
FIG. 2 is a side view of stepped component wires;
FIG. 3 is a schematic view of an important part of one embodiment of the apparatus of the present invention;
FIGS. 4, 5, 6, 7, 8 and 9 respectively show the operations according to the present invention; and FIGS. 4(a), 6(a) and 7(a) are respectively front views thereof; and FIGS. 4(b), 4(c) FIGS. 5(a), 5(b), FIGS. 6(b), 6(c), FIGS. 7(b), 7(c) and FIGS. 8(a), 8(b) are respectively side views thereof; and FIG. 9 is a plan view;
FIG. 10 is a sectional view of a thin metal tube for passing air;
FIG. 11 is a schematic view of the other embodiment of the present invention;
FIGS. 12(a) through 12(d) shows detail of rollers;
FIGS. 13(a) through 13(e) shows steps for stepped combinations;
FIGS. 14 and 15 are respectively a side view and a plan view of the other embodiment of the present invention;
FIGS. 16 and 17 respectively show presses and dies used for bending in the present invention;
FIGS. 18(a), 18(b) are a side view and a front view of an apparatus for clamping insulators under a shifted wire;
FIGS. 19(a), 19(b), 19(c) are respectively a plan view, a side view and a front view for showing a transferring device for transferring a bundle of component wires and a knife device for cutting a lower part of the insulator under a shifted wire;
FIGS. 20(a) through 20(o) are sectional views and side views for illustrating steps given by the apparatus of the present invention; and
FIGS. 21(a) through 21(d) are sectional views for illustrating a component wire recycling device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 is a schematic view of the important part of one embodiment of the apparatus of the present invention. In FIG. 3, the extended parts of the component wires (100) in the directions of X, X' and Y, Y' are not shown and can be a cut edge or the edges in X and X' directions can be connected through a nose. The shape of connecting the edges is called a one turn full coil shape.
In FIG. 3, the references (1a), (1b) form a component wire bending device. In the embodiment of FIG. 3, the bending device has a press mechanism having the upper mold (1a) and the lower mold (1b). The bending device can include other mechanisms such as a roller mechanism and a lever mechanism beside the press mechanism.
The reference (2a) designates a knife device for separating a component wire for stepped combination from the adjacent component wire; (2b) designates a push rod which pushes the component wires for stepped combination to shift one step; (2c) designates a hook device for changing the row of the component wire for stepped combination.
The apparatus of the present invention has a structure comprising a position shifting device and a drive controlling device (not shown) wherein the position shifting device fits and transfers the bundle of component wires (100) to a predetermined position depending upon the predetermined program and shifts the parts for stepped combination in sequence to the position shown in FIG. 3 and transfers the bundle of component wire (100) for one pitch P to X, X' direction after each stepped combination of said part, and carrying out the next stepped combination at the position departed for one pitch P; and the drive controlling device drives the knife device (2a), the push rod (2b), the hook device (2c) and the component wire bending device (1a, 1b) depending upon a predetermined program.
These devices are not shown in FIG. 3 since a design of these devices are well-known by a person skilled in the art. (One embodiment of these devices is shown in FIG. 19.)
The operation of the apparatus of the present invention will be illustrated.
For example, a preparation of the component wires in the first step in the case of a manufacture of a diamond coil, is carried out in the separate place, by a hand operation or a shuttle winding operation.
In the shuttle winding operation, a length of a spool is about 1/2 of the expanded wire of the diamond coil and a width of the spool is the same with the inner diameter of the nose of the coil and a width of the groove of the spool is two times of the width of the component wire. Two component wires are wound on the spool in parallel for number of thurns corresponding to the required stepped combinations. Then, the spool is disassembled to remove the bundle of component wires and the bundle is bound by a string if necessary to prevent a break of the bundle. A center of the nose at one side is cut by a large clipper and the curved portions are straighten by a wooden hammer.
Usually the rebel shifting is performed only at the slot part of the diamond coil and accordingly, each insulator (200) is inserted into each row at the slot parts. The insulator (200) can be a polyamide resin sheet (5 mils) such as Normex 411 (manufactured by Du Pont).
The operation of the apparatus of the present invention will be illustrated referring to FIGS. 4, 5, 6, 7, 8 and 9 wherein FIGS. 4(a), 6(a) and 7(a) are respectively front views; FIGS. 4(b), 4(c), 5(a), 5(b), 6(b), 6(c), 7(b), 7(c) and 8(a), 8(b) are respectively side views and FIG. 9 is a plan view.
In the step of transferring the bundle of the component wires (100), the relation of the component wires (100) and the devices (1a), (1b), (2a), (2b) and (2c) are shown in FIG. 4. FIG. 4(b) is a side view taken from the A--A' plane of FIG. 4(a) in the arrow direction; FIG. 4(c) is a side view taken from the B--B' plane of FIG. 4(a) in the arrow direction.
In FIG. 4(c), the reference numbers (3) to (14) are given for the component wires (100) and the stepped combination is given for the component wire (8) and the component wire (14). The component wire (8) is shifted to the lower row and the component wire (14) is shifted to the upper row. The shifting is carried out in the following order. The component wire is referred to as a wire. As shown in FIG. 5(a), the knife devices (2a) are respectively inserted between the wires (8), (7) and between the wires (14), (13) whereby the wires (8), (14) are free to shift and to be inserted between the press molds of the component wire bending device (1a), (1b) in a precise manner. At this time, the hook devices (2c) are pushed to the center by springs whereby the hook devices are outwardly shifted and prevent the falling of the wires (8), (14).
Then, the push rods (2b) are pulled as shown in FIG. 5(b). The bundle of the component wires (100) is held by the knife device (2a) to prevent breaking.
In the next step, the wires are pressed by the component wire bending device (1a, 1b) to form a step as shown in FIGS. 6(a), 6(b) and simultaneously, the wires stepped by the pressing are respectively shifted (the wire (8) is downwardly shifted and the wire (14) is upwardly shifted).
In the returning step shown in FIGS. 7(a), 7(b), 7(c), the push rods (2b) are returned to push the wires (8), (14) while hook devices (2a) are returned and the press molds (1a, 1b) are vertically returned and the knife devices (2a) are pulled out.
In the next step shown in FIGS. 8 and 9, the pushing force of the push rods (2b) is increased to push the wires (8), (14) into the row whereby the wires (13), (7) are pushed out. The stepped combination for one pitch is finished. The condition is now returned to the condition shown in FIGS. 4(a), 4(b), 4(c) except the wire (7) is shifted to the position of the wire (8) and the wire (13) is shifted to the position of the wire (14).
The bundle of the component wires (100) is transferred for one pitch and the next stepped combination is carried out.
As it is clearly understood by the above-mentioned description, it is unnecessary to form a stepped shape before the bounding of the component wires as the conventional method.
In the present invention, the bundle of component wires are previously prepared and one end of the bundle is fixed and then, the stepped combination can be carried out in sequence from the other end. Thus, the following preparation can be attained.
The conventional stepped combinations are applied on the straight part of a half coil, and then, the end of the straight part is bent and then, the stepped combinations of the coil end part are applied from the end of the straight part to the coil end in sequence by the apparatus of the present invention. Of course, the stepped combinations at the slot part as the half coil can be carried out in the straight part of the bundle of component wires.
In the embodiment of the present invention, the insulator is inserted between the rows of the wires. Thus, it is also possible to insert the insulator after the stepped combinations without inserting each step. In the case of a large size coil, a thin metal tube for air cooling is arranged in the row of the component wires and the stepped combinations are carried out, whereby the bundle of component wires incorporating the tube (400) in the rows shown in FIG. 10 can be obtained.
In FIG. 11, the reference numerals (1-1), (1-2) designate rollers which are disposed as pairs at both sides of the bundle of component wires (30) of a formerly wound coil and in each interval of 30 to 50 cm in the longitudinal direction of the bundle (30). The reference numeral (2) designates a press type or lever type stepping mechanism for bending the wire (10) to form the stepped shape and (3) designates a transferring mechanism to transfer the bundle of component wires (100) to the arrow direction each time one step operation is finished, to the position under the stepping mechanism (2) for the next stepping operation. The stepped combination device is formed with the rollers (1-1), (1-2), the stepping mechanism (2) and the transferring mechanism (3).
The rollers (1-1), (1-2) will be illustrated in detail.
The rollers (1-1), (1-2) are the same as each other.
Referring to FIG. 12, the roller (1-1) is illustrated. FIG. 12(a) is a plan view; FIG. 12(b) is a front view and FIG. 12(c) is a right side view; (4--4) is an expansion view for showing the shape of the surface of the roller (1-1).
On the surface of the roller (1-1), a groove having a width larger slightly than the width of one component wire (10) is formed so as to shift the component wire (10) for a length of the sectional view of the component wire (10) in the longitudinal direction during one turn of the roller (1-1) (between a to b in one turn). There is no groove in the part c . The distance from the center of the roller (1-1) is an average of the distance from the center to the bottom of the groove and the distance from the center to the surface of the roller (1-1) having no groove (between a and b ).
The groove is smoothly changed from c to a and b to c .
The rollers (1-1), (1-2) having said structure are turned in the predetermined relation to the stepping mechanism (2) and the transferring mechanism (3).
The operation will be illustrated. The component wires are arranged in two rows between the rollers (1-1), (1-2) under the condition that the wire are contacted with the non-groove parts of the rollers (1-1), (1-2) (the part c in FIG. 12) and the stepped condition (5-1) in FIG. 13.
In the arrangement, the rollers (1-1), (1-2) are turned to the arrow direction shown in FIG. 13(a), whereby the wires (10) in the upper row are shifted to right and the wire (10) in the lower row are shifted to left whereby each wire is put in each groove of the rollers (1-1), (1-2) as the step of FIG. 13(b). Then, each wire in each groove is transferred by turning the rollers (1-1), (1-2). The wire (10) No. 12 in the right roller (1-2) of FIG. 13(b) is shifted downwardly whereas the wire (10) No. 15 in the left roller (1-1) is shifted upwardly. This corresponds to the steps FIGS. 13(c) through 13(e).
The stepping mechanism is simultaneously operated together with the operation whereby the wires (10) No. 12 and No. 15 are bent and then, the transferring device (3) is operated to transfer the bundle of component wires (30) so as to conform the position for stepping to the stepping mechanism (2). Then, the wires are shifted and they are returned to the first step of FIG. 13(a).
The operations are shown in Table 1 wherein the symbol * designates the structure shown in FIG. 11; ** designates the position contacting the rollers with the component wires (the surface in FIG. 12); and *** designates the step shown in FIG. 13.
TABLE 1______________________________________ Functional part in operation (element) *Stepping *Transfer-Step *Roller mech. ring mech.______________________________________1. Shifting to step o ** direction b○→○a a○→○b ***FIGS. 13(e) 13(a) 13(b)2. Shifting to row o ** direction a○→○b Stepped bending b○→○a o ***FIGS. 13(c) 13(d)3. Transferring to ** wire direction ○b ○a o ***FIG. 13(a)______________________________________
In the embodiment, the rollers (1-1), (1-2) are arranged so that the grooves are in a horizontal direction as shown in FIG. 14. Thus, the rollers can be arranged in slant. In this case, the grooves of the rollers (1-1), (1-2) are in parallel to the rows of the wires (10) whereby the insulation coating for the wires (10) is not damaged.
The rollers (1-1), (1-2) are not limited to ones having the function for one pitch in one turn and they can be ones having the function for one pitch in one of several turn as shown in FIG. 15.
Referring to FIGS. 16 and 17, the die (21) and the press (22) of the stepping mechanism (20) for stepped-bending the wire (10) will be illustrated in detail.
Grooves 21a), (22a) are formed on the die (21) and the press (22) so as to carry out the stepped-bending of the wire (10) under the condition of contacting short sides of the wires in the sectional view.
The parts f , g are in the shape of the knife edge and the part e is a groove having a depth of about 0.5 mm.
Referring to FIGS. 18(a), 18(b) as the side view and the front view, the insulator inserting device (30) which inserts an insulator (6) under a shift wire (S-insulator) during the shifting step will be illustrated.
The S-insulator (6) is cut in suitable width and it is wound on a coiler (31). Rollers (32) intermittently turn to transfer the S-insulator (6) to the arrow direction and a guide (33) leads the S-insulator (6) to a predetermined position.
Referring to FIGS. 19(a), 19(b), 19(c), a trasnferring device (40) for transferring the bundle of component wires (100) for one pitch and the knife device (50) for cutting the lower part of the S-insulator (6) will be illustrated.
The transferring device (40) is disposed on both sides of the bundle of component wires (100) and supporting rods (41) can be shifted in the transversal direction and a shoe (42) is connected on the supporting rods (41) by pins (43).
When the supporting rods are shifted to right in FIG. 19, the shoe (42) is shifted to the arrow direction whereby the shoe (42) slides on the bundle of component wires (100). Thus, when the rods are shifted to left, the shoe (42) is crotched to the bundle of component wires (100) by applying the force to the reverse direction to the arrow direction in the relation of the pin (43) whereby the bundle of component wires (100) is shifted to left.
The knife device (50) is disposed at both sides of the lower surface of the bundle of component wires (100) and the knife device (50) is mounted on the rods (41) and is shifted with the rods (41) in the transversal direction.
The knife edge is disposed so as to contact with the part of the S-insulator (6) contacting with the bundle of component wires (100) whereby the S-insulator (6) is cut during the shifting step when the knife device is shifted to right.
The total operation will be further illustrated wherein the operations of the mechanisms are illustrated referring to FIGS. 20(A), (B) and the relation of rollers (1-1), (1-2) and the wires (10) of the bundle of component wire (100) at the roller part will be illustrated referring to FIG. 21.
In FIGS. 20 and 21, the symbols #1 to #6 designate step numbers. In FIGS. 20(A), (B), the figures (a) are front views and the figures (b) are plan views and the figures (c) are sectional views in the steps.
FIGS. 21(a) through 21(d) are sectional views of the bundle of component wires (100) showing the relations of the wire (10) and the rollers (1-1), (1-2).
In FIGS. 20 and 21, the positions of the wires (10) are defined by numbers of the wires.
The steps will be illustrated.
The wires (10) are arranged in two rows and the S-insulator (6) is inserted between the rows before insulating the bundle of component wires on the apparatus.
The insulator (6) is a polyamide sheet (5 mil) and the width of the insulator is slightly narrower than the width of the bundle of component wires (100).
The rollers (1-1), (1-2) ae turned to the position a of FIG. 12. In this condition, the wires (10) #11 and #14 are pushed by the rollers (1-1), (1-2) whereby the wires (10) #15 and #12 are respectively put in the grooves (21a), (22a) of the rollers. The dies (1a) near the middle part between the rows (Step I).
Then, the dies (1a) push the wires (10) #11 and #14 of the bundle of component wires (100) whereby the wires (10) #12 and #15 are respectively put out to the opposite sides (Step II).
Then, the rollers (1-1), (1-2) are turned to shift upwardly the wire #12 and to shift downwardly the wire #15. The grooves (21a), (22a) of the rollers (1-1), (1-2) have slightly deeper depth after the point b , whereby the wires (10) are vertically shiftable. The dies (1a) and the presses (1b) are shifted so as to nip the wires #12 and #15. The edges f and g of the presses (1b) and the dies (1a) are inserted into the boundaries of the wires to enlarge the gaps and the positions of the wires #12 and #15 are slightly shifted as shown in the plan view (b) (#3).
When the presses (1b) and the dies (1b) are pressed to finish the stepped-bending of the wires #12 and #15 to give desired shapes, the rollers (1-1), (1-2) are stopped at the position c . (Step 3 I).
The rollers (32), (32) are turned to transfer the insulator (6) during the shifting and the S-insulator (6) is lead by the guide (33) to the gap between the wires #13, #14 and the presses (1b) and the dies (1a), that is the grooves e formed on the presses (1b) and the dies (1a). When the S-insulator (6) reaches the upper part of the bundle of component wires (100), the rollers (32) (32) are stopped to stop the S-insulator (6). (Step II).
Then, the presses (1b) and the dies (1a) are returned to the oroginal positions. (Step 4).
The rollers (1-1), (1-2) are turned to stop at the position d . The wires (10) #12 and #15 at the rollers (1-1), (1-2) are put out from the grooves (21a), (22a). The wires (10) #13 and #16 are in the same level with the wires (10) #13 and #16 because the positions of the surfaces of the rollers (1-1), (1-2) are lower level. Thus, the wire (10) #12 and #15 is compressed to the direction of the bundle of component wires (100) whereby the S-insulator (6) inserted below the wires (10) #12 and #15 are firmly fixed. (Step 5 I).
Then, the knife device (50) is shifted in the transversal direction and the insulator (6) is cut at the projected position below the bundle of component wires (100). The transferring device (40) is moved to right and the shoe (42) moves to the arrow direction by the pin (43) whereby the bundle of component wires (100) is not moved. (Step 5 II).
Then, the transferring device (40) is moved to left and the shoe (42) is pressed to the direction of the wire (10) by the pin (43) whereby the bundle of component wires (100) is moved to left. The movement is stopped at the position moved for one pitch. (Step 6).
The rollers (1-1), (1-2) are turned to the position a and the wires (10) #13 and #16 are put in the grooves (21a), (22a) of the rollers (1-1), (1-2).
The stepped combination for one pitch and the insulator inserting operation are completed.
In said embodiment, the bundle of component wires (100) is prepared by arranging the wires (10) while plying the wires. It is also possible to prepare the bundle of component wires (100) by the other methods. For example, a shuttle winding is prepared as the preparation of a diamond coil and the nose at one end is cut to form U-shape and the bundle in U-shape is installed on the apparatus and the stepping of the straight parts of the bundle can be carried out by the method of the present invention. It is also possible to carry out the stepping of the straight part of the half coil (both noses of the diamond coil are cut) and then, to carry out the bending of the edge of the straight part and then, to carry out the stepping of the coil end (a middle part between a straight part and a nose part).
In said embodiment, the S-insulator (6) is fed from a roll. However, it is possible to cut the S-insulator (6) for each one length and to feed automatically each S-insulator (6) to the connecting point.
In said embodiment, the grooves for feeding the S-insulator are (6) at the rear side of the presses (1b) and the dies (1a). However, in order to feed the S-insulator (6) in precise manner, holes for passing the S-insulator (6) can be formed in the presses (1b) and the dies (1a). As the simple method, it is possible to form a space by departing the presses (1b) and the dies (1a) from the bundle of component wires (100) while clamping the wires (10) by the presses (1b) and the dies (1a).
In order to carry out the stepped-bending of the wires (10), the presses (1b) and the dies (1a) are used in said embodiment. However, it is possible to carry out the stepped-bending of the wires (10) by using levers. In said embodiment, the rollers (1-1), (1-2) having the slant grooves (21a), (22a) are used as the device for recycling the wires (10). However, it is possible to use the hooks, the push rods and the knife device.
In said embodiment, the insulator (6) is inserted just after the stepped-bending of the wires. However, it is possible to insert the S-insulator (6) by pushing a spatula between the wires (10) behind several pitches from the stepping mechanism to form each space.
These features are covered by the present invention since the untreated wires (10) of the bundle of component wires (100) are recycled in the stepped-bending operation for one pitch and the S-insulator (6) is inserted for each pitch. | A stepped combination apparatus comprises transferring means for moving a bundle of component wires arranged in plural rows and plural lines in the longitudinal direction; pushing means for pushing the component wires to the line direction to put out a component wire at the opposite side; shifting means for shifting the component wire which is put out by the pushing means, to the other row; and stepped-bending means for stepped-bending the component wire which is put out. The operation time can be significantly shortened and a U-shape bundle of component wires can be treated by the apparatus. | 8 |
.Iadd.Cross Reference of Related Application
This is a continuation of reissue patent application Ser. No. 07/434,888, filed Nov. 13, 1989, now abandoned which is a reissue application for U.S. Pat. No. 4,708,179, issued Nov. 24, 1987 which was filed as Ser. No. 041,418, filed on Apr. 22, 1987. Furthermore, this, .Iaddend. .[.This.]. application .Iadd.Ser. No. 041,115 .Iaddend. is a continuation-in-part of application Ser. No. 818,874 filed Jan. 14, 1986, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to an extendible hose assembly for positioning on a vehicle for servicing portable toilets and the like.
Heretofore it has been customary to wrap a flexible portable hose used in servicing portable toilets around front and rear or like posts, poles or similar mounting arms on the tank of a service vehicle. This has caused numerous problems when attempting to service portable toilets from a service truck. For example, it is time consuming to unwrap and extend the hoses from the truck or like vehicle to the portable toilet, as a long hose has to be wrapped around the mounting arms so that it will reach the toilet when the service vehicle cannot be parked reasonably close thereto. The unwrapping results in the hose falling from the truck and dragging on the ground or through the mud in bad weather in attempting to extend it.
SUMMARY OF THE INVENTION
The present invention is directed to an extendible hose assembly which solves all of the above problems by using at least two hinges to mechanically support the hose assembly and to allow the same to swing in a horizontal plane. A third hinge located at the lower end of the second hinge permits a portion of the assembly to rotate in a vertical plane.
The extendible hose assembly comprises a first elongated, rigid pipe or hose mechanically connected to and extending horizontally from the first hinge to the second hinge and one end of a U-shaped flexible hose; the other end of the flexible hose is connected to one end of a second elongated rigid pipe or hose. The second rigid pipe, in turn, is connected to another flexible section. Hence, all of the hose and pipe portions are serially connected together and in fluid communication with each other.
The first hinge allows the entire hose assembly to swing horizontally, while the second hinge allows the second rigid pipe section to swing horizontally. The third hinge pivotally connects the second rigid pipe portion to the second hinge in a manner that allows the second rigid hose to pivot about the hinge vertically.
The first hinge is shown mounted on the task of a service vehicle, for example, such that a workman can conveniently swing the entire hose combination horizontally away from the tank. This allows the remote end of the last flexible hose of the assembly to be conveniently .[.manuverable.]. .Iadd.maneuverable .Iaddend.and can be easily inserted into the tank of a portable toilet, for example, to pump the contents thereof into the tank of the vehicle.
.Iadd.Additionally, the hinged arrangement of the present invention allows the extendible hose assembly to be folded in substantially "side-by-side" relation longitudinally along the length of the tank to permit transportation of the tank from one site to another.
BRIEF DESCRIPTION OF THE .[.DRAWING.]. .Iadd.DRAWINGS.Iaddend.
For a better understanding of my invention reference will now be made to the .[.drawing.]..Iadd.drawings .Iaddend. which .[.forms.]..Iadd.form .Iaddend.a part hereof and .[.represents .]. .Iadd.represent.Iaddend.a preferred embodiment of the invention.
In the .[.drawing,.]. .Iadd.drawings,.Iaddend.
FIG. 1 is a side elevation of a service vehicle with the extendible hose of the invention in storage or mounted position .Iadd.in vertical "side-by-side" folded relation longitudinally along the tank of the service vehicle. .Iaddend.
FIG. 2 is a perspective view of the service vehicle with the extendible hose in an operative position.
FIG. 3 is an end elevation taken on line 3-3 of FIG. 1.
FIG. 4 is an end elevation taken on line 4-4 of FIG. 1.
FIG. 5 is a perspective view showing a representative rear hinge or pivot construction.
FIG. 6 is a perspective view showing a representative front hinge or pivot construction.
DETAILED DESCRIPTION OF THE INVENTION
Referring now .Iadd.to .Iaddend.the .[.drawing.]. .Iadd.drawings, .Iaddend.FIG. 1 thereof shows in side elevation a tank 12 of a service truck 10, and the extendible hose assembly of the invention, the assembly having six serially connected portions bearing numerals 18, 18', 20, 22, 24, and 54 respectively.
Still referring to FIG. 1, hose 20 is a flexible portion of the hose combination, and extends from an upper portion of tank 12 to a curved, rigid hose or pipe portion 54. Pipe portion 54 is attached to a vertically disposed hinge 14. Hinge 14 is shown mounted on an upper, rear portion of the tank. This is best seen in FIG. 3 of the drawings where hinge 14 is shown as being welded to the tank.
The perspective view of FIG. 5 best shows the attachment of hose portion 54 to hinge 14, and a suitable construction for the hinge. More particularly, the hinge is shown as being comprised of a straight tube or hollow cylindrical member 48 located between the legs of a U-shaped bracket, the legs supporting the ends of the cylinder. The cylinder (48) is .[.rotably.]. .Iadd.rotatably .Iaddend. secured in place between the legs of a bolt 50, extending through the legs and cylinder and a nut 52 threaded on the lower threaded end of the bolt. (Tube 48 and a similar structure 58 are discussed in greater detail below.)
Rigid pipe 54 is shown attached to cylinder 48 of hinge 14 by bars 56 and 56' (FIG. 5) of flat bar stock such that 54 is swingable about the vertical axes of 48 and 50.
Pipe portion 54 curves downward to a lower end of hinge 14 and is shown serially connected to one end of an elongated, rigid, horizontally disposed (FIGS. 1 and 2) pipe or hose 18. Hoses 18 and 54 can be a single piece pipe member, i.e., 18 can be provided with a curved portion (54), as opposed to .[.be.]. being two pieces. A single pipe member is preferred, as it eliminates connecting the two members together and, of course, the physical connection itself.
The other end of pipe 18 is serially connected to one end of U-shaped flexible hose 22, and attached to a second, vertically disposed hinge 16, as best seen in FIG. 6. Again, hinge 16 is comprised of a straight tube or hollow cylindrical structure 58, through which extends a pin 60 in a manner that allows the pin to rotate in the cylinder. A lug 45 is attached to the upper end of the pin. A second pin 62 is suitably attached to the lower end of the pin 60 crosswise and perpendicular thereto. In addition, the end of rigid pipe 18 adjacent cylinder 58 is attached thereto by a relatively short piece of flat stock 66.
The other end of U-shaped flexible hose 22 is serially connected to a second elongated rigid hose or pipe 18'. Adjacent the location of the connection are two supporting lugs 64 .[.suitable.]. .Iadd.suitably.Iaddend.attached to rigid pipe 18', as best seen in FIG. 6, and rotatably supported on pin 62, i.e., pin 62 extends into and between the lugs and in a manner that allows lugs 64 to rotate relative to pins 60 and 62. This provides a third hinge at the lower end of the second hinge.
The other end of rigid pipe 18' is serially connected to one end of an elongated flexible hose 24. The other end of flexible hose 24 has connected thereto a suitable valve 26 and nozzle 28.
.Iadd.To support rigid pipe 18' in its extended position (FIG. 2), a resilient support member comprised of end portions 30 and an intermediate joining spring-like portion 32 is provided. One end portion 30 is secured to lug 45 (as can best be seen in FIG. 6), and the second end portion 30 is secured to the end of rigid pipe 18' which is connected to one end of flexible hose 24. .Iaddend.
Tubes or cylinders 48 and 58 are preferably made from long portions of commercially available, mild steel tube stock. The stock is cut to lengths that will fit into the space between the legs of the U-shaped brackets of hinges 14 and 16. Such tube stock is rigid and can also be used for horizontal pipes 18 and 18'. Further, such stock can be bent to far curved portion 54 at the right hand end (in FIGS. 1 and 2) of pipe 18. In addition, the internal diameters of such tube stock are of a size that can receive commercially available bearing assemblies (bearings and bearing races), which are force fitted into the ends of 48 and 58. This provides hinge assemblies that are easily swingable about their axes.
For storing the combination of hoses, as thus far described, one side of tank 12 is shown provided with brackets 34, 36 and 38. As seen in FIG. 1, nozzle 28 seats in bracket 38, while an intermediate portion of flexible hose 24 rests in bracket 36. Bracket 34 receives the end of rigid pipe 18 that is connected to flexible hose 24.
.Iadd.As can be readily seen in FIGS. 1, 3, and 4 of the drawings, rigid hose sections 18 and 18' are stored the vertical "stacked" side-by-side relation. This "stacked" arrangement is accomplished since the sections 18 and 18' are mounted for horizontal movement in different, respective, horizontal planes as seen in FIG. 2. .Iaddend.
.Iadd.Thus, it can be seen that the rigid pipes and flexible hoses are foldable longitudinally along and snugly against the tank 12. Such folded relation permits the vehicle to be maneuvered through busy streets and other congested areas as it transports the service tank to areas where it may be needed. Such areas may be hard to reach, somewhat inaccessible, wooded areas, as areas under construction. | An extendible hose assembly for extending from a .Iadd.holding tank of a .Iaddend.portable toilet service truck or similar service vehicle to a portable toilet or similar tank to be serviced. The assembly has two rotational hinges for horizontal movement of hoses and at least one hinge allowing vertical movement of hoses. The combination of hinges allows the hoses to be extended for use in any direction from the .Iadd.tank carried by the .Iaddend.service vehicle .Iadd.and to be compactly folded in substantially "side-by-side" relation longitudinally along the length of the holding tank.Iaddend.. | 8 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to improvements in pinch mechanisms. The invention is particularly suited for elastic rebound pinch mechanisms but is not limited thereto.
[0002] Problems exist when moving liquid with conventional pumping methods in which moving parts are exposed to product flow. For example:—
[0003] Gears, seals, pistons and springs in contact with the product flow can very quickly succumb to corrosion, become blocked and or generally become in operative or faulty in operation
[0004] When used in an hygienic environment, or where one pump is used for a variety of liquids, these parts can be difficult to clean without disassembly
[0005] In some cases, peristaltic pumps have been used to try and address these issues, but poor tube life is often cited as a significant limiting factor.
[0006] Elastic rebound pinch mechanisms are known. The mechanisms can function as a valve or as a pump. Generally the mechanism relies on a flexible tube or conduit having elastic rebound characteristics such that the tube can be pinched to close a flow passage through the tube and then released to enable the elastic rebound to restore the tube to substantially its non-deformed state. An elastic rebound pinch mechanism pump of the type disclosed in WO 99/01687 can overcome many of the above identified problems.
[0007] A problem which can arise with pinch mechanisms is that the rebound characteristics of the tube and/or the material from which it is constructed may not be sufficient to restore the tube to its fully non deformed state. Also the speed of movement of the tube to the non-deformed state can be slow. In a pumping situation failure to rebound fully or quickly can impair or at least limit the desired pump characteristics.
[0008] Furthermore the nature of the fluid material to be pumped or moved through the tube may require the tube to be made of a material (or of such thickness) that the elastic rebound characteristics do not permit the tube to rebound to its non-deformed state as fully or as quickly as desired. Alternately the material to flow through the tube may be of a viscosity or be sticky in nature such that once again the desired elastic rebound characteristics of the tube are impaired.
SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to provide an improved pinch mechanism in which the pinch mechanism exhibits favourable restoring characteristics of a deformable tube.
[0010] Broadly in one aspect of the invention there is provided a pinch mechanism including a deformable tube enclosed within a first chamber, the deformable tube defining a flow passage, a second chamber coupled to said first chamber, a piston located within the second chamber, the piston being movable between first and second positions such that upon moving to said first position a pressure increase occurs in said first chamber and upon moving to said second position a negative pressure is established in said first chamber and vent means, which at a point during movement of the piston between the first and second positions enables a pressure equalisation within the second chamber occur.
[0011] According to one form of the invention the deformable tube is resilient and exhibits an inherent rebound characteristic such that the tube tends to revert to a substantially non-deformed state.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 in schematic form illustrates one embodiment of the invention in the form of a rebound pinch mechanism forming part of a pump,
[0013] [0013]FIG. 2 is, in more detailed form, a cross-sectional drawing of a second embodiment of the invention,
[0014] FIGS. 3 to 5 are views of the second embodiment at different operational stages, and
[0015] [0015]FIG. 6 is a more detailed illustration of the valve unit employed in the second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] Referring to FIG. 1 there is shown a flexible tube 10 which is subjected to cyclic compression or pinching of the tube into a closed or partially closed position and released to a substantially non-deformed configuration. The flexible tube 10 is typically a silicone tube.
[0017] According to the invention flexible tube 10 is located within a housing 11 which has a cross sectional shape commensurate with that of the exterior wall surface of tube 10 . Thus in one preferred form of the invention tube 10 is of circular cross section as is the housing 11 . A clearance 12 is provided between the inner wall surface 13 and outer wall surface 14 of the respective housing 11 and tube 10 . For the purposes of illustration FIG. 1 exaggerates the extent of clearance 12 .
[0018] The housing 11 is sealed at each end. In the illustrated form the sealing effect is achieved by the positioning at respective ends an inlet valve 15 and an outlet or exhaust valve 16 . In accordance with normal pinch mechanism technology the exhaust valve 16 opens upon the tube 10 being pinched to a closed position. The exhaust valve 16 closes and the inlet valve 15 opens as the tube 10 reverts to its non-deformed state.
[0019] Because housing 11 is sealed closed at each end the tube 10 is effectively located within a chamber 11 a.
[0020] According to the present invention a mechanical force contacting the tube is not applied in order to achieve the pinching action. By contrast with known pinch mechanisms the pinching action is preferably achieved pneumatically.
[0021] Thus according to the preferred pneumatic form of the invention a port 17 is formed in the wall of the housing 11 . Port 17 communicates via passage 18 with a chamber 19 (more particularly a cylinder) in which a piston 20 can reciprocate. A piston rod 21 extends from the piston 20 . Rod 21 is coupled to an actuating means such as a motor, linear actuator or the like. Seals 22 associated with piston 20 slidingly engage with the inner wall surface 23 of the chamber housing 24 to provide the required sealing effect.
[0022] Associated with the housing 24 is a transfer port 25 .
[0023] As the piston rod 21 moves in the direction of arrow A (see FIG. 1) the piston 20 moves toward transfer passage 18 . Once the seals 22 have moved beyond the transfer port 25 air located between the piston 20 and inside of housing 11 is gradually compressed. The compressed air acts on the tube 10 to thus cause the tube to collapse inwardly.
[0024] In the preferred form of the invention the tube 10 is confined within the encasement of housing 11 therefore tube 10 is confined in the manner disclosed in our patent specification WO099/01687. Thus tube 10 collapses inwardly in an inverted manner into a sealed closed state as illustrated in FIG. 3 of WO99/01687. However, this inverted collapse of the tube is created not by mechanical means as disclosed in WO99/01687 but via the application of pressurised air.
[0025] It has been found that the tube 10 will inwardly invert in the vicinity of port 17 but not necessarily directly adjacent port 17 . The tube will tend to inwardly invert at the point of least resistance to inversion.
[0026] When the piston 20 retracts the pressure dissipates. As the piston 20 crosses the transfer port 25 pressure in the chamber 19 will be equalized to atmospheric pressure. This occurs because chamber 19 vents via port 25 to atmosphere, the reverse side of piston 20 being exposed to atmosphere.
[0027] As the piston retracts further transfer port 25 will close and a negative pressure will develop within the chamber 19 and hence within chamber 11 a in the housing 11 . This negative pressure creates a sucking effect on the tube 10 and causes it to revert to its normal state. Then as the piston rod 21 once again moves in the direction of arrow A the negative pressure is dissipated and equalised to atmospheric pressure as the transfer port 25 is once again opened.
[0028] Such negative pressure applied to the tube 10 can actually cause the tube 10 to expand beyond its normal state. Therefore not only does the application of a negative pressure on the tube aid in it reverting to its non-deformed state it can also further assist the efficiency of the pinch mechanism when used in a pump application.
[0029] The throughput of the pinch mechanism when used in a pump configuration can be adjusted by the speed and/or stroke of piston 20 . Tests to date show that a pump according to the present invention can be kept dimensionally compact. Hence the pump can be more compact than a conventional pinch mechanism pump where the pinching action relies on the application of mechanical force to pinch the tube closed and reliance on the rebound characteristics of the tube for the tube to return to its “open” state.
[0030] The invention is open to modification. For example the piston mechanism can be located remote from the housing and coupled by say a tube between transfer passage 18 and port 17 . This may be advantageous when the pump operates as say an immersion pump.
[0031] The embodiment of the invention shown in FIG. 1 demonstrates some excellent attributes such as:—
[0032] No moving parts in contact with the liquid flow.
[0033] A clear unobstructed product flow providing excelling hygiene properties making cleaning simple.
[0034] The pump occupying a small physical space.
[0035] A wide range of motive power possibilities for the pump including small and large electric motors, battery, air, vacuum, water or hand operation.
[0036] Pump sizing being scalable to provide a wide range of volume capabilities.
[0037] Simple or complex electronics being incorporated to control the pump operation including dispense volumes and times.
[0038] However, when seeking pumping solutions for a wider range of applications some limitations can arise. These can be characterised as follows.
[0039] The pump can in some applications display restrictive lift capabilities due to limitations arising from the tube rebound properties and/or the tensions required for springs etc. in the inlet valve.
[0040] Dependency on tube rebound properties can limit potential applications of the pump in terms of viscous fluids and chemical compatibility.
[0041] Siphoning can still possibly occur through the pump where suction (vacuum) on the outlet is greater than the biasing force used to close the valves.
[0042] One or more of these limitations can be overcome by the pump arrangement which incorporates the invention and is shown in a second embodiment in FIG. 2.
[0043] As with the first embodiment the pump shown in FIG. 2 includes a length of silicone rubber (or equivalent) tube 10 an inlet valve 15 and an exhaust valve 16 . Once again valves 15 and 16 are contained in a pressure tight fit with housing 11 . In accordance with the first embodiment the operative mechanism is a small air cylinder that can generate positive and negative pressures. The cylinder 24 is connected to the housing 11 via port 17 .
[0044] As will hereinafter be described, the inlet valve 15 is positioned within the tube 10 with one or more apertures which is/are actually closed by the tube. The exhaust valve 16 is in the preferred form of the invention identical to the inlet valve 15 except that the aperture(s) is/are located external of the housing 11 .
[0045] [0045]FIGS. 2 and 3 show the pump in the “at rest” state. It will be observed that the piston 20 is located at the transfer port 25 . The chamber 19 and the chamber 11 a in housing 11 are thus both at atmospheric pressure.
[0046] [0046]FIGS. 2 and 6 show a valve body B which with the tube 10 forms each of inlet valve 15 and exhaust valve 16 . The valve body B comprises a tubular body 26 with a bore 26 a . The tubular body 26 is closed at one end by a wall 27 preferably formed integrally with body 26 . A peripheral outwardly projecting rib 28 extends from the body 26 .
[0047] The tubular body 26 is inserted into the tube 10 . In the case of the inlet valve 15 the body 26 is inserted in the tube so that wall 27 thereof is inboard of the end of the tube 10 . The exhaust valve 16 is formed by body 26 inserted so that the end wall 27 is located outside the chamber ila formed in housing 11 .
[0048] As show in FIG. 2 an external screw thread 29 is applied to each end of the housing II. An end cap 30 is coupled to each end of the housing 11 . The end cap 30 has an annular wall 31 with an internal screw thread 32 to facilitate this coupling.
[0049] A concentric opening 33 is formed in the end cap 30 . Extending through this opening 33 is a fitting 34 . This fitting has a peripheral rim 35 at one end so that it engages not only with the underside of the top 36 of the cap 30 but also the tube 10 where the tube extends over the peripheral rib 28 . Thus by screwing on the end cap 30 not only is the fitting 34 attached but also the valve body 26 is located firmly in position so that it cannot move axially relative to the tube 10 . Equally the tube 10 is also anchored into position so that it is held in a correct position within the housing 11 .
[0050] In use appropriate conduits will be coupled to the pump via fittings 34 .
[0051] Located adjacent end wall 27 of each valve body 26 is a plurality of radial ports 37 .
[0052] The tube 10 where it fits over valve body 26 thus actually forms a part of the valve mechanism. Hence an extremely simple yet effective valve is formed. In the “at rest” state of the pump the tube 10 forms a seal over the ports 37 of the inlet valve 15 . This is shown in FIGS. 2 and 3.
[0053] [0053]FIG. 4, shows that when a negative pressure is applied to the chamber 11 a in housing 11 tube 10 is caused to expand and this expansion lifts the portion 10 a of tube 10 off the outer wall surface of the body 26 adjacent the end wall 27 thereby opening the port(s) 37 . This allows liquid from an input conduit (not shown) fixed to the inlet fitting 34 to flow into and fill the tube 10 . Outflow from the tube 10 is prevented due to the sealing effect of portion 10 b of the tube 10 over the outlet port(s) 37 of the valve body 26 of exhaust valve 16 .
[0054] When the air cylinder pressure increases by movement of the piston 20 toward the transfer passageway 18 , the tube 10 is forced to collapse inward (see FIG. 5) thereby increasing the pressure of liquid in the tube which forces the portion 10 b of tube 10 to move off the port(s) 37 of the body B of exhaust valve 16 . Fluid thus flows through the exhaust valve 16 and into an outlet conduit (not shown) attached to the outlet fitting 34 . This pressure increase in the chamber 11 a in housing 11 on the other hand causes the tube portion 10 a where it fits over body 26 of inlet valve 15 in the vicinity of port(s) 37 to maintain a good seal over the port(s) 37 of the inlet valve 15 .
[0055] [0055]FIG. 3 shows a chamber or clearance 38 formed in the wall of housing 11 by a counterboring within housing 11 adjacent inlet valve 15 . This provides a clearance for the tube 10 to be lifted by the negative pressure build up from the port end of the inlet valve body 26 such that liquid can flow through the ports 37 and into the main body of the tube 10 . Chamber 38 is shown occupied by the lifted wall portion 10 a of tube 10 in FIG. 4.
[0056] As the piston 20 retreats along cylinder 24 the tube 10 reverts to its non-deformed state thereby causing the area 10 a of tube 10 to once again seal over the port(s) 37 of outlet valve 16 .
[0057] With the pinch mechanism according to the present invention, no rigid pushers or rollers make contact with and pinch the tube. Therefore, significantly longer tube life is achieved.
[0058] Also efficient operation is achievable because the mechanism operates with very little friction, consequently motor power efficiency can be extremely high. Indeed, in applications where it may be desirable a battery power source could be used.
[0059] It is believed that the gradual build up of pressure acting on the tube 10 and the gradual development of the negative pressure in the chamber also results in less wear and tear on the tube 10 . Furthermore the gradual pressure changes (rather than a sudden change of the type typical with known mechanisms of this type) improves flow characteristics within the tube 10 can be achieved.
[0060] With known pumps of this type the means of driving the tube in the chamber can involve a compressed pressure source and a vacuum source. Consequently a complex arrangement of valves, control gear and compressors/vacuum pumps is required. Not only does this represent a capital cost in plant but also higher running costs. The present invention thus represents a radical departure by using the piston 20 in cylinder 19 with transfer port 25 to generate the required positive and negative pressures to operate the tube. The overall result is an effective and economic means of driving the pump with reduced maintenance and running costs.
[0061] Previous proposals to reduce the capital costs and running costs mentioned above with prior pumps of this type have included a piston in cylinder arrangement charged with a hydraulic fluid. However, such arrangements are prone to leakage thereby resulting in the need to routinely recharge the cylinder. Also leakage into the chamber is possible and if this leakage of hydraulic fluid takes place into the tube then a serious problem exists, especially if the pump is being used in a food or medical situation.
[0062] To overcome this latter problem it has been proposed to charge the cylinder with air or other gaseous medium. However, once again leakage can result in a drop off of performance and thus a need to routinely recharge the cylinder.
[0063] With the present invention there is no air consumption during operation. Any leakage which does occur (say due to a worn piston seal) is automatically replenished when the piston passes through the zero pressure point i.e. passes the transfer port 25 .
[0064] From a commercial point of view, the low number of parts making up the pump provides benefits not only at the initial costs but also ongoing costs. Because of the construction and its operation it is believed that maintenance costs can be kept low.
[0065] A further factor which contributes to the favourable maintenance characteristics of the pump is in the area of the seal(s) 22 on piston 20 . Because the pressure within cylinder 24 is essentially at atmospheric pressure when the seal(s) 22 pass over the ends of transfer port 25 there is little or no tendency for the seal(s) to be pushed into the port. Thus seal 22 is not subjected to damaging contact with the port 25 and hence a long seal life is achieved.
[0066] The pump exhibits good characteristics of dry and wet priming. With the second embodiment the effectiveness of the valves will ensure that no siphoning occurs.
[0067] With the present invention there is no requirement that tube 10 have rebound characteristics. Indeed tube 10 can be of thin wall construction (e.g. in the nature of a membrane) which exhibits no rebound characteristics. For the food and medical industries the thin wall tube can be made of a suitable grade polyurethane.
[0068] Because of its design the pinch mechanism when in a pump configuration develops good suction aided by the negative pressure on the inlet strike. The level of suction can be altered by design. Output pressure can be preset by adjustment to the air cylinder. The output pressure is also limited by the drive pressure ensuring the pump, and the equipment that may be attached, will not overload. A pressure relief switch is therefore not required. Furthermore without heat generation or abrasion dry running can occur without damage.
[0069] A problem which often arises with pumps of this type occurs at the inlet valve. The operation of the inlet valve generally relies on the negative pressure in the tube to lift valve element from the valve seat. This requires a pressure differential to occur at the valve and consequently a pressure drop will take place which can have an adverse impact on the flow into the tube.
[0070] With the present invention, however, the operation of the inlet valve is actively driven by the negative pressure build up in the chamber. Consequently there is no or little pressure differential across the inlet valve. This active control of the inlet valve also occurs at closure of the valve due to the build up of greater than atmospheric pressure in the chamber.
[0071] In the modified form of the invention the port 17 can be located immediately adjacent the inlet valve 15 . Consequently the pressure change in the chamber commences in the vicinity of the valve which results in even better active control of the lifting from or sealing on of the tube 10 with the port(s) 37 .
[0072] It is envisaged that a series of housings and tubes could be located adjacent one another and operated simultaneously from one source of positive pressure followed by the application from the same source or a separate source of a negative pressure. Therefore one driving arrangement could be used to operate a series of tubes 10 within housing II.
[0073] Other modifications, common uses and different arrangements will be apparent to those skilled in the art within the context of the present invention. | A pinch mechanism, which can be used as part of a pump, includes a deformable tube ( 10 ) enclosed within a body ( 11 ) which has a first chamber ( 11 a ). The deformable tube ( 10 ) defines a flow passage. A second chamber ( 19 ) is coupled via passage ( 17 ) to the first chamber ( 11 a ). A piston ( 20 ) is located within the second chamber ( 19 ) and movable between first and second positions. Upon moving to the first position a pressure increase occurs in the first chamber ( 11 a ). Upon moving to the second position a negative pressure is created in the first chamber ( 11 a ). A vent means ( 25 ) is located at a point during movement of the piston ( 20 ) between the first and second positions which enables pressure equalisation within the second chamber ( 19 ) to occur. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 12/652,412, filed on Jan. 5, 2010. U.S. patent application Ser. No. 12/652,412 is a continuation of U.S. patent application Ser. No. 12/033,446, filed on Feb. 19, 2008. U.S. patent application Ser. No. 12/033,446 is a continuation of U.S. Pat. No. 7,362,283, issued on Apr. 22, 2008. U.S. Pat. No. 7,362,283 is a continuation of PCT/EP01/10589, filed on Sep. 13, 2001. U.S. patent application Ser. No. 12/652,412, U.S. patent application Ser. No. 12/033,446, U.S. Pat. No. 7,362,283 and International Patent Application PCT/EP01/10589 are incorporated herein by reference.
OBJECT AND BACKGROUND OF THE INVENTION
[0002] 1. Technical Field of the Invention
[0003] The present invention relates generally to a new family of antenna ground-planes of reduced size and enhanced performance based on an innovative set of geometries. These new geometries are known as multilevel and space-filling structures, which had been previously used in the design of multiband and miniature antennas. A throughout description of such multilevel or space-filling structures can be found in “Multilevel Antennas” (Patent Publication No. WO01/22528) and “Space-Filling Miniature Antennas” (Patent Publication No. WO01/54225).
[0004] 2. Description of the Related Art
[0005] The current invention relates to the use of such geometries in the ground-plane of miniature and multiband antennas. In many applications, such as for instance mobile terminals and handheld devices, it is well known that the size of the device restricts the size of the antenna and its ground-plane, which has a major effect on the overall antenna performance. In general terms, the bandwidth and efficiency of the antenna are affected by the overall size, geometry, and dimensions of the antenna and the ground-plane. A report on the influence of the ground-plane size in the bandwidth of terminal antennas can be found in the publication “Investigation on Integrated Antennas for GSM Mobile Phones”, by D. Manteuffel, A. Bahr, I. Wolff, Millennium Conference on Antennas & Propagation, ESA, AP2000, Davos, Switzerland, April 2000. In the prior art, most of the effort in the design of antennas including ground-planes (for instance microstrip, planar inverted-F or monopole antennas) has been oriented to the design of the radiating element (that is, the microstrip patch, the PIFA element, or the monopole arm for the examples described above), yet providing a ground-plane with a size and geometry that were mainly dictated by the size or aesthetics criteria according to every particular application.
[0006] One of the key issues of the present invention is considering the ground-plane of an antenna as an integral part of the antenna that mainly contributes to its radiation and impedance performance (impedance level, resonant frequency, bandwidth). A new set of geometries are disclosed here, such a set allowing to adapt the geometry and size of the ground-plane to the ones required by any application (base station antennas, handheld terminals, cars, and other motor-vehicles and so on), yet improving the performance in terms of, for instance, bandwidth, Voltage Standing Wave Ratio (hereafter VSWR), or multiband behaviour.
[0007] The use of multilevel and space-filling structures to enhance the frequency range an antenna can work within was well described in patent publication numbers WO01/22528 and WO01/54225. Such an increased range is obtained either through an enhancement of the antenna bandwidth, with an increase in the number of frequency bands, or with a combination of both effects. In the present invention, said multilevel and space-filling structures are advantageously used in the ground-plane of the antenna obtaining this way either a better return loss or VSWR, a better bandwidth, a multiband behaviour, or a combination of all these effects. The technique can be seen as well as a means of reducing the size of the ground-plane and therefore the size of the overall antenna.
[0008] A first attempt to improve the bandwidth of microstrip antennas using the ground-plane was described by T. Chiou, K. Wong, “Designs of Compact Microstrip Antennas with a Slotted Ground Plane”. IEEE-APS Symposium, Boston, 8-12 July, 2001. The skilled in the art will notice that even though the authors claim the improved performance is obtained by means of some slots on the antenna ground-plane, those were unintentionally using a very simple case of multilevel structure to modify the resonating properties of said ground-plane. In particular, a set of two rectangles connected through three contact points and a set of four rectangles connected through five contact points were described there. Another example of an unintentional use of a multilevel ground structure in an antenna ground-plane is described in U.S. Pat. No. 5,703,600. There, a particular case of a ground-plane composed by three rectangles with a capacitive electromagnetic coupling between them was used. It should be stressed that neither in the paper by Chiou and Wong, nor in patent U.S. Pat. No. 5,703,600, the general configuration for space-filling or multilevel structures were disclosed or claimed, so the authors were not attempting to use the benefits of said multilevel or space-filling structures to improve the antenna behaviour.
[0009] Some of the geometries described in the present invention are inspired in the geometries already studied in the 19.sup.th century by several mathematicians such as Giusepe Peano and David Hilbert. In all said cases the curves were studied from the mathematical point of view but were never used for any practical engineering application. Such mathematical abstractions can be approached in a practical design by means of the general space-filling curves described in the present invention. Other geometries, such as the so called SZ, ZZ, HilbertZZ, Peanoinc, Peanodec or PeanoZZ curves described in patent publication WO01/54225 are included in the set of space-filling curves used in an innovative way in the present invention. It is interesting to notice that in some cases, such space-filling curves can be used to approach ideal fractal shapes as well.
[0010] The dimension (D) is often used to characterize highly complex geometrical curves and structures such as those described in the present invention. There exists many different mathematical definitions of dimension but in the present document the box-counting dimension (which is well-known to those skilled in mathematics theory) is used to characterize a family of designs. Again, the advantage of using such curves in the novel configuration disclosed in the present invention is mainly the overall antenna miniaturization together with and enhancement of its bandwidth, impedance, or multiband behaviour.
[0011] Although usually not as efficient as the general space-filling curves disclosed in the present invention, other well-known geometries such as meandering and zigzag curves can also be used in a novel configuration according to the spirit and scope of the present invention. Some descriptions of using zigzag or meandering curves in antennas can be found for instance in patent publication WO96/27219, but it should be noticed that in the prior-art such geometries were used mainly in the design of the radiating element rather than in the design of the ground-plane as it is the purpose and basis of several embodiments in the present invention.
[0012] It is known the European Patent EP-688.040 which discloses a bidirectional antenna including a substrate having a first and second surfaces. On a second surface are arranged respectively, a ground conductor formed by a single surface, a strip conductor and a patch conductor.
SUMMARY OF THE INVENTION
[0013] The key point of the present invention is shaping the ground-plane of an antenna in such a way that the combined effect of the ground-plane and the radiating element enhances the performance and characteristics of the whole antenna device, either in terms of bandwidth, VSWR, multiband behaviour, efficiency, size, or gain. Instead of using the conventional solid geometry for ground-planes as commonly described in the prior art, the invention disclosed here introduces a new set of geometries that forces the currents on the ground-plane to flow and radiate in a way that enhances the whole antenna behaviour.
[0014] The basis of the invention consists of breaking the solid surface of a conventional ground-plane into a number of conducting surfaces (at least two of them) said surfaces being electromagnetically coupled either by the capacitive effect between the edges of the several conducting surfaces, or by a direct contact provided by a conducting strip, or a combination of both effects.
[0015] The resulting geometry is no longer a solid, conventional ground-plane, but a ground-plane with a multilevel or space-filling geometry, at least in a portion of said ground-plane.
[0016] A Multilevel geometry for a ground-plane consists of a conducting structure including a set of polygons, all of said polygons featuring the same number of sides, wherein said polygons are electromagnetically coupled either by means of a capacitive coupling or ohmic contact, wherein the contact region between directly connected polygons is narrower than 50% of the perimeter of said polygons in at least 75% of said polygons defining said conducting ground-plane. In this definition of multilevel geometry, circles and ellipses are included as well, since they can be understood as polygons with infinite number of sides.
[0017] On the other hand, an Space-Filling Curve (hereafter SFC) is a curve that is large in terms of physical length but small in terms of the area in which the curve can be included. More precisely, the following definition is taken in this document for a space-filling curve: a curve composed by at least ten segments which are connected in such a way that each segment forms an angle with their neighbours, that is, no pair of adjacent segments define a larger straight segment, and wherein the curve can be optionally periodic along a fixed straight direction of space if, and only if, the period is defined by a non-periodic curve composed by at least ten connected segments and no pair of said adjacent and connected segments defines a straight longer segment. Also, whatever the design of such SFC is, it can never intersect with itself at any point except the initial and final point (that is, the whole curve can be arranged as a closed curve or loop, but none of the parts of the curve can become a closed loop). A space-filling curve can be fitted over a flat or curved surface, and due to the angles between segments, the physical length of the curve is always larger than that of any straight line that can be fitted in the same area (surface) as said space-filling curve. Additionally, to properly shape the ground-plane according to the present invention, the segments of the SFC curves included in said ground-plane must be shorter than a tenth of the free-space operating wavelength.
[0018] Depending on the shaping procedure and curve geometry, some infinite length SFC can be theoretically designed to feature a Haussdorf dimension larger than their topological-dimension. That is, in terms of the classical Euclidean geometry, it is usually understood that a curve is always a one-dimension object; however when the curve is highly convoluted and its physical length is very large, the curve tends to fill parts of the surface which supports it; in that case, the Haussdorf dimension can be computed over the curve (or at least an approximation of it by means of the box-counting algorithm) resulting in a number larger than unity. The curves described in FIG. 2 are some examples of such SFC; in particular, drawings 11 , 13 , 14 , and 18 show some examples of SFC curves that approach an ideal infinite curve featuring a dimension D=2. As known by those skilled in the art, the box-counting dimension can be computed as the slope of the straight portion of a log-log graph, wherein such a straight portion is substantially defined as a straight segment. For the particular case of the present invention, said straight segment will cover at least an octave of scales on the horizontal axis of the log-log graph.
[0019] Depending on the application, there are several ways for establishing the required multilevel and space-filling metallic pattern according to the present invention. Due to the special geometry of said multilevel and space-filling structures, the current distributes over the ground-plane in such a way that it enhances the antenna performance and features in terms of:
[0000] (a) Reduced size compared to antennas with a solid ground-plane.
(b) Enhanced bandwidth compared to antennas with a solid ground-plane.
(c) Multifrequency performance.
(d) Better VSWR feature at the operating band or bands.
(e) Better radiation efficiency.
(f) Enhanced gain.
[0020] It will be clear that any of the general and newly described ground-planes of the present invention can be advantageously used in any of the prior-art antenna configurations that require a ground-plane, for instance: antennas for handheld terminals (cellular or cordless telephones, PDAs, electronic pagers, electronic games, or remote controls), base station antennas (for instance for coverage in micro-cells or pico-cells for systems such as AMPS, GSM900, GSM1800, UMTS, PCS1900, DCS, DECT, WLAN, . . . ), car antennas, and so on. Such antennas can usually take the form of microstrip patch antennas, slot-antennas, Planar Inverted-F (PIFA) antennas, monopoles and so on, and in all those cases where the antenna requires a ground-plane, the present invention can be used in an advantageous way. Therefore, the invention is not limited to the aforementioned antennas. The antenna could be of any other type as long as a ground-plane is included.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] For a better understanding of the present invention, reference will now be made to the appended drawings in which:
[0022] FIG. 1 shows a comparison between two prior art ground-planes and a new multilevel ground-plane. Drawing 1 shows a conventional ground-plane formed by only one solid surface (rectangle, prior-art), whereas drawing 2 shows a particular case of ground-plane that has been broken in two surfaces 5 and 6 (rectangles) connected by a conducting strip 7 , according to the general techniques disclosed in the present invention. Drawing 3 shows a ground-plane where the two conducting surfaces 5 and 6 , separated by a gap 4 , are being connected through capacitive effect (prior-art).
[0023] FIG. 2 shows some examples of SFC curves. From an initial curve 8 , other curves 9 , 10 , and 11 are formed (called Hilbert curves). Likewise, other set of SFC curves can be formed, such as set 12 , 13 , and 14 (called SZ curves); set 15 and 16 (known as ZZ curves); set 17 , 18 , and 19 (called HilbertZZ curves); set 20 (Peanodec curve); and set 21 (based on the Giusepe Peano curve).
[0024] FIG. 3A shows a perspective view of a conventional (prior-art) Planar Inverted-F Antenna or PIFA ( 22 ) formed by a radiating antenna element 25 , a conventional solid surface ground-plane 26 , a feed point 24 coupled somewhere on the patch 25 depending upon the desired input impedance, and a short-circuit 23 coupling the patch element 25 to the ground-plane 26 . FIG. 3B shows a new configuration ( 27 ) for a PIFA antenna, formed by an antenna element 30 , a feed point 29 , a short-circuit 28 , and a particular example of a new ground-plane structure 31 formed by both multilevel and space-filling geometries.
[0025] FIG. 4A is a representational perspective view of the conventional configuration (prior-art) for a monopole 33 over a solid surface ground-plane 34 . FIG. 4B shows an improved monopole antenna configuration 35 where the ground-plane 37 is composed by multilevel and space-filling structures.
[0026] FIG. 5A shows a perspective view of a patch antenna system 38 (prior-art) formed by a rectangular radiating element patch 39 and a conventional ground-plane 40 . FIG. 5B shows an improved antenna patch system composed by a radiating element 42 and a multilevel and space-filling ground-plane 43 .
[0027] FIG. 6 shows several examples of different contour shapes for multilevel ground-planes, such as rectangular ( 44 , 45 , and 46 ) and circular ( 47 , 48 , and 49 ). In this case, circles and ellipses are taken as polygons with infinite number of sides.
[0028] FIG. 7 shows a series of same-width multilevel structures (in this case rectangles), where conducting surfaces are being connected by means of conducting strips (one or two) that are either aligned or not aligned along a straight axis.
[0029] FIG. 8 shows that not only same-width structures can be connected via conducting strips. More than one conducting strips can be used to interconnect rectangular polygons as in drawings 59 and 61 . Also it is disclosed some examples of how different width and length conducting strips among surfaces can be used within the spirit of the present invention.
[0030] FIG. 9 shows alternative schemes of multilevel ground-planes. The ones being showed in the FIGS. 68 to 76 ) are being formed from rectangular structures, but any other shape could have been used.
[0031] FIG. 10 shows examples ( 77 and 78 ) of two conducting surfaces ( 5 and 6 ) being connected by one ( 10 ) or two ( 9 and 10 ) SFC connecting strips.
[0032] FIG. 11 shows examples wherein at least a portion of the gap between at least two conducting surfaces is shaped as an SPC connecting strip.
[0033] FIG. 12 shows a series of ground-planes where at least one of the parts of said ground-planes is shaped as SFC. In particular, the gaps ( 84 , 85 ) between conducting surfaces are shaped in some cases as SFC.
[0034] FIG. 13 shows another set of examples where parts of the ground-planes such as the gaps between conducting surfaces are being shaped as SFC.
[0035] FIG. 14 shows more schemes of ground-planes ( 91 and 92 ) with different SFC width curves ( 93 and 94 ). Depending on the application, configuration 91 can be used to minimize the size of the antenna while configuration 92 is preferred for enhancing bandwidth in a reduced size antenna while reducing the backward radiation.
[0036] FIG. 15 shows a series of conducting surfaces with different widths being connected through SFC conducting strips either by direct contact ( 95 , 96 , 97 , 98 ) or by capacitive effect (central strip in 98 ).
[0037] FIG. 16 shows examples of multilevel ground-planes (in this case formed by rectangles).
[0038] FIG. 17 shows another set examples of multilevel ground-planes.
[0039] FIG. 18 shows examples of multilevel ground-planes where at least two conducting surfaces are being connected through meandering curves with different lengths or geometries. Some of said meandering lines can be replaced by SFC curves if a further size reduction or a different frequency behaviour is required.
[0040] FIG. 19 shows examples of antennas wherein the radiating element has substantially the same shape as the ground-plane, thereby obtaining a symmetrical or quasymmetrical configuration, and where said radiating element is placed parallel (drawing 127 ) or orthogonal (drawing 128 ) to said ground-plane.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] In order to construct an antenna assembly according to embodiments of our invention, a suitable antenna design is required. Any number of possible configurations exists, and the actual choice of antenna is dependent, for instance, on the operating frequency and bandwidth, among other antenna parameters. Several possible examples of embodiments are listed hereinafter. However, in view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention. In particular, different materials and fabrication processes for producing the antenna system may be selected, which still achieve the desired effects. Also, it would be clear that other multilevel and space-filling geometries could be used within the spirit of the present invention.
[0042] FIG. 3A shows in a manner already known in prior art a Planar Inverted-F ( 22 ) Antenna (hereinafter PIFA Antenna) being composed by a radiating antenna element 25 , a conventional solid surface ground-plane 26 , a feed point 24 coupled somewhere on the patch 25 depending upon the desired input impedance, and a short-circuit 23 coupling the patch element 25 to the ground-plane 26 . The feed point 24 can be implemented in several ways, such a coaxial cable, the sheath of which is coupled to the ground-plane and the inner conductor 24 of which is coupled to the radiating conductive element 25 . The radiating conductive element 25 is usually shaped like a quadrangle, but several other shapes can be found in other patents or scientific articles. Shape and dimensions of radiating element 25 will contribute in determining operating frequency of the overall antenna system. Although usually not considered as a part of the design, the ground-plane size and geometry also has an effect in determining the operating frequency and bandwidth for said PIFA. PIFA antennas have become a hot topic lately due to having a form that can be integrated into the per se known type of handset cabinets.
[0043] Unlike the prior art PIFA ground-planes illustrated in FIG. 3A , the newly disclosed ground-plane 31 according to FIG. 3B is composed by multilevel and space-filling structures obtaining this way a better return loss or VSWR, a better bandwidth, and multiband behaviour, along with a compressed antenna size (including ground-plane). The particular embodiment of PIFA 27 is composed by a radiating antenna element 30 , a multilevel and space-filling ground-plane 31 , a feed point 29 coupled somewhere on the patch 30 , and a short-circuit 28 coupling the patch element 30 to the ground-plane 31 . For the sake of clarity but without loss of generality, a particular case of multilevel ground-plane 31 is showed, where several quadrangular surfaces are being electromagnetically coupled by means of direct contact through conducting strips and said polygons, together with an SFC and a meandering line. More precisely, the multilevel structure is formed with 5 rectangles, said multilevel structure being connected to a rectangular surface by means of SFC ( 8 ) and a meandering line with two periods. It is clear to those skilled in the art that those surfaces could have been any other type of polygons with any size, and being connected in any other manner such as any other SFC curve or even by capacitive effect. For the sake of clarity, the resulting surfaces defining said ground-plane are lying on a common flat surface, but other conformal configurations upon curved or bent surfaces could have been used as well.
[0044] For this preferred embodiment, the edges between coupled rectangles are either parallel or orthogonal, but they do not need to be so. Also, to provide the ohmic contact between polygons several conducting strips can be used according to the present invention. The position of said strips connecting the several polygons can be placed at the center of the gaps as in FIG. 6 and drawings 2 , 50 , 51 , 56 , 57 , 62 , 65 , or distributed along several positions as shown in other cases such as for instance drawings 52 or 58 .
[0045] In some preferred embodiments, larger rectangles have the same width (for instance FIG. 1 and FIG. 7 ) but in other preferred embodiments they do not (see for instance drawings 64 through 67 in FIG. 8 ). Polygons and/or strips are linearly arranged with respect an straight axis (see for instance 56 and 57 ) in some embodiments while in others embodiments they are not centered with respect to said axis. Said strips can also be placed at the edges of the overall ground-plane as in, for instance, drawing 55 , and they can even become arranged in a zigzag or meandering pattern as in drawing 58 where the strips are alternatively and sequentially placed at the two longer edges of the overall ground-plane.
[0046] Some embodiments like 59 and 61 , where several conducting surfaces are coupled by means of more than one strip or conducting polygon, are preferred when a multiband or broadband behaviour is to be enhanced. Said multiple strip arrangement allows multiple resonant frequencies which can be used as separate bands or as a broad-band if they are properly coupled together. Also, said multiband or broad-band behaviour can be obtained by shaping said strips with different lengths within the same gap.
[0047] In other preferred embodiments, conducting surfaces are connected by means of strips with SFC shapes, as in the examples shown in FIG. 3 , 4 , 5 , 10 , 11 , 14 , or 15 . In said configurations, SFC curves can cover even more than the 50% of the area covered by said ground-plane as it happens in the cases of FIG. 14 . In other cases, the gap between conducting surfaces themselves is shaped as an SFC curve as shown in FIG. 12 or 13 . In some embodiments, SFC curves feature a box-counting dimension larger than one (at least for an octave in the abscissa of the log-log graph used in the box-counting algorithm) and can approach the so called Hilbert or Peano curves or even some ideally infinite curves known as fractal curves.
[0048] Another preferred embodiment of multilevel and space-filling ground-plane is the monopole configuration as shown in FIG. 4 . FIG. 4A shows a prior art antenna system 32 composed by a monopole radiating element 33 over a common and conventional solid surface ground-plane 34 . Prior art patents and scientific publications have dealt with several one-piece solid surfaces, being the most common ones circular and rectangular. However, in the new ground-plane configuration of our invention, multilevel and space-filling structures can be used to enhance either the return loss, or radiation efficiency, or gain, or bandwidth, or a combination of all the above, while reducing the size compared to antennas with a solid ground-plane. FIG. 4B shows a monopole antenna system 35 composed by a radiating element 36 and a multilevel and space-filling ground-plane 37 . Here, the arm of the monopole 33 is presented as a cylinder, but any other structure can be obviously taken instead (even helical, zigzag, meandering, fractal, or SFC configurations, to name a few).
[0049] To illustrate that several modifications of the antenna can be done based on the same principle and spirit of the present invention, another preferred embodiment example is shown in FIG. 5 , based on the patch configuration. FIG. 5A shows an antenna system 38 that consist of a conventional patch antenna with a polygonal patch 39 (squared, triangular, pentagonal, hexagonal, rectangular, or even circular, multilevel, or fractal, to name just a few examples) and a common and conventional one-piece solid ground-plane 40 . FIG. 5B shows a patch antenna system 41 that consists of a radiating element 42 (that can have any shape or size) and a multilevel and space-filling ground-plane 43 . The ground-plane 43 being showed in the drawing is just an example of how multilevel and space-filling structures can be implemented on a ground-plane.
[0050] Preferably, the antenna, the ground-plane or both are disposed on a dielectric substrate. This may be achieved, for instance, by etching techniques as used to produce PCBs, or by printing the antenna and the ground-plane onto the substrate using a conductive ink. A low-loss dielectric substrate (such as glass-fibre, a teflon substrate such as Cuclad® or other commercial materials such as Rogers® 4003 well-known in the art) can be placed between said patch and ground-plane. Other dielectric materials with similar properties may be substituted above without departing from the intent of the present invention. As an alternative way to etching the antenna and the ground-plane out of copper or any other metal, it is also possible to manufacture the antenna system by printing it using conductive ink. The antenna feeding scheme can be taken to be any of the well-known schemes used in prior art patch antennas as well, for instance: a coaxial cable with the outer conductor connected to the ground-plane and the inner conductor connected to the patch at the desired input resistance point; a microstrip transmission line sharing the same ground-plane as the antenna with the strip capacitively coupled to the patch and located at a distance below the patch, or in another embodiment with the strip placed below the ground-plane and coupled to the patch through an slot, and even a microstrip transmission line with the trip co-planar to the patch. All these mechanisms are well known from prior art and do not constitute an essential part of the present invention. The essential part of the present invention is the shape of the ground-plane (multilevel and/or space-filling), which contributes to reducing the size with respect to prior art configurations, as well as enhancing antenna bandwidth, VSWR, and radiation efficiency.
[0051] It is interesting to notice that the advantage of the ground-plane geometry can be used in shaping the radiating element in a substantially similar way. This way, a symmetrical or quasi-symmetrical configuration is obtained where the combined effect of the resonances of the ground-plane and radiating element is used to enhance the antenna behavior. A particular example of a microstrip ( 127 ) and monopole ( 128 ) antennas using said configuration and design in drawing 61 is shown in FIG. 19 , but it appears clear to any skilled in the art that many other geometries (other than 61 ) could be used instead within the same spirit of the invention. Drawing 127 shows a particular configuration with a short-circuited patch ( 129 ) with shorting post, feeding point 132 and said ground-plane 61 , but other configurations with no shorting post, pin, or strip are included in the same family of designs. In the particular design of the monopole ( 128 ), the feeding post is 133 .
[0052] Although various embodiments of the method and apparatus of the present invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications, and substitutions without departing from the spirit and scope of the invention as set forth in the foregoing specification and following claims. | An antenna system includes one or more conductive elements acting as radiating elements, and a multilevel or space-filling ground-plane, wherein said ground-plane has a particular geometry which affects the operating characteristics of the antenna. The return loss, bandwidth, gain, radiation efficiency, and frequency performance can be controlled through multilevel and space-filling ground-plane design. Also, said ground-plane can be reduced compared to those of antennas with solid ground-planes. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a control for a vehicular powertrain comprising a fuel-controlled engine and a multiple-ratio drivetrain, including a multiple-speed transmission and a single- or mulitple-speed drive axle assembly. In particular, the present invention relates to a powertrain control wherein the maximum output torque of the engine is limited as a function of engaged drivetrain ratio.
2. Description of the Prior Art
Vehicular drivetrains including multiple-speed transmissions, usually compound transmissions, or simple transmissions coupled with multiple-speed axles, having 7, 9, 10, 13, 16, 18 or more forward speed ratios, are well known in the prior art, especially for heavy-duty vehicles, as may be seen by reference to U.S. Pat. Nos. 5,370,013; 5,527,237 and 4,754,665, the disclosures of which are incorporated herein by reference.
Control systems and methods for calculating engine output torque (also called “flywheel torque”) are known in the prior art, as may be seen by reference to U.S. Pat. No. 5,509,867, the disclosure of which is incorporated herein by reference.
Automated and manual transmission systems wherein engine output torque is controlled and/or limited as a function of engaged gear ratio and/or vehicle speed are known in the prior art, as may be seen by reference to U.S. Pat. Nos. 5,477,827; 5,797,110; 5,457,633; 4,889,014; 5,738,606; 5,679,096 and 5,876,302, the disclosures of which are incorporated herein by reference. As is known, modern vehicular powertrains usually include electronically controlled engines, which may be controlled as to engine speed and/or engine torque. By way of example, according to the SAE J-1939 data link protocol, commands may be issued to the engine for fueling of the engine in accordance with (a) driver's fuel demand, (b) a requested engine speed, (c) a requested engine torque and/or (d) a requested maximum engine torque and/or engine speed.
SUMMARY OF THE INVENTION
In accordance with the present invention, an improved control system/method for a vehicular powertrain is provided, which will tend to maximize vehicle performance while protecting the drivetrain from possible damage and/or undue wear caused by allowing excessive torque to be applied thereto under certain vehicle operating conditions. The foregoing is accomplished by limiting engine output torque to a first maximum value when the drivetrain is in a start ratio condition, by limiting engine output torque to a second maximum value when the drivetrain is in an intermediate ratio (the second maximum value being greater than the first maximum value), allowing engine torque to equal a third maximum value greater than the second maximum value when the transmission is in a direct drive or 1:1 ratio, and allowing engine torque to equal a fourth maximum value when the transmission is in an overdrive ratio condition (the fourth maximum value being less than the third maximum value but greater than the second maximum value).
Accordingly, it is an object of the present invention to provide a new and improved engine output torque control for a vehicular drivetrain system, preferably a vehicular powertrain system including a transmission having a direct drive ratio.
This and other objects and advantages of the present invention will become apparent from a reading of the description of the preferred embodiment taken in connection with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a vehicular powertrain system including an automated mechanical transmission system.
FIGS. 2A and 2B are charts illustrating the drive ratios and allowable drivetrain input torques for a typical heavy-duty vehicle powertrain system including a drivetrain having, respectively, a 7-speed and an 18-speed overdrive transmission.
FIG. 3 is a flow chart representation of the control of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A vehicular powertrain system 10 of the type advantageously utilizing the control of the present invention may be seen by reference to FIG. 1 . For purposes of illustration, system 10 is an automated mechanical transmission system including a fuel-controlled internal combustion engine 12 (such as a well-known diesel engine or the like), a multiple-speed mechanical transmission 14 , and a non-positive coupling 16 for drivingly coupling the engine 12 to the transmission 14 . Typically, non-positive coupling 16 will be a torque converter or a friction master clutch. The transmission 14 further includes an output shaft 20 for driving the vehicle drive axles 22 . The drive axles may be of the single-speed or mulitple-speed type.
Transmission 14 may be of the known mechanical type utilizing positive jaw clutches to engage and disengage selected gears to shafts for changing the ratio of input shaft rotational speed (IS) to output shaft rotational speed (OS). Transmissions of this type may be seen by reference to U.S. Pat. Nos. 4,764,665; 5,385,056; 5,390,561 and 5,416,698.
System 10 may include a plurality of sensors for providing input signals 24 to a microprocessor-based control unit 26 , which will process the input signals according to logic rules to generate command output signals 28 to various system actuators.
Speed sensors 30 , 32 and 34 may be provided to provide input signals to the controller indicative of engine speed (ES), transmission input shaft speed (IS), and transmission output shaft speed (OS), respectively. A sensor 36 may be provided to provide an input signal indicative of the operator setting of the throttle pedal. A driver control console 38 is provided to allow the operator to select a transmission mode and to provide an input signal, GR, indicative thereof to the controller 26 .
An engine controller 40 , preferably microprocessor-based, may be provided for controlling fueling of the engine and for providing information to a data link, DL, indicative of the operating parameters of the engine. Preferably, the data link will comply with a known protocol, such as SAE J-1939 or the like. An actuator 42 may be provided for operating the non-positive coupling 16 . A transmission actuator 44 may be provided for operating the transmission 14 and for providing signals indicative of the engaged gear ratio and/or other transmission operating parameters. Engaged ratio also may be calculated by comparing the rotational speeds of the input and output shafts.
As used in this application, and as commonly used in the vehicular industry, the term “powertrain” will refer to the engine 12 , coupling 16 , transmission 14 and drive axles 12 , while the term “drivetrain” will refer to the coupling 16 , the transmission 14 and the axles 22 .
Transmission 14 is illustrated as an 18 -forward-speed transmission having a direct drive (1:1.00) ratio and two overdrive ratios (see FIG. 2 B). As is well known, in the direct drive ratio, the shafts are directly coupled and torque is not applied to the gears; accordingly, a much higher torque may be applied to the transmission in direct drive without damaging or causing excessive wear to the gears. It also is known that the higher rotational speeds associated with overdrive (i.e., ratios wherein output shaft rotational speed exceeds input shaft rotational speed) allows a higher input torque to be applied to the transmission than in greater than 1:1.00 reduction ratios without risking damage and/or undue wear.
According to the present invention, engine torque is limited to one of four maximum values according to the sensed or expected engaged ratio. FIG. 2A illustrates the application of the present invention to a 7-speed overdrive transmission.
In the start ratios, usually 1st through 6th in an 18-speed transmission, engine output torque is limited to a first maximum value (A). In the intermediate ratios, usually 7th through 15th in an 18-speed transmission, engine output torque is limited to a second maximum value (B). In direct, engine output torque is limited to a third maximum value (C). Value C may equal the maximum output of the engine. In overdrive ratios, 17th and 18th in the illustrated transmission, engine torque is limited to a fourth maximum value (D).
The maximum torque values are related as follows:
A<B<C>D and
B<D
Typical values of the maximum torque references are seen in FIGS. 2A and 2B, which are provided by way of example. In FIG. 2B, values for an RTLO 18918B transmission (available from Eaton Corporation, assignee of this application) and a typical heavy-duty vehicle diesel engine are provided.
FIG. 3 is a flow chart representation of the control of the present invention.
Torque values A, B, C and/or D may be ranges of values and/or may be subdivided.
Although the present invention has been described with a certain degree of particularity, it is understood that various modifications are possible without departing from the spirit and scope of the invention as hereinafter claimed. | A powertrain system ( 10 ) control for controlling engine ( 12 ) output torque as a function of engaged ratio of a transmission ( 14 ). Separate torque limits, A, B, C, D, respectively, are set for start ratios, intermediate ratios, direct ratio and overdrive ratios. The torque limits are set such that A<B<C>D and B<D. | 8 |
BACKGROUND OF THE INVENTION
The invention is related to a fuel injection pump as described by the preamble to the main claim. In a known fuel injection of this type, the pressure variation which is characteristic for the onset of injection is effected by means of engine characteristics, which has particular advantages in the case of starting an internal combustion engine when it is cold. A variation of the external air pressure is well-known to involve substantial difficulties in meeting the increasingly stringent requirements for substantially nontoxic exhaust gas, and these difficulties cannot be solved with the known means of pump control.
OBJECT AND SUMMARY OF THE INVENTION
The fuel injection, according to the invention, having the characteristics of the main claim, has the advantage of the prior art that an exhaust gas quality, once established, can continue to be maintained in a simple manner and, in particular, in a modular system (that is, one which can be subsequently installed), by means of an adjustment of the instant of the injection when there is a variation in pressure as a result of altitude. By means of varying the valve spring initial tension, the system functions as a closed-loop control system with respect to the quality of combustion.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of a preferred embodiment taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing of the injection pump having closed-loop control of the onset of injection;
FIG. 2 is a functional diagram;
FIG. 3 is a cross-sectional view of a barometric valve of the type used in this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the drawing an adjusting system 3 is adapted to engage the cam drive of a fuel injection pump 1 via a pin 2 for the adjustment of the instant of the onset of the injections. The adjusting system 3 is displaceable counter to a restoring spring 5 by means of a pressure fluid located in a work chamber 4; the further the piston is displaced toward the spring, the more the instant of injection is displaced toward "early" with respect to top dead center of the engine system. A supply pump 6 aspirates fuel from a fuel container 7 and delivers it into a suction chamber 8 of the injection pump 1, from which (not shown in further detail) the actual fuel injection pump is supplied with fuel and which communicates with the work chamber 4 via a bore 9 in the injecting system 3. The supply pressure of the supply pump 6 and thus the pressure in the suction chamber 8 is controlled in accordance with rpm via a pressure control valve 11, the pressure increasing proportionally with increasing rpm. This rpm-dependent pressure thus also prevails in the work chamber 4, so that with increasing rpm and thus increasing pressure the injection adjusting piston 3 is displaced toward "early".
In FIG. 2, a diagram is given in which the stroke s (ordinate) of the adjustment piston is plotted over the rpm n (abscissa). The line representing the injection adjustment for which the stroke and thus the early adjustment increases linearly with the rpm is designated by I. A line extending parallel thereto is designated II, and the course of the injection onset represented thereby would be necessary if the engine were driven at an altitude of 2,200 meters. The necessary adjustment of injection onset would necessitate a change of three angular degrees in the direction of "early".
In accordance with the invention, this is obtained by influencing the pressure in the suction chamber 8 and thus in the work chamber 4 via a pressure maintenance valve 12, which is controllable via a barometric box 13. The pressure control valve 11 has a piston 14, with which the spill port 15 is controllable and which is displaceable counter to a control spring 16 by means of the supplying fuel of the supply pump 6. The control system 14 has a throttle bore 17, by means of which the chambers on the two end faces are connected. The spring chamber 18 which encloses the control spring 16 has a discharge channel 19, in which the pressure maintenance valve 12 is disposed. The pressure maintenance valve 12, in turn, has a movable valve member 20, which is engaged by a valve spring 21. On the side remote from the valve member 20 the valve spring 21 is supported by the barometric box 13 which here comprises two diaphram boxes by means of which the initial tension of the valve spring 21 can be varied.
The functioning of this arrangement is such that at a pressure of approximately sea level the valve spring 21 is substantially relaxed and as a result the movable valve member 20 provides virtually no resistance to the flow of the fuel in the output channel 19. The pressure control valve 11 accordingly functions virtually unaffected by any factors, with a constant fuel quantity flowing out via the throttle 17. Now, as soon as the engine, installed for instance in a motor vehicle, reaches a different altitude, that is, as soon as the external pressure decreases, the valve spring 21 undergoes an increase of initial tension as a result of the relaxing function of the barometric box and the valve spring 21 exerts resistance against the outflow of the outflow channel 19. This resistance effects an increase of the pressure in the spring chamber 18 and thus reduces the spill cross section 15 of the pressure control valve 11. This, in turn, effects an increase of the pressure in the suction chamber 8 of the injection pump or the work chamber 4 of the pressure control valve 11, as a result of which a variation of the injection onset occurs toward "early".
In FIG. 3, a barometric valve 12 in accordance with the invention is shown in a structural embodiment. In the housing 23, a valve seat 24 is provided with which the movable valve member 20 cooperates, which in turn is under the force of the valve spring 21. The valve spring 21 is supported at the rear on the end wall of a blind bore 25 of a slide 26. The slide 26 is axially guided, sealing in a radial manner, in a housing 23 via a seal 27 and is displaceable by means of the barometric box 13. The opening pressure of the pressure maintenance valve 12 thus depends on the position of the slide 26, which is determined by the barometric box 13. The barometric box 13 functions counter to a support spring 28, which is supported on the one end on the housing 23 and on the other end on a spring plate 29, which engages the slide 26 via a securing ring 30. The spring force of the support spring 28 is approximately ten times as great as that of the valve spring 21. As a result, it is attained, on the one hand, that the adjustment unit comprising barometric box 13, piston 26 and spring 28 functions substantially independently of the work pressures of the pressure maintenance valve 12 and, on the other hand, it is by this means attainable that the valve spring 21 can be relieved to such an extent that the pressure maintenance valve 12 is virtually relieved of pressure; in other words, the fuel can flow virtually unthrottled through the outflow channel 19.
In accordance with the invention, it is also possible to switch the pressure maintenance valve 12 parallel to the pressure control valve 11.
The foregoing relates to a preferred exemplary embodiment of the invention, it being understood that other embodiments and variants thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | A fuel injection pump having a hydraulic adjuster for the instant of injection is proposed, in which in addition to the rpm-proportional adjustment of the onset of injection, a supplementary variation of the onset of injection occurs in accordance with pressure related to altitude. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application No. 61/928,921, filed Jan. 17, 2014, reference of which is hereby incorporated in its entirety.
BACKGROUND OF THE INVENTION
[0002] String vibration pickup (SVP) system pertains to technology and designs for stringed instruments such as guitars that allows pitch detection—conversion of string's musical note information from transduced acoustic. Common approaches to solving the problem of automatic pitch detection from guitars, especially electric guitars, is to take the summed audio signal from all of the strings (6 for guitar, for example) and implement signal processing and/or machine learning algorithms to do pitch detection. In such environments—summed complex signals with as many pitches as strings—can be problematic as isolating and following individual pitch from a summed signal is nontrivial. However, if a string's vibration information is isolated, pitch detection becomes simpler. One of the most popular ways to isolate individual string pickup is through pickups placed on the bridge of a guitar (which is more difficult to install) or using hexaphonic magnetic pickups—pickups placed underneath the string, ideally picking up each string individually—that have one magnet per string. The hexaphonic magnetic approach has been widely used by pickup designers and guitar manufacturers. However, due to the proximity of the strings, a certain amount of crosstalk and bleeding occurs.
SUMMARY OF THE INVENTION
[0003] One implementation relates to a string vibration pickup device. The device includes a sensor configured to engage a string to detect vibrations and a pickup base having a pickup in communication with the sensor to receive electrical signals indicative of sensed vibrations for the string.
[0004] Another implementation relates to a string vibration pickup device comprising a sensor configured to engage a string to detect vibrations. The device further includes a pickup base having a pickup in communication with the sensor to receive electrical signals indicative of sensed vibrations for the string. A processor is configured to determine pitch from the electronic signals.
[0005] Another implementation relates to a method of detecting pitch of a device. A sensor is placed in contact with a string of the device. Vibrations of the string are detected with the sensor. The detected vibrations are converted into an electrical signal. The electrical signal is transmitted to a processor, which processes the electrical signal to determine the pitch of the string.
[0006] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the following drawings and the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings.
[0008] FIG. 1 is a side-view of a direct string vibration pickup layout.
[0009] FIGS. 2A-E show a top down view of a number of different configuration and sensor placement.
[0010] FIG. 3 illustrates the place of sensors in relation to bridge in one embodiment.
[0011] FIGS. 4A and 4B illustrate a magnetic clamping system alone above and with sensors.
[0012] FIG. 5 illustrates subtle adjustments of sensors with respect to strings.
[0013] FIG. 6 illustrates a sensor at rest and securely fastened.
[0014] FIG. 7 illustrates Sensor pulled up, slid, and released in small, discrete sliding increments
[0015] FIG. 8 illustrates Example of 6 string guitar outputting 6 channels of audio for each string.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and made part of this disclosure.
[0017] Described herein are systems and methods for direct string vibration pickup (DSVP) system 101 follows an approach that is contrary to standard practice of leaving the string untouched. One implementation utilizes a concept of physically contacting the string to convert the mechanical energy into electrical energy. The electrical energy is collected with minimal cross-talk or bleed associated with indirect string vibration pickup. Pitch detection algorithms can then be applied to each string individually to determine pitch. This design allows for individual string vibration measurement with minimal crosstalk.
[0018] One such implementation is show in FIG. 1 . In a typical stringed instrument, a string 110 , which may be one of many, spans at least a distance between a first bridge 121 and a second bridge 122 or a head (not shown). A sensor 130 is positioned in contact with the string 110 . The sensor 130 is in electrical communication, such as via cable 131 , with the pickup base 140 . In one implementation, the sensor 130 is in communication with the pickup base 140 via a wireless connection such as WiFi or Bluetooth®. [ 0019 ] The sensor 130 comprises, in one implementation, a piezo film. In another implementation, the sensor 130 comprises a graphene film.
[0019] FIGS. 2A-E . below shows examples of different configurations for sensor 130 placement, though the invention is not limited to such configurations. FIG. 2A shows the sensor 130 that touches a string 110 from the side in perpendicular fashion. FIG. 2B shows the same configuration but from a different perspective—the string 110 going into the page. FIG. 2C shows a second configuration with the sensor 130 attached sideways and roughly centered on or below the string 110 . FIG. 2D shows the same configuration of FIG. 2B , but again with the view of the string 110 going into the page. FIG. 2E shows the sensor 130 attached along the string 110 . FIG. 2F shows the same configuration of FIG. 2E , but again with the view of the string 110 going into the page. FIG. 2G shows the sensor 130 leaning against the string 110 from the side. FIG. 2H shows the sensor 130 leaning against the string 110 from the top.
[0020] The configurations as shown in FIG. 2A-H allows individual sensors 130 to be attached to individual strings 110 , thereby allowing minimal to no crosstalk during the transduction process. In one implementation, the sensor 130 is placed near the bridge 121 of a guitar as shown in FIG. 3 . FIG. 3 illustrates implementation on a six-string guitar with each string 110 having an associated sensor 130 leaning against it side, similar to the configuration of FIG. 2G . This setup helps in minimizing loss of mechanical energy due to friction between the sensor and string providing close to natural string vibration. The configuration can be changed to fit other stringed instruments, including but limited to 4-string bass guitars.
[0021] The tilted/leaning configuration of sensors 130 in FIG. 3 have an important role as it allows the piezo film of the sensor 130 to make contact with the string 110 at all times due to the counteracting natural force of the film wanting to come to rest in its unbent, natural shape. To further help with robust contact and eliminate buzzing between the string 110 and sensor 130 , the sensor 130 may be magnetized. For example, the sensors 130 can be covered with a thin magnetic paste or the sensor 130 may be doped with a magnetic material. Various mechanisms may be utilized to attached the sensor 130 to the string 110 , including but not limited to removable mechanical attachment and adhesive (permanent and semi-permanent). In another implementation, the sensor 130 includes a clamp or two ridged placeholders to secure the sensor 130 to the string 110 . In this implementation, the string 110 fits between the two ridges or is held by a clamp.
[0022] An implementation of an enclosure 142 and pickup base 140 of the DSVP system is shown in FIGS. 4A-4B . The pickup base 140 serves to receive the signal from the sensor 130 . A single pickup base 140 may be associated with a single sensor 130 . In an alternative implementation, a single pickup base 140 is associated with a plurality of sensors 130 , as shown, for example, in FIG. 4B . In one implementation, the pickup base 140 is attachable, preferably removably attachable, to the instrument. For example, the base may be magnetic, such as comprising magnets in the pickup base 140 , which allow the DSVP system to be easily affixed onto standard electric guitar bridges.
[0023] The pickup base 140 may include an enclosure 142 to cover the internal components of the system 101 . In one implementation of the enclosure 142 , shown in FIG. 4A , the enclosure 142 includes a first arm 143 and a second arm 144 . Each arm 143 , 144 is L-Shaped and includes an adjustable connection mechanism to connect the first arm 143 and the second arm 144 such as by a securing screw 145 . The enclosure is affixed to the remainder of the pickup base 140 to help secure and position the pickup base 140 . In one implementation, the pickup base 140 stays secured on the bridge 121 of the guitar through magnetic force and the width can be adjusted to fit most guitars as the pickup base 140 is adjustable. The pickup base 140 can be further secured by using a securing screw that does not affect nor alter the guitar in any way. Note that the pickup base 140 , in one implementation, sits “on top” of the bridge and can, therefore, be shifted vertically. For implementations with instruments have a different configuration, the system 110 may also be attached below the strings 110 and in front of the bridge 121 .
[0024] In one implementation, best shown in FIG. 5 , the pickup base comprises an adjustable width. In the implementation of FIG. 5 , the pickup base 140 includes an adjustment of the total width and adjustment of the position of the pickup 138 . The pickup base 140 comprises a large base 148 that allows for an adjustment of rough width. For example, as shown in FIG. 5 , a first portion 148 a is nestable within a second portion 148 b of the large base 148 to allow for adjustment of the width of the large base 148 by an amount Z. In one implementation, the large base 148 is adjustable along with the enclosure 144 . For example, as slidable large base 148 has a width that changes as the enclosure 144 is adjusted. This effectively allows the pickup base 140 to be sized for placement on various instruments, such as to accommodate instruments with a wide range of string spacing and number of strings.
[0025] In addition, the pickup 138 is mounted on a small base 145 that is adjustable relative to the large base 148 . The small base 145 may be mounted in a slidable manner, such as on a track 146 . The small base 145 is adjustable by an amount Y, allowing for fine adjustment to the position of individual string positions on an instrument. Each small base 145 may be adjusted its own amount as indicated by Y and X in FIG. 5 . As also shown in FIG. 5 , the pickup base may comprise a large base 148 and multiple small bases 145 each having a pickup 138 associated with a sensor 130 (not shown in FIG. 5 ). To more finely position the sensors 130 with respect to the string 110 , adjustable screws 146 are provided in one implementation. A fastener 146 may be biased by a spring and secure the small base 145 to the large base 148 to allow for adjustment in two degrees. The fastener 146 may be a pin, bolt, screw, or the like. The pin 146 will secure the small base 145 against sliding and also provide some adjustment perpendicular to the plane along with the small base 145 slides. Further, as shown in FIG. 6 , a ridge 150 and groove structure 149 on the small base 145 and large base 148 may help to secure the small base 145 with respect to the large base 148 . The groove structure 149 may be created by spaces between a series of raised portions 151 .
[0026] In one implementation, the small base 145 is adjustable with respect to the large base 148 . For example, as shown in FIG. 7 , the large base 148 may have a slot (not shown) through which the fastener 146 may pass to secure the small base 145 . To reposition the small base 145 , the fastener 146 is removed, the small base 145 lifted from the large base 148 , slide or moved sideways then repositioned on the large base 148 . In one implementation such as shown in FIG. 7 having the ridge 150 and groove 149 structure for securing the large base 148 and small base 145 , the fastener 146 may be loosened but not removed to allow the small base 145 to be sufficiently moved off of the large base such that the ridge 150 and groove 149 are no longer engaged, allowing the small base 145 to slide. In addition, certain embodiments may not use a fastener 146 but may include a snap-fit or friction fit between the small base 145 and the large base 148 . The materials used for the pickup bases 140 will include acoustic absorption materials to further minimize cross-talk between individual sensors 130 . That is, the small bases ( 145 ), large bases ( 148 ), and fastener 146 may include materials to reduce vibration and bleed.
[0027] The overall system is shown in FIG. 8 , which consists of the pickup system 101 a single cable 109 from the pickup system 101 to an amplifier or audio interface [Not Shown]. In another implementation, the pickup system 101 may have an onboard signal processing unit and data is sent wirelessly via through standard wireless transmission technologies such as Bluetooth or WiFi.
[0028] The foregoing description of illustrative embodiments has been presented for purposes of illustration and of description. It is not intended to be exhaustive or limiting with respect to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosed embodiments. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents. | A string vibration pickup device and methods for using same. The device includes a sensor configured to engage a string to detect vibrations. A pickup base having a pickup in communication with the sensor receives electrical signals indicative of sensed vibrations for the string. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention related to a closed circuit rebreather wherein the carbon dioxide (CO 2 ) scrubbing material is imbedded within a body worn vest in order to minimize the profile of the rebreather as well as to use the natural breathing rhythm of the user to assist in the function of the rebreather.
2. Background of the Prior Art
Rebreathers are used in a wide variety of applications including military settings, especially underwater teams that desire to remain stealth and not have air bubbles surface as would be the case if using open circuit breathing apparatus. Other applications include mine rescue or other industries where poisonous gas may be present or oxygen absent, manned space vehicles and space suits where a person is effectively in a vacuum, hospital anesthesia breathing systems that supply appropriately proportioned gas mixtures to a patient without letting the gas escape to be breathed by hospital personnel, submarines, and oxygen hyperbaric chambers, among other applications.
The rebreather works by recirculating exhaled air from the user's breath based on the fact that a person only absorbs about 25 percent of the available oxygen with each breath. The exhaled air passes through a scrubbing material, such as soda lime, wherein the carbon dioxide is removed. Additional oxygen and/or a diluent is added to the circuit either manually or via an electronic system that senses for the oxygen concentration using appropriate sensors such as oxygen sensitive electro-galvanic fuels cells that calculate the oxygen concentration in the breathing loop. The scrubbing material is held within a canister that is worn about the body of the person. The breathing air within the loop moves into and out of the canister through the small pressure changes generated through respiration by the user. While extremely useful, current rebreathers suffer from certain limitations. The large mounted scrubbing canister is cumbersome to wear and throws the overall weight distribution of the wearer far off from ideal. A land-based user finds such large canisters and the uneven weight distribution occasioned by the canisters to impede maneuverability and increase overall fatigue. Water-based users find that the canisters change the natural contours of the body so as to make the user less hydrodynamic via increased drag which decreases swimming speed and also increases fatigue. If the underwater user is scooter-based, the increased profile provided by current rebreathers increases overall drag which decreases scooter performance and decreases battery life. If a water-based user transitions to land, the uneven weight loading provided by the rebreather makes the transition awkward at best. Additionally, the diver is subject to hydrostatic loads due to the extra force required to breathe into a counter-lung above or exhale into a volume below the diver's chest.
What is needed is a rebreather that addresses the above-mentioned shortcoming in the art by providing a closed circuit rebreathing system that does not rely on a large carbon dioxide scrubbing canister that affects the natural contours of the user and that does not greatly alter the overall weight distribution load upon the wearer. Such a rebreather should allow the counter-lungs used by a rebreather to be essentially at chest level in order to permit the user to breath without the need to exert substantial additional breathing pressure. Ideally, such a rebreather will be of relatively simple design and construction and be easy to use and maintain.
SUMMARY OF THE INVENTION
The rebreather vest of the present invention addresses the aforementioned needs in the art by providing a closed circuit rebreathing system that, when donned, generally maintains the natural low profile contours of the wearer so as to allow the person to maintain a high level of hydrodynamics when under water so as to allow the person to be able to achieve essentially maximum velocity while swimming without undue fatigue or to minimize drag if using a scooter so as to maintain maximum performance of the scooter without shortening battery life to any great extent. The rebreather vest distributes the weight essentially evenly about the torso of the wearer so as to make the weight distribution more natural in order to allow the user to be more maneuverable on land as well as when transitioning from water to land. The rebreather vest provides its counter lungs at torso level so as to reduce the respiration pressures that must be maintained by the user so as to minimize fatigue. The rebreather vest is of relatively simple design and construction being made using standard manufacturing techniques. The rebreather vest is designed so that it can be stored in a partial vacuum until the device is needed so as to minimize size and storage requirements.
The rebreather vest of the present invention uses a counter-lung design that allows a flow path both above and below the arm of the wearer via the flow path of least resistance. The rebreather vest employs the use of a flexible carbon dioxide removal system deployed around the torso. The rebreather vest encapsulates a miniaturized high-pressure gas source within the counter-lung and may use the form of a single-use rebreather.
The rebreather vest of the present invention is comprised of a human-torso-wearing configured vest that has a first front portion and a second front portion joined by a back portion such that an internal air tight cavity exists within the vest. The cavity is divided into a series of passageways that form a single continuous channel that passes from the first front portion through the back portion and to the second front portion. The channel has a commencement point and a termination point. The cavity may be bounded by an inner layer and an outer layer. A first inlet port is located on the first front portion of the vest at the channel commencement point while an outlet port is located on the second front portion of the vest at the channel termination point. A tube has a first end connected to the first inlet port and an opposing second end attached to the outlet port and also has an opening disposed along its length. A first check valve is disposed within the tube between the opening and the first inlet port while a second check valve is disposed within the tube between the opening and the outlet port. A carbon dioxide scrubbing material is removably disposed throughout the length of the channel. A mouthpiece, such as a T-bit mouthpiece, may be located at the opening. A second inlet port is located on the vest such that a first canister having oxygen or diluent therein is fluid flow connected to the second inlet port. A control valve may be fluid flow connected with the first canister and the internal cavity while an oxygen sensor is disposed within the internal cavity and a processing module is provided for controlling the control valve based on at least one reading provided by the oxygen sensor. The first canister may be encapsulated within the second front portion and deliver its gas through a demand regulator system. A third inlet port may be located on the vest such that a second canister having oxygen or diluent therein is fluid flow connected to the third inlet port. An anti-collapse coil maybe disposed within the internal cavity. At least one over-pressure valve is attached to an outer surface of the vest and is in fluid flow communication with the internal cavity. Mounting studs may extend outwardly from the vest. A divider having a first surface and an opposing second surface may be disposed within the internal cavity between the inner layer and the outer layer such that a first portion of the channel is disposed between the first surface of the divider and the inner layer and a second portion of the channel disposed between the second surface of the divider and the outer layer. Neither the first portion of the channel nor the second portion of the channel is necessarily contiguous. A plurality of generally V-shaped resilient spacers may each be attached to either the inner layer or to the outer layer and face toward the divider. Alternately, a plurality of ribs is provided such that each rib is attached to the first surface of the divider and to the second surface of the divider. The scrubbing material may be disposed within the channel in a first layer and an overlapping second layer separated by a fibered filter material based spacer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a is a front elevation view of the rebreather vest of the present invention in a single layer demand and/or constant flow gas injection configuration.
FIG. 1 b is a back elevation view of the rebreather vest of FIG. 1 a.
FIG. 2 is a front elevation view of the rebreather vest in a double layer demand and electronic control gas injection configuration.
FIG. 3 is a back elevation of the rebreather vest of FIG. 2 .
FIG. 4 is a perspective view of the rebreather vest of FIG. 2
FIG. 5 is a partial cross-section view of the rebreather vest of FIG. 2 .
FIG. 6 is a perspective sectioned view of a portion of the internal channels within the rebreather vest of FIG. 2 .
FIG. 7 is an end view of the rebreather vest of FIG. 5 .
FIGS. 8 and 9 are perspective views of other shapes possible for extruded carbon-dioxide absorbent material for use within the internal cavity of the rebreather vest.
Similar reference numerals refer to similar parts throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, it is seen that the rebreather vest of the present invention, generally denoted by reference numeral 10 , is comprised of a vest 12 of typical human torso configured vest configuration having a front left portion 14 that serves as a first counter-lung, a front right portion 16 that serves as a second counter-lung joined by a back portion 18 . Webbing 20 may be used to join the back portion 18 with the ends of the front portions 14 and 16 or the back portion 18 may be full. Appropriate closure mechanisms (zipper, snap, latches, etc.,—none illustrated)—can be used to close the front of the vest 12 in the usual way.
In the embodiment illustrated in FIG. 1 a , the vest 10 has a first front closure edge, right closure edge or right closure segment extending substantially parallel to, and adjacent to, the zipper at opening 38 . Likewise, the vest 10 has a second front closure edge, left closure edge or left closure segment shown, in FIG. 1 a , opposite of such right closure segment. As illustrated in FIG. 1 a , the vest 10 has a perimeter edge extending along the perimeter of the vest. The perimeter edge includes the right closure segment, left closure segment and bottom segment. The perimeter edge defines the neck receiving opening when the right closure segment is in contact with the left closure segment. The vest 10 has a right arm receiving edge which, in the embodiment illustrated in FIG. 4 , is located to the right of the outlet port 44 . The vest 10 has a left arm receiving edge which, in the embodiment illustrated in FIG. 4 , is located to the left of the outlet port 42 .
The vest 12 is formed from an inner layer 22 that contacts the user's body and an outer layer 24 joined together in order to provide an air tight internal cavity 26 within the vest 12 . In the embodiment illustrated in FIG. 4 , a plurality of seals join the layers 22 and 24 together. A first seal extends along the perimeter edge described above. A second seal extends along the right arm receiving edge described above. A third seal extends along the left arm receiving edge described above.
The inner layer 22 is made from an appropriate material for body contact which material allows for body hugging as well as stretching. Thin neoprene and Lycra are two suitable materials, although other candidates are also possible. The outer layer 24 may be the same as the inner layer and may have an additional layer 28 thereon that provides additional functionality to the vest 12 such as a ballistic material (KEVLAR etc.,) or may have pockets (not illustrated) into which appropriate body armor may be disposed. If a breathable material is used for either layer 22 and 24 , an appropriate layer will be added in order to achieve the air tight internal cavity 26 . The internal cavity 26 is segregated into a series of passages 30 by a series of walls 32 , made from an appropriate sturdy material such as flexible plastic that is attached to the inner layer 22 and the outer layer 24 . The passages 30 form a single overall continuous channel Removably attached to the inner layer 22 or outer layer 24 or both layers 22 and 24 is an appropriate carbon dioxide scrubbing material 34 such as soda lime, etc. The scrubbing material 34 is to be disposed on a separate backing material 36 (a so-called scrubbing material belt) so as to allow the scrubbing material 34 to be able to be quickly and easily removed and replaced when fully spent. An opening 38 , such as the illustrated zipper (other candidates include cooperating hook and loop material, snaps, etc.,) is provided in order to have service access to the internal cavity 26 —the opening 38 can be located at any appropriate location about the vest 12 . An appropriate seal (not illustrated) is located beyond the opening 38 in order to maintain the air tightness of the internal cavity 26 . Also disposed within the internal cavity 26 is a pair of oxygen compatible anti-collapse coils 40 that help maintain the internal cavity 26 in an “open” configuration when the device 10 is being used.
As seen a first or inlet port 42 is attached to the left portion 14 of the vest 12 and air flow communicates with the channel 30 , the channel 30 having its commencement point hereat. A second or outlet port 44 is attached to the right portion 16 of the vest 12 and air flow communicates with the channel 30 , the channel 30 having its termination point hereat. A tube 46 has a first end attached to the inlet port 42 and a second end attached to the outlet port 44 . A mouthpiece 48 , such as the illustrated T-bit mouthpiece is disposed centrally along the length of the tube 46 . It is expressly recognized that a face shield or a full head mask can be used in lieu of or in addition to the mouthpiece 48 depending on the specific application desired for the rebreather 10 as is well understood in the art. A first check valve 50 is located within the tube 46 between the mouthpiece 48 and the inlet port 42 while a second check valve 52 is located within the tube 46 between the mouthpiece 48 and the outlet port 44 . A second inlet port 54 is provided and is fluid flow connected to a first canister 56 having a first valve 58 thereon, via a first air hose 60 , the first canister 56 having oxygen or diluent therein.
As best seen in FIGS. 2-4 , the first canister 56 may also be connected via a second air hose 62 to a control valve 64 , advantageously located on the back portion 18 , the control valve 64 fluid flow connecting the second hose 62 with the internal cavity 26 . One or more oxygen sensors 66 are located on the back portion 18 within a pocket of the vest 12 and sense oxygen levels within the channel 30 . The oxygen sensors 66 are electronically connected to a processing module 68 which module 68 is also connected to the control valve 64 for controlling operation of the control valve 64 based on the readings of the sensors 66 . An appropriate display device 70 is connected to the processing module 68 in order to allow the user to monitor the status of the processing module 68 . As also seen, a third inlet port 72 may be provided and be fluid flow connected to a second canister 74 having a second valve 76 thereon, via a third air hose 78 , the second canister 74 having oxygen or diluent therein. In a two canister configuration, typically the first canister 56 has oxygen therein while the second canister 74 has diluent therein
As seen, the internal cavity 26 may be separated into two sections via a semi-rigid (sufficiently rigid to hold its shape, yet sufficiently flexible for vest 12 donning and doffing) divider 80 that extends essentially throughout the internal cavity 26 so that one section of the internal cavity 26 is located between the divider 80 and the inner layer 22 of the vest 12 and the other section is located between the divider 80 and the outer layer 24 of the vest 12 . The scrubbing material 34 is disposed on both sides of the divider 80 . In this configuration, the channel 30 is still a single continuous channel with its commencement point at the first inlet port 42 and its termination point at the outlet port 44 , but now passes through both sections of the internal cavity 26 . In this configuration, the air A passes across substantially more scrubbing material 34 allowing for longer dwell times with the scrubbing material 34 allowing more effective scrubbing of the air A as well as a longer life span between scrubbing material 34 change out.
In this dual section configuration, the vest 12 is maintained in the “open” position by a series of separators 82 that are attached to the inner layer 22 of the vest 12 as well as the outer layer 24 of the vest 12 . The separators 82 are made from an appropriate resilient material such as a flexible non-reactive plastic. When the device 10 is not being used, the vest 12 may be held flat, that is the outer layer 24 and the inner layer 22 are pressed tight together which causes the separators 82 to flatten out thereby maintaining the vest 12 is a very flat and compact configuration that is easily stored and transported. The vest 12 may be held in this very flat configuration via an appropriate mechanical means or may be stored under at least partial vacuum to so maintain the vest 12 . When the vest 12 is ready for use, either release of the vest 12 from its mechanical or vacuum hold allows the separators 82 to resiliently spring back to their original V-shape or introduction of air A into the internal cavity 26 achieves the result, thereby filling the vest 12 out. In this configuration, the separators 82 act as valves or flow restrictors for the air A passing thereby. This creates turbulence within the channel 30 which increases the interaction time between the air A and the scrubber material 34 so as to achieve greater efficiency in air scrubbing.
As also seen, a series of mounting ribs 84 may be provided and have mounting studs 86 thereon to hold auxiliary equipment E as desired.
As seen in FIGS. 7-9 , an alternate method of separating the layers of the internal cavity 26 uses a divider 80 ′ that has a series of spacer ribs 88 of any appropriate configuration (see FIGS. 8 and 9 ) on either side, either formed as part of the divider 80 ′ or attached thereto. In this configuration, once a belt of scrubber material 34 is attached to or positioned upon the spacer ribs 88 , a spacer 90 may be placed on the scrubber material 34 , such spacer 90 being a fiber air filter type of material, with a second belt of scrubber material 34 placed onto the spacer 90 in order to further increase the amount of scrubber material 34 within the internal cavity 26 .
If water should enter the internal cavity 26 in any fashion, then either a desiccant (not illustrated) can be disposed within the internal; cavity 26 or one or more dump/over-pressure valves 92 can be located on the vest 12 at substantially the lowest point on the vest 12 in order to dispel any water entrained within the internal cavity 26 .
In order to use the rebreather vest 10 of the present invention, the channel 30 is populated with the scrubbing material 34 while a fresh first canister 56 is attached to the first hose 60 and second hose 62 if so configured, and a fresh second canister 74 is attached to the third hose 78 . The user dons the vest 12 is the typical way and places the mouthpiece 48 into his or her mouth. The user breathes in normal fashion in the same manner as with other rebreathers. As the person exhales, the exhaled air A is passed through the mouthpiece 48 and enters the inlet port 42 via the tube 46 , the second check valve 52 preventing the air A from flowing toward the outlet port 44 . The air enters the channel 30 within the vest 12 and travels the length of the channel 30 through the front left portion 14 , through the back portion 18 , and into the front right portion 16 . While within the channel 30 , the air A is scrubbed via the scrubbing material 34 in the usual way. Once the air A has reached the end of the channel 30 , the air A enters the tube 46 , scrubbed of carbon dioxide, via the outlet port 44 and is breathed in by the user. During breath intake in, the user cannot draw air A from the inlet port 42 due to the first check valve 50 . By having the relatively heavy scrubbing material 34 distributed about the vest 12 , both front and back, the overall weight distribution of the rebreather 10 for the wearer is relatively well distributed and helps the user maintain balance as humans work exceedingly well whenever a load is essentially evenly placed on the user's torso. Additionally, both counter-lungs are at torso level making breathing more natural and less labored so as to reduce user fatigue during device 10 usage. Variations employ constant flow oxygen or gas mixture injection as in a semi-closed set plus conventional demand regulator gas delivery during high work output. The constant flow plus demand regulation system allows for positive pressure masks on the wearer. Land based use in contaminated atmospheres is greatly enhanced by this feature. When needed, oxygen, either pure or via a diluent, can be manually replenished into the channel 30 via the first canister 56 simply by opening the valve 58 thereon and letting the oxygen or diluent flow into the channel 30 via the second inlet port 54 or via the second canister 74 by opening the second valve 76 and letting the oxygen or diluent flow into the channel via the third inlet port 72 . Alternately, if the rebreather 10 is electronically equipped, then oxygen or diluent is introduced into the channel 30 automatically via the control valve 62 via the readings of the oxygen sensors 66 and under the control of the processing module 68 . Of course the automatic replenishment system can be manually overridden if the user so desires. When the scrubbing material 34 is fully spent, the material 34 is removed and replenished via the opening 38 provided.
While the invention has been particularly shown and described with reference to embodiments thereof, it will be appreciated by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention. | A rebreathing apparatus has a clothing article wearable on a person. The clothing article defines a channel configured to be fluidly connected to at least one tube. The tube is configured to be fluidly connected to a mouthpiece. When the person exhales, the exhaled breath enters one end of the channel and passes through the channel while being scrubbed of CO 2 . When the user inhales, the scrubbed air is drawn from the channel. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for the cutoff of a fiber material web, such as a web for paper or cardboard, in a paper machine such as a paper-making machine, rewinder, coater and/or rotary slitter.
2. Description of the Related Art
A cutoff apparatus as described above may be configured with a machinewide knife that extends transverse to the direction of paper travel (see, e.g., DE 38 15 277). The cutting edge of the knife according to DE 38 15 277 has a large distance from the impact point of the cutting edge to the splice on the splicing roll. As a result, an excessively long paper remnant, or paper tail, remains behind the splice after cutoff of the material web and gluing it to a new web. This leads to breaks, for example in a follow-on coater, notably with thin paper grades. Furthermore, the apparatus according to DE 38 15 227 has the further disadvantage that a serrated blade is used, as a result of which the web undesirably has a serrated cutoff edge.
DE-U-94 13 363 shows an apparatus for cutoff of a traveling material web. The apparatus is equipped with a cutoff knife heavily slanted opposite to the direction of web travel and avoids the latter of the aforementioned disadvantages. The angle occurring during the cutoff process between cutoff knife and material web is with the object according to DE-U-94 13 363 smaller than 45 degrees. At low web velocities, a cutoff edge which is extensively straight across the material web can be achieved with it, but, especially with high web velocities, >1500 m/min, the measures according to DE-U-94 13 363 are no longer sufficient to achieve the desired reliability of operation. A factor in addition to the known problems with the above high web velocities is that the cutoff velocity of the cutoff knife is mostly insufficient to achieve a non-serrated cutoff.
What is needed in the art is a cutoff apparatus which overcomes the disadvantages that occur at high web velocities with the prior-art apparatuses.
SUMMARY OF THE INVENTION
According to a first embodiment, the cutting edge of the knife disposed underneath the material web is in the inoperative position located in the gore between the paper web and a load roll, spaced slightly from a nip formed by the load roll and a roll. This creates the advantage that the material web remnant which after web cutoff enters the nip, e.g., a splicing nip, is very short.
The invention provides for coordinating with the cutoff knife an actuator that comprises at least one impulse exchanger. Achieved with the use of such actuator, as compared to the actuators known heretofore, is the advantage of a non-serrated cutoff at very high web velocities.
According to the invention, the impulse exchange may take place mechanically or pneumatically. The impulse exchanger produces a collision, or impulse exchange, between two masses. As is evident from the following formula for a mechanical impulse generator, it is especially advantageous for the mass of the cutoff knife to be very slight, V 2 = 2 m 1 × V 1 m 1 + m 2
where V 2 is the velocity of the cutoff knife with the mass m 2 after the collision, and V 1 is the velocity of the striking mass m 1 . With m 2 being much smaller than m 1 , all that can be achieved in the most favorable case is a cutoff knife velocity twice as high as the velocity of the striking mass.
As mentioned already above, a pneumatic impulse generator may also be employed; it uses a directional flow—for example compressed air—that is directed at the cutoff knife and accelerates it by exchange of the flow impulse.
Moreover, the acceleration of the cutoff knife can be aided when the actuator features in addition to the described impulse generators an energy store, for example a spring or store of compressed air. The energy stored in these systems is upon knife actuation released abruptly and converted to kinetic energy of the cutoff knife.
Of particular advantage is slanting the cutoff knife opposite to the direction of web travel. A preferred embodiment provides for the angle created in the cutoff process between the cutoff knife and the material web to be less than 45 degrees. The slanting of the cutoff knife shortens the cutoff times further still as compared to prior solutions, so that the material web cutoff proceeds very quickly. For example, an escape of the web and, thus, the tendency of wrinkling is nearly precluded.
Another embodiment provides for optimally adjusting to one another, with respect to a non-serrated cutoff, the factors that influence the cutoff edge, such as the angle forming during the cutoff process between the cutoff knife and the material web, the velocity of the material web and the approach velocity of the cutoff knife.
With the present invention, the cutoff knife is by impulse exchange accelerated such that the traveling material web is being cut off at a high cutoff knife velocity.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a schematic illustration of one embodiment of a cutoff apparatus of the present invention in a gore between the fiber material web and a load roll, a slight distance from a nip formed by the load roll and another roll;
FIG. 2 is a more detailed illustration of the cutoff apparatus shown in FIG. 1 :
FIG. 3 illustrates another embodiment of a cutoff apparatus of the present invention including a cutoff knife and a mechanical impulse generator as an actuator;
FIG. 4 illustrates yet another embodiment of a cutoff apparatus of the present invention including a cutoff knife and a non-mechanical impulse generator as an actuator; and
FIG. 5 illustrates still another embodiment of a cutoff apparatus of the present invention including a cutoff knife, an impulse generator and an energy store.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an embodiment of the cutoff apparatus 10 of the present invention including a cutoff knife 12 in a splicer intended for use in coaters. The splicer includes a new paper roll 1 and an old paper roll 2 from which is unwinding a depleting fiber material web in the form of a paper web 3 . In splicing the end of web 3 to the leader of new paper roll 1 , the splicer is moved toward roll 1 . A nip or splicing point 5 is created between the load roll 4 and the new paper roll 1 , where the end of the old web 3 is glued to the leader of the new web from new paper roll 1 . Disposed on the approach side and directly before load roll 4 is a cutoff apparatus 10 , which in the present case is equipped with a cutoff knife 12 and an impulse exchanger 11 . The cutoff knife 12 has a cutting edge 13 that is slanted opposite to the direction of web travel. This arrangement of the cutoff apparatus 10 in the gore between roll 1 and load roll 4 , spaced slightly relative to the splicing point 5 , achieves that the old paper web remnant entering the nip upon cutoff of the paper web 3 is only short.
Owing to the illustrated design of the cutoff apparatus, moreover, the cutoff operation does not cause a liftoff of the web, thereby avoiding with the present invention the web stabilizers, such as suction boxes arranged in prior-art designs before the splice.
FIG. 2 shows the inventional apparatus relative to FIG. 1 in more detail. Similar to the arrangement according to FIG. 1, the cutoff apparatus 10 is disposed in the gore underneath the paper web 3 near the load roll 4 . Cutoff knife 12 includes a cutting edge 13 which is slanted opposite to the direction of web travel and mounted in a clamp 14 . The part of cutoff knife 12 that is not clamped in place is movable in vertical direction under the effect of bending forces. Clamp 14 is secured to a support arm 15 of cutoff apparatus 10 . Below clamp 14 , a mechanical impulse generator 17 is mounted pivotably on the support arm 15 in a bearing 16 . The mechanical impulse generator 17 mounted pivotably, or rotatably, in the bearing 16 is retained elastically, by clamping effect, between the underside of clamp 14 and a prop 18 , by means of two deformable elements, for example, elastic compressed-air hoses 19 and 20 . When now inflating the lower compressed-air hose 19 and deflating the upper compressed-air hose 20 , the mechanical impulse generator 17 pivots about the axis of bearing 16 and makes contact with the bottom edge of the cutoff knife 12 . In the process, an impulse exchange takes place from the mechanical impulse generator to the cutoff knife. The mounted cutoff knife 12 accelerates toward the paper web and cuts it off. The knife 12 being clamped in the clamp 14 , it retracts to the illustrated starting position under the recoil force that results from the clamping of the blade. A stop 52 prevents the knife from overshooting in the direction of the mechanical impulse generator 17 . In splicing the old web to the new one, the splicing or load roll 4 is located in the deployed splicing position 4 ′ depicted.
Further embodiments of a mechanical impulse generator (refer to FIG. 3) and of a pneumatic impulse generator are illustrated schematically in FIGS. 4 and 5. According to FIG. 3, the cutoff knife 12 is mounted rotatably in a massive bearing block 21 . Massive bearing block 21 includes a round bearing bore 22 that receives the bearing 16 of the cutoff knife 12 . Bordering on the bearing bore 22 is a V-shaped recess 23 formed in bearing block 21 . In its inoperative position, knife 12 rests on the bottom edge 24 of V-shaped recess 23 . Mounted on the massive bearing block 21 , by means of a holder 25 , is a mechanical impulse generator 26 . Mechanical impulse generator 26 includes, e.g., a cylinder assembly 27 , which can be operated by compressed air or hydraulics and includes a plunger 28 of a mass m 1 , attached to a plunger rod 29 fitted in cylinder assembly 27 . When actuating cutoff knife 12 , cylinder assembly 27 is actuated out of its illustrated inoperative position, and the mass m 1 of plunger 28 accelerates to the velocity V 1 , at which it impinges at point 30 on the inoperative, rotatably mounted cutoff knife.
The preferably dead jolt transfers the impulse of mass m 1 virtually entirely to the movable mass of cutoff knife 12 having a mass m 2 which is accelerated to a velocity V 2 and moves about the bearing axis to the dashed position, cutting the paper web 3 off in the process. The rotary motion of cutoff knife 12 is limited by the top edge 31 of V-shaped recess 23 . With the paper web 3 cut off, the cutoff knife 12 proceeds by reset forces, e,g., by gravity, to its starting position, in which the cutoff knife rests on the bottom edge 24 of V-shaped recess 23 , and the plunger 28 retracts to its indicated starting, or inoperative position.
FIG. 4 shows another exemplary embodiment of an inventional cutoff knife with a pneumatic impulse generator. As in the case of FIG. 3, the cutoff knife 12 is mounted rotatably in a bearing 22 in a massive bearing block 21 . The same as in FIG. 3, bearing block 21 has a V-shaped recess 23 . Several orifices 40 of a nozzle assembly are arranged successively in the underside 24 the V-shaped recess 23 in the bearing block 21 . Orifices 40 connect via ducts 41 to a pressure chamber 43 provided in the bearing block 21 , in which chamber rests a compressed-air hose 42 . In its inoperative position, cutoff knife 12 bears on bottom edge 24 of V-shaped recess 23 . In actuating the knife, compressed air released from compressed-air hose 42 flows from the compressed-air chamber 43 through duct 41 to the orifices 40 . The impulse carried along by the flow actuates the cutoff knife 12 and accelerates it to a velocity V 2 , thereby cutting the paper web 3 off. The rotary motion of knife 12 is limited by the top edge 31 of the V-shaped recess 23 , the same as in FIG. 3 .
Instead of using a compressed-air hose 42 , valves (not illustrated in FIG. 4) may initiate the flow out of the compressed-air chamber 43 . To that end, the valves are suitably integrated in the ducts 41 .
In accordance with the embodiment illustrated in FIG. 5, it is optionally also possible to combine an energy storage apparatus, or energy storage system, with an impulse exchanger according to, e.g., FIG. 3 or FIG. 4 . According to FIG. 5, a spring 50 serves as an energy store. Conceivable would be also other energy stores, such as inflated elastic compressed-air hoses. Spring 50 is in a compressed state when the cutoff knife, as illustrated, assumes its inoperative position. In order for cutoff knife 12 not to be actuated unintendedly by the energy stored in the spring, cutoff knife 12 is fixed in the illustrated position by a holddown 51 . Upon release of holddown 51 , cutoff knife 12 is in synchronism acted upon by a flow impulse while the holddown 51 pivots to the position shown by a dashed line, thereby abruptly releasing the energy stored in spring 50 and accelerating cutoff knife 12 in addition to the impulse exchange from orifices 40 .
The present invention thus makes it for the first time possible to achieve also in the case of material webs traveling at high speed a flawless cutoff the of the paper web, thereby preventing difficulties in subsequent processing, for example, in a splicer or coater. | A paper machine for one of making and processing a fiber material web. A plurality of rolls carry the fiber material web. The plurality of rolls include a load roll and another roll defining a nip therebetween. The fiber material web travels through the nip and defines a gore with the load roll on an approach side of the nip. A movable cutoff knife includes a cutting edge positioned in the gore at a slight distance from the nip and adjacent to the fiber material web. At least one impulse exchanger is positioned in association with the cutoff knife. The impulse exchanger is configured to transfer impulse energy to the cutoff knife whereby the cutting edge cuts the fiber material web. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to hydrogenation reactions, more particularly, to a method for preparing dimethyl 1,4-cyclohexanedicarboxlate (DMCD) by a hydrogenation reaction.
[0003] 2. Description of Related Art
[0004] 1,4-cyclohexanedimethanol (CHDM) is widely used for condensing monomers of a polymer and a unique polyester. DMCD is an intermediate during the synthesis of CHDM, and plays an important role in the synthesis of CHDM.
[0005] Usually, the preparation of DMCD involves the use of dimethyl terephthalate (DMT) as a starting material, and then two different types of hydrogenation reactions sequentially take place (i.e., the hydrogenation of a benzene backbone and the hydrogenation of an ester). The hydrogenation of the benzene backbone of DMT generates DMCD, and then the hydrogenation of the ester of DMCD generates CHDM.
[0006] The hydrogenation catalysts added in the above two steps are different, wherein the catalysts used as the hydrogenation catalysts for a benzene backbone have gradually progressed from the earlier used palladium-based catalysts to the current ruthenium-based catalysts. When a palladium-based catalyst is used, a higher pressure and a higher temperature (e.g., from 140 to 400° C.) are required. Further, the palladium-based catalyst is likely to be poisoned by CO as a by-product of the reaction. On the contrary, a ruthenium-based catalyst can react at a lower pressure (e.g., from 10 to 175 bars) and a lower temperature range (e.g., from 150 to 230° C.), and is not poisoned by the CO by-product. However, the ruthenium-based catalyst is likely to be inactivated, leading to shorter lifetime and lower yield.
[0007] U.S. Pat. No. 3,334,149 firstly discloses a palladium-based catalyst, which requires a pressure of 340 bars. Subsequently, CN1099382 discloses the control of the palladium content, dispersibility, depth of the surface, and the crystalline phase of Al 2 O 3 in a Pd/Al 2 O 3 catalyst lowers the reaction pressure to 125 bars.
[0008] Moreover, it has been reported that a metal of group VIIIB or IIA is added as a second component or a metal selected from group VIIIB, Ti 4+ , Zr 4+ , Sn 4+ , Mn 4+ and Cr 4+ is added as a third component to increase activity of hydrogenation. CN1099745 discloses that a metal of group VIIIB, such as one of Ni, Ru and Pt, is added as a second component to increase the activity of hydrogenation, and can lower the reaction pressure to 125 bars. CN102381976 discloses that the addition of a catalyst with magnesium (Mg) as a second component, and one or more tetravalent metals (M 4+ ) selected from Ti 4+ , Zr 4+ , Sn 4+ , Mn 4+ and Cr 4+ as a third component can lower the reaction temperature to 70 bars.
[0009] U.S. Pat. No. 3,334,149 firstly discloses a ruthenium-based catalyst. The catalyst is Ru/Al 2 O 3 , and can catalyze hydrogenation at 160° C. and 50 bars. TW565469 discloses the use of different catalysts for hydrogenation reactions in a method can increase the reaction activity, and carries out the hydrogenation reactions at pressures of from 48.26 to 55.1 bars. CN102796001 discloses that hydrogenation can take place at 40 bars by using DMCD as a solvent. CN1689698 discloses that hydrogenation can take place at 40 bars by using Si as a first auxiliary and Ru as a second auxiliary. CN1915962 discloses that hydrogenation reactions can take place as batches at 30 bars by altering the metal contents and using a solvent.
[0010] The above patents show that if a palladium-based catalyst is used during the process of generating DMCD from DMT, hydrogenation reactions need to take place in a high pressure environment. The buildup cost and operational fee of a factory for the reactions are very high. By the use of a ruthenium-based catalyst, the reaction pressure and the production cost are reduced at the same time. However, a continuous hydrogenation reaction cannot take place at a pressure of lower than 40 bars.
[0011] Accordingly, there still exists a need to develop a method for preparing DMCD by a continuous hydrogenation reaction at a lower pressure.
SUMMARY OF THE INVENTION
[0012] The present invention provides a method for preparing DMCD, including hydrogenating DMT in a reactor containing a Ru/Al 2 O 3 catalyst to prepare the DMCD, wherein the pressure in the reactor is from 20 to 30 kg/cm 2 (i.e., from 9.81 to 29.43 bars), and the liquid hourly space velocity (LHSV) of the DMT is from 2 to 8 hours −1 .
[0013] The present invention further provides a method for preparing CHDM, including hydrogenating DMT in a first reactor containing a Ru/Al 2 O 3 catalyst to continuously form DMCD, wherein the pressure in the first reactor is from 20 to 30 kg/cm 2 , and the LHSV of DMT is from 2 to 8 hours −1 ; and charging the DMCD into a second reactor to hydrogenate an ester group of the DMCD.
[0014] The present invention employs a ruthenium catalyst as an active component, instead of the more expensive rare palladium metal. At the same time, the technical bottleneck of not being able to perform continuous hydrogenation at a pressure lower than 40 bars in the state-of-art can be overcome. As such, the safety can be significantly increased and the operational fee can be saved, and thereby bringing about economical benefits in the industrial standard. In addition, the method of the present invention is still able to achieve a high conversion rate of DMT and high DMCD selectivity even under a low pressure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The following specific embodiments are used to illustrate the detailed description of the present invention, but the claims of the present invention are not restricted thereto. The present invention can also be implemented or applied by other different ways. Each of the details in the present specification can be modified or altered in any way based on different aspects and applications, without departing from the spirit of the disclosure of the present invention.
[0016] The present invention provides a method for preparing DMCD, including hydrogenating DMT in a reactor containing a Ru/Al 2 O 3 catalyst to continuously prepare the DMCD, wherein the pressure in the reactor is from 20 to 30 kg/cm 2 (i.e., from 9.81 to 29.43 bars), and the liquid hourly space velocity (LHSV) of DMT is from 2 to 8 hours −1 .
[0017] In the preparation of DMCD, the reactor can be either a batch reactor or a continuous reactor, depending upon the operation. The batch reactor refers a reactor used for charging once before a reaction, and discharging once after the completion of the reaction. The continuous reactor refers to a reactor used for continuously charging, continuously reacting, and continuously discharging.
[0018] In the present invention, a trickle bed reactor (which is a tri-phase reactor) is used, particularly a type of reactor in which a granular solid catalyst bed through which gas and liquid move in a cocurrent flow for a tri-phase reaction of gas, liquid and solid is used. The reactor has the advantages of being a simple structure and having a low equipment cost and the feature of allowing an easy and flexible operation. Therefore, the trickle fluid bed reactor has a wide range of applications in the fields of oil refining and chemical engineering. In particular, the trickle fluid bed reactor is one of the most basic reactors used in the fields of cracking oil products by hydrogenation and refining hydrocarbons by hydrogenation.
[0019] If reactors are distinguished by the approach for delivering reaction materials, they can be classified into fixed-bed reactors and fluidized-bed reactors. Fixed-bed reactors are also referred to as packed bed reactors, each of which is packed with a solid catalyst or a solid reactant, and used as a reactor for carrying out a multi-phase reaction. A solid is usually granular, and has a particle diameter of from about 2 to 15 mm The solids stack to form a bed with a certain height (or thickness). The bed is immobile, and a fluid passes through the bed for a reaction to take place. The fluidized-bed reactor is distinguished from the fixed-bed reactor in that the solid particles are not immobile.
[0020] The catalysts in a fluidized-bed reactor are not limited to be granular. Mesh catalysts have already been applied industrially. Currently, honeycomb and fibrous catalysts have also been widely used.
[0021] The catalysts in a trickle bed reactor can exist in the form of a fixed bed. Thus, this type of reactor can also be regarded as a type of a fluidized-bed reactor.
[0022] In an embodiment of the method for preparing DMCD, the reactor is a fixed-bed reactor.
[0023] Usually, in the method for preparing DMCD, DMT is dissolved in a solvent. The solvent can be methyl acetate, ethyl acetate, propyl acetate, butyl acetate, or at least one selected from the group consisting of the foregoing. In an example, the solvent is ethyl acetate.
[0024] In another embodiment of the method for preparing DMCD, the reaction temperature of hydrogenation is lower than 230° C. The temperature of hydrogenation is usually from 100 to 180° C., preferably from 120 to 160° C. Specifically, in a fixed-bed reactor containing a Ru/Al 2 O 3 catalyst, DMT is hydrogenated at a temperature of from 100 to 180° C. or from 120 to 160° C.
[0025] In an example, the LHSV of DMT is from 2 to 8 hours −1 .
[0026] Moreover, according to the aforesaid method, a method for preparing CHDM is further provided, which includes hydrogenating DMT in a first reactor containing a Ru/Al 2 O 3 catalyst to continuously form DMCD, wherein the pressure in the first reactor is from 20 to 30 kg/cm 2 ; and charging the DMCD into a second reactor to hydrogenate an ester group of the DMCD.
[0027] The second reactor can also be a fixed-bed reactor. Further, in the second hydrogenation reaction, the catalyst used can be a copper catalyst having a manganese co-catalyst, the molar ratio of a hydrogen gas to a reactant can be from 200:1 to 1000:1. Relevant conditions can be referred to the content of CN1109859.
[0028] In the following examples, LHSV, conversion rate of DMT and selectivity of DMCD are defined as follows.
LHSV=DMT (mL/h)/catalyst (mL) Conversion rate of DMT=number of moles of DMT consumed/number of moles of DMT added×100% Selectivity of DMCD=number of moles of DMCD generated/number of moles of DMT consumed×100%
[0032] In the following examples, the DMT used was purchased from Acros Company, and ethyl acetate (EA) is purchased from ECHO Company.
Example 1
[0033] DMT was continuously hydrogenated to generate DMCD.
[0034] Firstly, a Ru/Al 2 O 3 globular catalyst (the weight of the packed catalyst was 78 g, and the volume of the catalyst was 57.51 mL) containing 1.5 wt % of Ru was added to a fixed-bed reactor. A mixed solution of DMT and EA and hydrogen gas were charged separately into the upper portion of the reactor. The reaction took place under the conditions of a pressure of 10 kg/cm 2 , a reaction temperature of 140° C., a flow speed of hydrogen gas of 300 ccm, a concentration of DMT of 3.5 wt % in the charged mixed solution of DMT and EA, and LHSV=2 h −1 . Upon completion of the reaction, the product was discharged from the lower portion of the reactor. The conversion rate of DMT was 64.6%, and the selectivity of DMCD was 92.8%.
Example 2
[0035] Hydrogenation was carried out under the conditions in example 1 to produce DMCD. However, the difference between examples 1 and 2 was that the pressure was increased to 20 kg/cm 2 in example 2. Upon completion of the reaction, the product was discharged from the bottom of the reactor. The conversion rate of DMT was 99.9%, and the selectivity of DMCD was 99.9%.
Example 3
[0036] Hydrogenation was carried out under the conditions in example 1 to produce DMCD. However, the difference between examples 1 and 3 was that the pressure was increased to 30 kg/cm 2 in example 3. Upon completion of the reaction, the product was discharged from the bottom of the reactor. The conversion rate of DMT was 100.0%, and the selectivity of DMCD was 100.0%.
Example 4
[0037] Hydrogenation was carried out under the conditions in example 1 to produce DMCD. However, the difference between examples 1 and 4 was that the pressure was increased to 40 kg/cm 2 in example 4. Upon completion of the reaction, the product was discharged from the bottom of the reactor. The conversion rate of DMT was 100.0%, and the selectivity of DMCD was 97.3%.
Example 5
[0038] Hydrogenation was carried out under the conditions in example 1 to produce DMCD. However, the differences between examples 1 and 5 are that the pressure were increased to 20 kg/cm 2 and the reaction temperature was decreased to 120° C. in example 5. Upon completion of the reaction, the product was discharged from the bottom of the reactor. The conversion rate of DMT was 94.8%, and the selectivity of DMCD was 100.0%.
Example 6
[0039] Hydrogenation was carried out under the conditions in example 1 to produce DMCD. However, the differences between examples 1 and 6 were that the pressure was increased to 20 kg/cm 2 and the reaction temperature was increased to 180° C. in example 6. Upon completion of the reaction, the product was discharged from the bottom of the reactor. The conversion rate of DMT was 100.0%, and the selectivity of DMCD was 97.3%.
Example 7
[0040] Hydrogenation was carried out under the conditions in example 1 to produce DMCD. However, the differences between examples 1 and 7 were that the pressure was increased to 20 kg/cm 2 and the LHSV was increased to 8 h −1 in example 7. Upon completion of the reaction, the product was discharged from the bottom of the reactor. The conversion rate of DMT was 98.3%, and the selectivity of DMCD was 99.6%.
[0041] The present invention employs a ruthenium catalyst as an active component, instead of the more expensive rare palladium metal. At the same time, the technical bottleneck of not being able to perform continuous hydrogenation at a pressure lower than 40 bars in the state-of-art can be overcome. As such, the safety can be significantly increased and the operational fee can be saved, and thereby bringing about economical benefits in the industrial standard. In addition, the method of the present invention is still able to achieve a high conversion rate of DMT and high DMCD selectivity even under a low pressure.
[0042] The above examples are provided only to illustrate the principle and effect of the present invention, and they do not limit the scope of the present invention. One skilled in the art should understand that, modifications and alterations can be made to the above examples, without departing from the spirit and scope of the present invention. Therefore, the scopes of the present disclosure should be accorded to the disclosure of the appended claims. | A method for preparing dimethyl 1,4-cyclohexanedicarboxylate (DMCD) is provided. The method includes hydrogenating dimethyl terephthalate (DMT) under a condition of a pressure of 20 to 30 kg/cm 2 to continuously prepare the DMCD, and thereby increasing the selectivity of the DMCD. A method for preparing 1,4-cyclohexanedimethanol (CHDM) is further provided. | 2 |
CROSS-REFERENCE TO CORRESPONDING APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 13/374,040 filed Dec. 8, 2011 which, in turn, is a continuation-in-part of application Ser. No. 12/592,825 filed Dec. 3, 2009 which, in turn, is a continuation-in-part of application Ser. No. 12/283,472 filed Sep. 12, 2008 which, in turn, is a continuation-in-part of application Ser. No. 12/082,576 filed Apr. 11, 2008.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a lithium silicate glass ceramic material and a process for fabricating that material for the manufacture of machinable blocks and subsequent fabrication of single crowns with the aid of a CAD/CAM device. The invention relates to a new version of such glass ceramic containing only lithium silicate as a main crystalline phase.
[0004] 2. Background Art
[0005] There are many products available that employ lithium disilicate glass ceramic covered by several U.S. patents. Some of these patents claim a process for the preparation of shaped translucent lithium disilicate glass ceramic products from a mixture of basic components (SiO 2 , Al 2 O 3 , K 2 O, Li 2 O, plus pigments and fluorescent oxides). The thermodynamic solid-liquid equilibrium of the system consisting of lithium oxide (Li 2 O) and silicon dioxide (SiO 2 ) has been extensively studied even before that material was used as a dental ceramic (1-3, 5-6).
[0006] For those skilled in the art this experimental solid-liquid equilibrium can help explain how different glass ceramics can be obtained using the same two components when they are combined in different proportions. The same solid-liquid equilibrium shows what type of stable crystal is produced as a final product of crystallization when a specific mix composition of the two components is blended, melted, and crystallized to achieve the final product.
[0007] The crystallographic data for intermediate crystal compounds in the Li 2 O—SiO 2 system is given by the Landolt-Borntein tables (4). The following are the types of crystal compositions possible in the Li 2 O—SiO 2 system: Li 8 SiO 6 , Li 4 SiO 4 or lithium orthosilicate monoclinic and orthorhombic; Li 6 Si 2 O 7 , Li 2 SiO 3 or lithium silicate; Li 2 Si 2 O or lithium disilicate monoclinic and orthorhombic; and Li 2 Si 3 O 7 lithium trisilicate. Every crystal phase is formed based upon the initial molar ratio between the two components which can be 4, 3, 2 or 1 and any combination in between.
[0008] Thus when the silicon dioxide to lithium oxide molar ratio (SiO 2 /Li 2 O) is greater than or equal to two, meaning two moles of SiO 2 are mixed with one mole of Li 2 O, the crystallized glass ceramic product will be mainly lithium disilicate (2SiO 2 .Li 2 O). This molar ratio of two is equivalent to a molar composition of lithium oxide in the binary mixture of 33% or 67% as SiO 2 . When the same molar ratio is below 2.0, (i.e. 1.7) only lithium silicate crystals are produced (Li 2 O.SiO 2 ). The lithium oxide molar composition for a ratio of 1.7 is equivalent to 37% molar or 63% as SiO 2 . The type of resulting crystal due to the specific composition ratios gives to the glass ceramic its own distinguishable chemical and physical properties. Surprisingly, the same behavior is obtained if these two main components (silicon dioxide and lithium oxide) maintain their molar ratio below two even if they are mixed with other oxides as additives and modifiers. Such other common oxides are aluminum oxide, potassium oxide, calcium oxide, zirconium oxide and coloring oxides that are incorporated into the glass matrix and give the glass ceramic its final color and translucency.
[0009] Due to the final composition of this invention using a molar ratio of SiO 2 /Li 2 O between 1.7 to 1.9, the only phase present is lithium silicate, instead of lithium disilicate, as a main constituent of the glass ceramic as a final product. This lithium silicate (Li 2 O.SiO 2 ) in this composition is thermodynamically stable meaning that it does not suffer any change in its stoichiometric compositor through the entire process. Once it is formed the only change suffered is the increase in size of the crystals at the end of the process. That means that there is no formation of any metastable lithium metasilicate which is converted to a lithium disilicate (2SiO 2 .Li 2 O) when the molar ratio (SiO 2 /Li 2 O) of the formulation is higher or equal to 2. For example, a glass ceramic with a molar ratio of silicon dioxide to lithium oxide greater than or equal to two plus additional oxides will produce, after full crystallization a lithium disilicate glass ceramic with a melting temperature of 920° C. and a linear thermal coefficient of expansion of 10.5×10 −6 /° C. as a final product and composition. In addition, during the production of this type of glass ceramic, the cast material is subjected to at least three different heat treatments: an annealing cycle for eliminating accumulated stresses, a nucleation cycle for the formation of lithium metasilicate or unstable lithium silicate, and finally a third thermal cycle to convert the unstable lithium silicate or metasilicate into a stable lithium disilicate. This complex mechanism is clearly shown in the following US patents:
[0010] Examples of those types of glass ceramics are claimed in Barret et al in U.S. Pat. No. 4,189,325 which discloses a lithium silicate glass ceramic where the raw materials are blended, melted at 1315° C. and held for 24 hours for homogenization, fritted and crushed, melted again and cast into preheated molds. They disclose a composition of silicon dioxide to lithium oxide molar ratio of two, producing a dental ceramic composed of lithium disilicate.
[0011] U.S. Pat. No. 4,480,044 to McAlinn discloses a glass ceramic formulation where the lithium silicate glass ceramic in their intermediate process stage has a thermal expansion of 13×10 −6 /° C. and the lithium disilicate has a thermal expansion of 11.4×110 −6 /° C. They disclose a machinable lithium disilicate glass ceramic with a percentage of silicon dioxide of 79.8%.
[0012] U.S. Pat. No. 4,515,634 to Wu et at discloses a castable glass ceramic composition useful as a dental restorative material. The components are blended and melted at 1400 to 1450° C., then quenched in water, dried, milled to a powder, and melted again at 1400° C. for 4 hours. Then the melt is cast into copper molds and transferred to the annealing process. The castable glass ceramic is lithium disilicate with a silicon dioxide to lithium oxide molar ratio of two, equivalent to silicon dioxide weight composition of 65%-74.7% and lithium oxide weight composition of 14.8-16.4%.
[0013] U.S. Pat. No. 5,219,799 to Beall et at discloses a lithium disilicate glass ceramic with silicon dioxide weight composition of 65%-80% and lithium oxide compositions of 8.0-19.0%. The blended raw materials are melted at 1450° C. for 16 hours and then poured into steel molds and annealed at 450° C.
[0014] U.S. Pat. No. 5,744,208 to Beall et at describes a lithium disilicate glass ceramic with silicon dioxide weight composition of 75%-95% and lithium oxide weight composition of 3-15%. The raw materials are blended, and then melted in the range of 1450-1600° C. for about 6-10 hours. The glass is then poured into steel molds. The glass is then annealed, nucleated and crystallized to produce lithium disilicate glass ceramic in the range of 500° C. to 850° C.
[0015] U.S. Pat. No. 5,968,856 to Scheweiger et al discloses a lithium disilicate glass ceramic with compositions of silicon dioxide weight between 57%-80% and lithium oxide composition 11-19%. The components are blended and melted at 1500° C. for one hour and then quenched, dried, milled, dry pressed and sintered to form blanks. The composition requires the addition of lanthanum oxide to improve the flow properties, control the crystal growth and eliminate the strong reaction of the material with the investment material used.
[0016] U.S. Pat. No. 6,514,893 to Scheweiger et al discloses a lithium disilicate glass ceramic with silicon dioxide composition of 57%-75% weight and lithium oxide composition 13-19% weight and also containing lanthanum oxide. The components are blended and fused into granulates and comminuted to a powder. Coloring oxides are then added, and the ceramic is pressed and heat treated.
[0017] U.S. Pat. No. 6,455,451 to Brodkin et al discloses a lithium disilicate glass ceramic with silicon dioxide composition of 62%-85% weight and lithium oxide composition 8-19% weight. They disclose a method of making the lithium disilicate by melting the components at 1200 to 1600° C., followed by quenching, drying, and heat treating to form the glass ceramic, followed by comminuting to a powder, compacting and sintering to a blank and pressing to form the restoration.
[0018] U.S. Pat. No. 6,517,623 to Brodkin et al discloses a pressable lithium disilicate glass ceramic where the components are melted in the range of 1200 to 1600° C., quenched, heat treated, comminuting the glass ceramic to a powder, and then compacting the powder to a starting blank before sintering the blank or the restoration.
[0019] U.S. Pat. No. 6,606,884 to Scheweiger et al describes a lithium disilicate glass ceramic where the components are mixed and melted at 1200 to 1650° C., followed by pouring the glass into water, milling and compacting, and placing the blank in a heat treatment to sinter.
[0020] U.S. Pat. No. 6,802,894 to Brodkin et al discloses a lithium disilicate glass ceramic with a silicon dioxide weight composition of 62%-85% and lithium oxide weight composition 8-19%. The components are mixed, melted at 1200 to 1600° C., and cast. The resulting glass is annealed at a range of 300 to 600° C., followed by subjecting the glass to a heat treatment from 400 to 1100° C.
[0021] U.S. Pat. No. 6,818,753 to Petticrew discloses a lithium disilicate glass ceramic with a silicon dioxide composition of 60%-80% weight and lithium oxide composition of 8-17% weight. The components are blended, melted, quenched, heat treated, milled to a powder, dry pressed, and hot pressed into the desired restoration.
[0022] Scheweiger et al U.S. Pat. No. 7,316,740 B2 claims a lithium silicate glass ceramic with silicon dioxide weight compositions of 64 to 73% and lithium oxide weight compositions of 13 to 17%. The lithium disilicate final product is demonstrated by means of a XRD pattern ( FIG. 6 ) and DSC phase transformation curve from lithium metasilicate to lithium disilicate ( FIG. 2 ). The DSC diagram shows the change in energy from the stage of metasilicate to disilicate, which is only necessary if lithium disilicate is desired to be the crystal phase used as a final product.
[0023] U.S. Pat. No. 7,452,836 to Apel et al discloses a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight producing lithium disilicate as a final product. They also describe a glass ceramic with a molar ratio of silicon dioxide to lithium oxide of at least 2.3.
[0024] U.S. Pat. No. 7,867,930 to Apel et al shows a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight producing lithium disilicate as a final product.
[0025] U.S. Pat. No. 7,871,948 to Apel et al describes a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight, producing lithium disilicate as a final product. The glass of the starting material is subjected to an initial heat treatment to form lithium metasilicate or unstable lithium silicate and then goes through a second heat treatment to convert the lithium metasilicate to a lithium disilicate.
[0026] U.S. Pat. No. 7,867,931 to Apel et al discloses a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight producing lithium disilicate as the final product. They also describe a glass ceramic with a molar ratio of silicon dioxide to lithium oxide in the range of 2.3 to 2.5.
[0027] U.S. Pat. No. 8,042,358 to Schweiger et al discloses a lithium silicate glass ceramic with silicon dioxide composition of 65%-70% weight and lithium oxide composition of 14-16% weight producing lithium disilicate as the final product. In their specific process the raw materials such as carbonates, oxides and phosphates are prepared and melted in the range of 1300-1600° C. for 2 to 10 hours. They explain that in order to obtain a particularly high degree of homogeneity, the glass melt obtained may be poured into water to form glass granulates and the glass granulates obtained are melted again.
[0028] U.S. Pat. No. 7,816,291 to Schwinger et al, discloses a lithium silicate dental glass ceramic where the starting glass uses a very specific composition and a specific process to provide in the intermediate stage a glass ceramic which consists of metastable lithium metasilicate. Then after machining the metastable lithium metasilicate, it is converted by two heat treatments into a lithium disilicate glass ceramic product with outstanding mechanical properties, excellent optical properties and very good chemical stability thereby undergoing only a very limited shrinkage. The metastable phase definition is broadly accepted by those skilled in the art as a thermodynamic unstable crystalline phase of lithium metasilicate which, when heated, disappears to allow the formation of a thermodynamic stable crystal phase form such as lithium disilicate. This is only possible for the specific composition used in this and all the prior art mentioned above.
[0029] For those skilled in the art it is well understood that the lithium oxide and silicon dioxide binary system has been extensively studied and several patents for dental glass ceramics have been granted in the last few years. However all the research so far falls in a range where lithium disilicate is formed as a final product and none of the references cited above discloses a lithium silicate glass ceramic as a final product. For those skilled in the art it is evident that the type of crystal produced depends exclusively on the molar ratio of silicon dioxide to lithium oxide in the glass ceramic and not the additives or modifiers added to the mixture. This molar ratio controls the type of crystal formed in the final composition and furthermore gives its name to the final glass ceramic.
[0030] More surprisingly, in the present invention and due to our specific formulation, there is no metastable lithium metasilicate in the intermediate stage or in the stage where the material can be easily machined into the shape of dental restorations. Instead a lithium silicate crystal which is thermodynamically stable is formed, keeping its stoichiometric composition through the entire process and therefore only grown as lithium silicate during the final stage of the process. As consequence no lithium disilicate is formed in the final stage of the process.
[0031] Most of the existing patents in the dental field describe the use the same basic components. The present invention uses germanium dioxide as a fundamental part of the formula. This oxide is broadly used in glass preparation for its good optical properties. The oxide has been well studied and has positive effects compared to common silicon glasses. It has been found that the addition of germanium oxide produces a melt with low viscosity, which facilitates the castability of the process and increases the thermal expansion and the refractive index of the resulting lithium silicate glass ceramic. More importantly, the addition of germanium dioxide increases the final density of the glass resulting in higher values of flexural strength than the lithium disilicate glasses free of germanium dioxide. U.S. Patent Application Publication No. 2004/0197738 to Ban et al discloses a process to make dental frame of zirconium-yttrium sintered ceramics and they describe dental porcelain with germanium oxide as a joint component different than the zirconium yttrium oxide frame. However germanium oxide is not used as a component of the framework ceramic network. It is used only in formulation of the ceramic joint and is just a part of a series of other oxides that can be joined to the framework material.
[0032] Due to the low silicon dioxide to lithium oxide molar ratio of 1.7 of the present invention, equivalent to 37% molar of lithium oxide (63% as silicon dioxide) the ceramic has a lower melting point compared to the glass ceramic of the prior art. In addition, this new glass ceramic contains the lowest silicon dioxide weight percent compared to all of the noted prior art. Therefore, due to this specific composition of lithium oxide in the mixture, the type of resulting crystal after crystallization (lithium silicate) gives to the glass ceramic its own chemical and physical properties, which makes it completely distinguishable from the prior glass ceramics noted above. Due to this distinguishable composition, the glass ceramic of the present invention, has a lower melting temperature which can be made even lower with the addition of germanium oxide. Germanium oxide replaces silicon dioxide in the glass network, causing it to have a negative effect on the resulting melting point compared to a glass ceramic containing only silicon dioxide. Thus the processing and optimal melting temperature is in the range of 1100° C. to 1200° C. instead of 1200° C. to 1650° C. of the U.S. patents cited above and specifically compared to U.S. Pat. No. 6,514,893 to Schweiger et al. The glass ceramics mentioned in the prior art patents cannot be cast in the range of 1100° C. to 1200° C. because they are too viscous due to their high silicon dioxide content therefore the processes disclosed in prior art patents with higher melting temperatures should be used. The present process will result in a more economical production because the energy employed for melting the glass is considerably lower and there are lower energy loses by radiation compared to the Schweiger process.
[0033] In addition to having a process with lower energy consumption, another significant improvement of the inventive process is related to the mixing and reaction of the components. In all of the cited prior art patents, the mix of the components is blended and melted at 1400 to 1650° C. and then cast or quenched in water. The quenched glass powder is dried, milled, and melted again in order to improve the homogeneity and the quality of the product. Surprisingly, we found that the first melting and casting process can be avoided if we perform a calcination process on the mixture of raw materials to a temperature in the range of 700 to 800° C. without melting the components. At this stage, all the raw materials in the form of salts (such as lithium carbonate as the source of lithium oxide, calcium carbonate as the source of calcium oxide, and di-ammonium phosphate as the source of phosphorous oxide) are decomposed, eliminating gases such carbon dioxide and ammonia, producing a ceramic powder free of gases. After cooling down, the calcined mix is milled again, producing a homogeneous powder with a very small particle size. The final step is melting and casting in the range of 1100° C. to 1200° C., resulting in a homogeneity of all the components. In addition, by eliminating the gases during the calcination process, the cast glass becomes bubble free, making this a significant advantage over the processes described in the prior art
[0034] The present invention is also unique compared to those in the prior art due to its composition. The use of a low melting temperature is only possible with the inventive glass ceramic because of the low content of silicon dioxide and the high content of lithium oxide. This translates to a molar oxide ratio (SiO 2 /Li 2 O) below 2.0, (i.e., 1.7) in which only lithium silicate crystals are produced (SiO 2 —Li 2 O). In addition to the composition, we have implemented a process for our glass ceramic that produces a homogeneous product and that can be used only with our specific formulation. This process cannot be used with the other prior art glass ceramics due to the lower operating temperatures.
[0035] It is emphasized that in the present glass ceramic the silicon dioxide and lithium oxide molar ratio content (SiO 2 /Li 2 O) is less than 2, specifically the oxide molar ratio is preferably about 1.7. This is specifically equivalent to 63% molar of silicon dioxide and 37% molar of lithium oxide, and specifically equivalent in the overall formulation of about 56% weight percent of all of the glass ceramic as silicon dioxide and 16.0% weight percent as lithium oxide and the remaining 28% composed of the oxide additives and modifiers. In all of the glass ceramic, only lithium silicate (Li 2 O.SiO 2 ) crystals are produced as the final crystal phase product. During the heating process of the glass, the first crystals formed are stable lithium silicate and not metastable lithium metasilicate and such crystals remain stable through the end of the growing process. This means that there is no need for a third thermal process for producing the final crystal of lithium silicate making this an additional beneficial characteristic unique to the present invention. This new ceramic has a softening temperature of about 700 to 800° C. and a linear thermal coefficient of expansion of about 12 to 12.5×10 −6 /° C. as a final product and a composition yielding completely different chemical and physical properties compared to the prior art. This is easily demonstrated in commonly assigned U.S. patent application Ser. No. 12/1592,825, paragraph [0012], FIG. 1 showing a XRD pattern diffraction where only lithium silicate crystals are present in the final product and in paragraph [0013] thereof where the glass ceramic is shown to have a percentage linear change of 0.55% measured at 500° C. and an equivalent coefficient of thermal expansion of 11.5×10 −61 /° C.
[0036] The following is a list of non-patent references noted herein:
[0037] 1. BOROM, P. et al, Strength And Microstructure In Lithium Disilicate Glass-Ceramics. The authors prepare lithium disilicate glass ceramics and measured the differences between the thermal expansion of the lithium disilicate with a value of 13×10 −6 /° C. and lithium silicate with a value of 11.4×10 −6 /° C. After the heat treatment above 800° C. the only phase present is lithium disilicate for a glass ceramic composition of 71.8% of silicon dioxide and 12.6% of lithium oxide.
[0038] 2. EPPLER, A., Glass Formation And Recrystallization In The Lithium Metasilicate Region Of The System Li 2 O—Al 2 O 3 —SiO 2 J. Am. Ceram. Soc., 46, {2}, 97-101, (1963).
[0039] 3. HUMMEL, F. A., Thermal Expansion Properties Of Some Lithia Minerals, J. Am. Ceram. Soc., 34{8} 235-39. (1951).
[0040] 4. LANDOLT-BÖRNSTEIN (LB), Zahlenwerte und Funktionen aus Physik, Chemie, Astronomie, Geophysik und Technik.
[0041] 5. S. CLAUS et al, Phase Equilibria In The Li 4 SiO 4 —Li 2 SiO 3 Region Of The Pseudobinary Li 2 O—SiO 2 , Journal of Nuclear Materials, Volume 230, Issue 1, May 1996, Pages 8-11.
[0042] 6. SHERMER, HERMAN, Thermal Expansion Of Binary Alkali Silicate Glasses, Journal of Research of the National Bureau of Standards. Vol. 57, No. 2, August 1956. The author prepares lithium silicate glasses with silicon oxide and lithium oxide molar ratio below 2.0 being lithium silicate with thermal expansion between 12 and 14.77×10 −6 /° C. There is no lithium disilicate using this chemical molar composition.
SUMMARY OF THE INVENTION
[0043] The present invention relates to preparation of an improved lithium silicate glass ceramic for the manufacture of blocks for dental appliance fabrication using a CAD/CAM process and hot pressing. The lithium silicate material has a chemical composition that is different from those reported in the prior art, especially because of the use of germanium dioxide in the formulas and a low silicon dioxide content. The softening points are close to the crystallization final temperature of 800° C. indicating that the samples will support the temperature process without shape deformation.
[0044] The initial components are chemical precursors, specifically aluminum hydroxide for aluminum oxide, boric acid for boron oxide, lithium carbonate for lithium oxide, ammonium hydrogen phosphate or calcium phosphate for phosphorus pentoxide, zirconium silicate or yttrium stabilized zirconia for zirconium oxide, calcium carbonate for calcium oxide, lithium fluoride for lithium oxide and fluoride, and potassium carbonate for potassium oxide. The remaining elements are single oxide precursors of silicon, cerium, titanium, tin, erbium, vanadium, germanium, samarium, niobium, yttrium, europium, tantalum, magnesium, praseodymium, and vanadium oxides.
[0045] The components are carefully weighed and then mechanically blended using a V-cone blender for about 5 to 10 minutes. Then in order to achieve uniform particle size of the components, the mixture undergoes a ball mill process for two hours. The powder obtained is put into large alumina crucibles and undergoes calcination to 800° C. for about 4 hours. In this stage the carbonate precursors, lithium carbonate, calcium carbonate, potassium carbonate, decompose releasing carbonic gas and producing the corresponding pure oxides, lithium oxide, calcium oxide and potassium oxide, respectively. In the same process the other chemical precursors, ammonium phosphate, aluminum hydroxide and boric acid also release nitrogen gases and water, producing the corresponding pure oxides, phosphorous pentoxide, aluminum oxide and boron oxide, respectively. At this stage of calcination the original powder mix loses approximately 25% of its original weight due to the evaporation losses. Also, the first reactions between the pure oxides take place in this stage, but there is never any melting of the components and no reaction takes place with the alumina crucible. After cooling down, the blend of components undergoes ball milling again, producing a homogeneous, gas free, fine powder with a particle size below 30 microns. The calcined powder can be safely stored in plastic containers for extended periods of time without any gas release and can be used any time for the next step of the process.
[0046] In the final stage of the process, the calcined powder is melted in a platinum crucible at a temperature of 1200° C. with a holding time of about 2 hours before casting. The melt with the appropriate viscosity is cast continuously over graphite molds. Surprisingly, the glass cast is bubble free due to the prior elimination of the gases during the calcination step. This constitutes a significant advantage over the processes described in the prior art. Due to the calcination process step, there is no need for a second re-melting process for improving homogeneity. The glass cast is then subjected to an annealing step followed by an intermediate crystallization step or a full crystallization step depending on what is desired as a final product.
[0047] Due to the specific molar ratio of silicon dioxide and lithium oxide (1.711) used in the preferred embodiments of the present invention, the only preferred crystal structure formed is lithium silicate (SiO 2 .Li 2 O) in the intermediate or full crystallized product. Surprisingly we found that in this invention, the crystal growth process can be momentarily stopped at any temperature interval between the ranges of 350° to 800° C. and then the crystal can continue growing by heating it again to reach the optimal size at 800° C. Above 800° C. the sample starts melting and the reverse process of dissolving the crystals in the glass matrix takes place.
[0048] Thus in the present invention, the intermediate crystallization process step is easily controlled by stopping the heating process at 600° C. and cooling down to room temperature. It can then be heated again to 800° C. for achieving the full crystallized product. Thus if we take the intermediate block material of lithium silicate, after the thermal heat process from room temperature to 600° C., it can be milled to a dental restoration using conventional CAD/CAM devices and then it can be heated up again to 800° C. continuing towards maximum crystal growth and achieving the optimal physical properties. Surprisingly, the same formulation, after a thermal process from room temperature to 800° C., can be easily hot pressed in the range of 800-840° C. using conventional all ceramic dental investments and commercial press furnaces (i.e., Whip Mix Pro-Press 100). For the hot press process, the dental restoration is milled in a wax block, followed by investing the wax pattern using commercial all ceramic investments. After firing the investment, the wax is burned out, allowing the cavity of the restoration to become available to fill with the ceramic. After hot pressing, the restoration achieves the optimal physical properties.
[0049] The same formulation produces the same lithium silicate crystalline phase through all the thermal process steps and the dental restoration can be optimally achieved by using either CAD/CAM or hot press techniques. Being able to achieve this with the same formulation is a unique and advantageous characteristic compared to the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0050] The aforementioned objects and advantages of the present invention, as well as additional objects and advantages thereof, will be more fully understood herein after as a result of a detailed description of a preferred embodiment when taken in conjunction with the following drawings in which:
[0051] FIG. 1 shows the thermal pattern profile employed for this invention from the melting glass temperature to the formation in a one or two step process of the stable lithium silicate glass ceramic. For the one step process, the cast glass ceramic is heated from point 2 to point 4. For the two step process, the cast glass ceramic is heated from point 2 to point 3 and then after milling the dental restoration is heated again from point 3 to point 4. In the first stage of the process (2 to 3), the size of the crystals of lithium silicate are controlled to a specific size and its growing process stopped by decreasing the temperature. Then in the second step the same crystals formed in step 1 continue to growth during heating again in order to achieve the appropriate crystal size.
[0052] FIG. 2 is an XRD diffraction pattern of a sample of the invention after the intermediate crystallization step (from room temperature to 600° C.) showing the presence of lithium silicate as a main constituent phase in the glass ceramic composition;
[0053] FIG. 3 is an XRD diffraction pattern of a sample of the invention after the full crystallization step (from room temperature to 800° C.) showing the presence of lithium silicate as a main constituent phase in the glass ceramic composition. Because the molar ratio of SiO 2 /Li 2 O is between 1.7 to 1.9, the crystallized phase of the final material shows the presence of mainly lithium silicate and no lithium disilicate;
[0054] FIG. 4 is an XRD diffraction pattern of a sample of this invention after hot pressing in the interval of 800° C. to 840° C. showing the presence of lithium silicate as a main constituent phase in the glass ceramic composition. Because the molar ratio of SiO 2 /Li 2 O is between 1.7 to 1.9, the crystallized phase of the final material shows the presence of mainly lithium silicate and no lithium disilicate; and
[0055] FIG. 5 is a graphical illustration of a dilatometric measurement of a sample of the invention resulting from full crystallization. The softening temperature of the intermediate step is lower than the temperature after full crystallization This is due to the crystal growth after heating the glass in the intermediate stage from room temperature to 800° C.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0056] The prior art materials are based on the formation of lithium disilicate materials. A principal object of the present invention is to prepare a controlled lithium silicate glass ceramic using in the formulation a specific silicon dioxide and lithium oxide molar ratio with excellent physical properties for manufacturing dental restorations. The glass material subjected to a heat treatment produces an optimal lithium silicate crystal forming a glass ceramic product with outstanding mechanical properties, excellent optical properties, a very good chemical solubility, little contraction and high flexural strength values.
[0057] The lithium silicate of the present invention preferably comprises the following components and compositions:
[0000]
weight % composition
Component
minimum
maximum
SiO 2
53.0
57.0
A1 2 O 3
3.0
5.0
K 2 O
3.0
5.0
CaO
0.0
1.0
B 2 O 3
0.0
2.0
CeO 2
0.0
1.0
MgO
0.0
1.0
Fluorine
0.0
1.0
Li 2 O
14.0
17.0
ZrO 2
4.0
6.0
TiO 2
0.0
3.0
P 2 O 5
2.0
3.0
SnO
0.0
1.0
Er 2 O 3
0.0
2.0
V 2 O 5
0.0
1.0
GeO 2
0.5
8.0
Ta 2 O 5
0.0
3.0
Sm 2 O 3
1.0
6.0
Pr 2 O 3
0.0
1.0
Eu 2 O 3
0.0
2.0
Y 2 O 3
0.0
5.0
Nb 2 O 5
0.0
1.0
[0058] The invention is explained in more detail below with the following examples:
[0059] The sample preparation and its elemental oxide composition are listed in Table 1.
[0000]
TABLE 1
Components % weight
Example
Example
Example
Example
Example
1
2
3
4
5
SiO 2
55.03
56.19
56.21
56.21
53.88
Al 2 O 3
4.09
4.18
4.18
4.18
3.11
K 2 O
4.42
4.52
4.52
4.52
3.44
CaO
0.94
0.96
0.96
0.96
0.00
B 2 O 3
1.58
1.61
1.61
1.61
0.00
CeO 2
0.21
0.65
0.34
0.41
0.63
MgO
0.22
0.23
0.23
0.23
0.00
Fluorine
0.49
0.50
0.50
0.50
0.00
Li 2 O
15.81
16.14
16.15
16.15
14.81
ZrO 2
4.70
4.79
4.80
4.80
4.88
TiO 2
2.40
0.80
0.80
0.80
0.63
P 2 O 5
2.52
2.58
2.58
2.58
2.94
SnO
0.22
0.07
0.13
0.12
0.00
Er 2 O 3
0.37
0.76
0.36
0.21
1.26
V 2 O 5
0.39
0.22
0.26
0.11
0.03
GeO 2
0.90
0.92
0.92
0.92
7.75
Ta 2 O 5
0.07
0.15
0.22
0.01
0.00
Sm 2 O 3
2.03
4.09
4.07
4.09
5.71
Pr 2 O 3
0.03
0.33
0.04
0.00
0.88
Eu 2 O 3
0.00
0.00
0.00
1.25
0.05
Y 2 O 3
3.13
0.11
0.61
0.36
0.00
Nb 2 O 5
0.46
0.22
0.53
0.00
0.00
TOTAL
100.00
100.00
100.00
100.00
100.00
Example 6
Example 7
Example 8
Example 9
Example 10
SiO 2
54.08
54.49
56.17
53.49
56.19
A1 2 O 3
3.12
3.86
4.18
3.98
4.18
K 2 O
3.45
4.20
4.52
4.30
4.52
CaO
0.00
0.00
0.96
0.92
0.96
B 2 O 3
0.00
0.00
1.61
1.53
1.61
CeO 2
0.95
0.64
0.00
0.20
0.62
MgO
0.00
0.00
0.23
0.22
0.23
Fluorine
0.00
0.00
0.50
0.48
0.50
Li 2 O
14.85
15.25
16.15
15.37
16.14
ZrO 2
4.89
4.88
4.80
4.56
4.79
TiO 2
0.63
0.64
0.80
0.78
0.80
P 2 O 5
2.95
2.97
2.58
2.45
2.58
SnO
0.00
0.00
0.00
0.00
0.07
Er 2 O 3
1.52
1.28
0.05
0.16
0.61
V 2 O 5
0.06
0.04
0.00
0.48
0.15
GeO 2
7.77
7.70
0.92
0.87
0.92
Ta 2 O 5
0.00
0.00
2.33
0.00
0.18
Sm 2 O 3
4.82
3.34
1.83
4.90
4.05
Pr 2 O 3
0.90
0.72
0.00
0.23
0.24
Eu 2 O 3
0.00
0.00
0.05
0.00
0.00
Y 2 O 3
0.00
0.00
2.33
4.90
0.24
Nb 2 O 5
0.00
0.00
0.00
0.18
0.45
TOTAL
100.00
100.00
100.00
100.00
100.00
[0060] A particularly preferred lithium silicate material as described in the examples 1 to 10 comprises 53 to 59 wt. % of SO 2 , 14 to 19% wt. of Li 2 O and 1 to 9% of GeO 2 , where after nucleation only lithium silicate is formed and then after complete crystal growth only lithium silicate crystals are formed.
[0061] The lithium silicate material of this invention is preferably produced by a process which comprises the following steps:
(a) A mix of the precursors of the final components of the table 1, are blended together for 10 to 30 min until a mechanical mix is obtained. (b) The mix is ball milled dry or wet using zirconia media for about 1 to 2 hours to homogenize the components and achieve almost the same particle size in all the components. (c) The sample is calcined at 800° C. for about to 4 hours in order to decompose the precursors to their primary oxides and eliminate any possibility of formation of gas after the process. (d) Ball-mill the sample of step (c) in order to produce a powder with an average particle size below 30 microns. (e) The powder of step (d) is melted in a platinum crucible at a temperature between 1100 to 1200° C. for 1 to 2 hours. It is then poured into cylindrical or rectangular graphite molds and cooled down to room temperature. (f) The glass ceramic of step (e) is then subjected to an intermediate crystal growth process at a temperature of from room temperature to 600° C. for 10 to 60 min. The growth of the lithium silicate crystals is temporarily stopped for the desired intermediate size by cooling the glass ceramic to room temperature. (g) The glass ceramic of step (f) is subjected to a single step heating cycle from room temperature to 800° C. to achieve full crystallization. (h) For use in a CAD-CAM milling device, the dental restoration is made using a block after intermediate process step (f). After milling, the restoration is heated again from 350° C. to 800° C. or to full crystallization step (g) where the optimal lithium silicate crystal growth in the glass ceramic is achieved in a single step program. (i) For an alternative hot pressing technique, the sample after [step (g)] is pressed into a dental restoration at a temperature of 800-840° C., where the optimal lithium silicate crystal growth in the glass ceramic is achieved.
Coefficient of Thermal Expansion and Softening Point
[0071] The percentage linear change vs. temperature was measured using an Orton dilatometer. The coefficient of thermal expansion at 500° C. and the softening point were calculated for all the samples. For this purpose a rectangular rod of approximately 2 inches long was cast and then subjected to the intermediate crystallization cycle at 600° C. for 40 min. After this process the rod is cut into two parts. One part is used for measuring transition temperature, softening point temperature, and coefficient of thermal expansion of that process step. The second part is fully crystallized at 800° C. for about 10 minutes and is used for measuring the same properties. It is expected that after the crystallization step, the softening temperature point increases for the samples due to the formation of larger lithium silicate crystals. Test results are displayed in Table 2.
Flexural Strength
[0072] Biaxial flexural strength tests (MPa) were performed following ISO-6872 procedures. Ten round samples were cut, ground gradually and polished to a mirror finish in the intermediate stage of step (f). The samples were then fully crystallized in a single stage program from 350° C. to 800° C. for 10 minutes. Then the biaxial flexural strength was measured. For the hot pressing technique the glass ceramic of sample of step (g) is hot pressed into round discs in the interval of 800 to 840° C. Then the discs are ground gradually and polished to a mirror finish, heated as a simulated glaze cycle, and tested. Test results expressed in MPa are displayed in Table 2.
Chemical Solubility
[0073] A chemical solubility test was performed according to ISO-6872. Ten discs samples subjected to step (g) are placed in a glass flask with an aqueous solution of 4% (V/V) of acetic acid analytical grade (Alfa Aesar). The flask is heated to a temperature of 80 +/−3° C. for 16 hours. The change in weight before and after the test is determined and then the chemical solubility expressed as μg/cm 2 is calculated and shown in Table 2.
[0000]
TABLE 2
Physical Properties of the Lithium silicate glass ceramic
Example
Example
Example
Example
Example
#2
#3
#4
#5
#8
Softening temperature, ° C.,
689
618
690
766
711
Intermediate stage at 600° C.
Softening temperature, ° C.
727
744
717
789
724
crystallized sample at 800° C.
Coefficient of expansion, X10 −6 /° C.
11.81
12.58
12.27
11.30
11.61
Crystallized sample at 800° C.
Flexural strength, MPa,
350+/−28
402+/−56
359+/−40
365+/−60
370+/−50
Crystallized at 800° C.
Flexural strength, MPA
393+/−48
423+/−61
533+/−39
345+/−20
397+/−57
Hot pressed sample
Chemical Solubility, μg/cm 2
72
58
65
39
58
Crystallized sample at 800° C.
[0000]
TABLE 3
Quantitative analysis of the crystalline phases of Lithium Silicate
intermediate stage and fully crystallized stage with average crystal size
Quantitative Phase Analysis (wt. %)
Chemical
Lithium Silicate partially
Lithium Silicate fully
formula
crystallized at 600° C.
crystallized at 800° C.
Li 2 SiO 3
43.1%
(183Å)
54.1%
(767Å)
Li 3 PO 4
5.3%
(738Å)
Amorphous
56.9%
40.6%
[0074] The table 3 shows the quantitative analysis of the crystalline phases present in the two samples. The partially crystallized sample contains mainly Lithium silicate whereas the fully crystallized sample contains 91% as lithium silicate and 9% as lithium phosphate of the total crystalline phases present. Only two heating steps are necessary ( FIG. 1 ). For the one step process the casted glass ceramic is heated from 2 to 4 of the graph of FIG. 1 . For the two step process the casted glass ceramic is heated from 2 to 3 of the graph of FIG. 1 and then after milling the dental restoration heated again from 3 to 4. In the first stage of the process (2 to 3), the size of the crystals of lithium silicate are controlled to an average value of 183 Angstroms. At this crystal size stage the glass material can be easily milled to a dental restoration using conventional CAD/CAM devices. Then the growing process is stopped by decreasing the temperature and subsequence increase in the glass viscosity. Then in the second step the same crystals formed in step 1 continue to growth during heating again to a size averaging 770 Angstroms. Those values are calculated from the XRD patterns. The lithium silicate glass ceramic produced by this process achieves an extraordinary translucency and shade that resemble natural teeth. The total weight percentage of the crystalline phase achieved is about 60%. During these two heating steps, the mainly crystal phase present is lithium silicate and there is no lithium disilcate.
[0075] The preferred range composition (in % of this glass ceramic material is the following:
[0000]
TABLE 4
Preferred Range of Composition Components
weight % composition
Component
minimum
maximum
SiO 2
53.5
56.2
A1 2 O 3
3.1
4.2
K 2 O
3.4
4.5
CaO
0.0
1.0
B 2 O 3
0.0
1.6
CeO 2
0.0
1.0
MgO
0.0
0.2
Fluorine
0.0
0.5
Li 2 O
14.8
16.1
ZrO 2
4.6
6.0
TiO 2
0.6
2.4
P 2 O 5
2.5
3.0
SnO
0.0
0.2
Er 2 O 3
0.1
1.5
V 2 O 5
0.0
0.5
GeO 2
0.9
7.8
Ta 2 O 5
0.0
2.3
Sm 2 O 3
1.8
5.7
Pr 2 O 3
0.0
0.9
Eu 2 O 3
0.0
1.3
Y 2 O 3
0.0
4.9
Nb 2 O 5
0.0
0.5
[0076] One preferred example of this material has the following specific composition:
[0000]
TABLE 5
Preferred Composition
Component
Weight %
SiO 2
55.74
A1 2 O 3
4.15
K 2 O
4.48
CaO
0.95
B 2 O 3
1.60
MgO
0.23
Fluorine
0.50
Li 2 O
16.01
ZrO 2
4.76
TiO 2
0.80
P 2 O 5
2.56
GeO 2
0.91
Coloring oxides
7.32
[0077] Having thus disclosed a number of embodiments of the formulation of the present invention, including a preferred range of components, a preferred formula thereof and a preferred fabrication process, those having skill in the relevant arts will now perceive various modifications and additions. Therefore, the scope hereof is to be limited only by the appended claims and their equivalents. | A method of fabricating a one crystalline phase lithium silicate glass ceramic and the manufacture of machinable blocks for dental appliances using a CAD/CAM device. The resulting glass ceramic contains a thermodynamically stable lithium silicate crystal through each of the steps of the process due to its specific material formulation. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to a pressure sensitive transferring adhesive tape which is prepared by forming an adhesive agent layer on a substrate tape.
BACKGROUND OF THE INVENTION
[0002] As a kind of double-sided adhesive tape, a non supported double-sided adhesive tape that does not have a supporter (core material) and transfers adhesive agent layer alone to an adherent is well-known and is widely used in various fields as a pressure sensitive transferring adhesive tape. The conventional structural feature of said pressure sensitive transferring adhesive tape is illustrated as follows. That is, an adhesive agent layer is formed on one surface of a releasable liner or a releasable substrate and is wound like a roll. Recently a transferring device characterizing by attaching these small wound type tape roll to a transferring tool is developed and is on the market for the office supplies uses under the name of “tape adhesive”.
[0003] The transferring device is consisted of;
[0004] a feeding reel to which a pressure sensitive transferring adhesive tape is wound;
[0005] a transferring head that transfers the adhesive agent layer of the pressure sensitive transferring adhesive tape provided from the feeding reel to an adherent by releasing from the substrate;
[0006] and a winding up reel to wind up the used substrate after transferring.
[0007] These are arranged in a case that can be handled by one hand.
[0008] The transferring device is illustrated by FIG. 1. In FIG. 1, a feeding reel 2 which winds and stores the pressure sensitive transferring adhesive tape 5 in a roll state, and a winding up reel 3 which winds up and stores the used substrate after transferring are arranged in a case 1 . Said case 1 is a main body of the pressure sensitive transferring device that can be handled by one hand, and is to expose a part of the pressure sensitive transferring adhesive tape from the end point of the case so as the transferring head 4 , which transfers the adhesive agent layer to the adherent by releasing it from the substrate, to contact to the adherent.
[0009] When said pressure sensitive transferring adhesive tape is used for the adhering means of paper, it displays following strong points compared with the conventional liquid type adhesives or solid type adhesives. Namely, adhesive agent can be easily transferred to the surface of the adherent without making the hands of operator sticky, the drying up time to complete the adhering process is not needed, and the paper, which is the adherent, is not wrinkled. Further, after the necessary length of adhesive tape is transferred to the surface of the adherent, the adhesive agent layer can be cut easily by lifting the transferring device vertically from the surface of the adherent or by moving it to the horizontal direction. Therefore, compared with the conventional double-sided adhesive tape with supporter, it is not necessary to cut the tape previously to the necessary length, and since the releasable substrate from which the adhesive agent layer is released is wound up to the winding up reel, there is no waste at the actual use. That is, it can be said as a very convenient adhesive goods.
[0010] However, since the adhesive agent of adhesive agent layer is coated continuously on the surface of releasable substrate, the adhesive agent causes stringiness and stretching problem at the cutting action and cannot be cut smoothly, which is recognized as the problem so called poor adhesive severability.
[0011] To avoid the problem, the methods to make the adhesive agent layer form fine dotted shape or to arrange the adhesive agent layer so as to form block shape keeping a distance between blocks are proposed, however, these proposed methods have a problem that the adhering strength becomes weaker in comparison with that of the continuous coating method.
[0012] The inventors of this invention have conduced a intensive study to dissolve the above mentioned problem and accomplished the present invention, and the object of the present invention is to provide a pressure sensitive transferring adhesive tape which has the excellent adhesive severability maintaining the sufficient adhering strength.
SUMMARY OF THE INVENTION
[0013] The above mentioned object can be accomplished by a pressure sensitive transferring adhesive tape, comprising a substrate on which surface an adhesive agent layer is provided, said adhesive agent layer is characterized to be coated over the surface of the substrate so as to form discontinuous island shape pattern, and the surface area of said one island is from 1 to 100 mm 2 , further the distance between adjacent islands is from 0.1 to 4 mm.
[0014] Further, said object can also be accomplished by a pressure sensitive transferring adhesive tape, comprising a substrate on which surface an adhesive agent layer is provided, the surface of said adhesive agent layer is characterized to have concave and convex shape, and the thickness of concave part is thinner than 80 % of the thickness of convex part, further the gel fraction of said adhesive agent layer is bigger than 15% by weight.
[0015] Furthermore, it is desirable that the viscosity at 25° C. of adhesive agent composition at the coating process is from 0.1 to 50 Pa·S, and the content of involatile component in said adhesive agent composition is from 10 to 80%.
BRIEF ILLUSTRATION OF THE DRAWINGS
[0016] [0016]FIG. 1 ( a ) is the front cross sectional view of one example of the pressure sensitive transferring device that uses the pressure sensitive transferring adhesive tape of the present invention, and FIG. 1 ( b ) is the side view thereof. This transferring device is provided with a feeding reel 2 which winds and stores the above mentioned pressure sensitive transferring adhesive tape 5 by roll shape, and a winding up reel 3 which winds up and stores the used substrate after transferring are arranged in a case 1 , which is a main body of the pressure sensitive transferring device, and can be handled by one hand. Said case is to expose a part of the pressure sensitive transferring adhesive tape from the end point of the case so as the transferring head 4 , which transfers the adhesive agent layer to the adherent by releasing it from the substrate, to contact to the adherent.
[0017] [0017]FIG. 2 is a drawing to illustrate the testing method of abrasive severability.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0018] The present invention will be illustrated more in detail.
[0019] First of all, the case that the adhesive agent of adhesive agent layer of this invention is coated forming discontinuous islands shape pattern is illustrated. The surface area of an individual island of said adhesive layer coated forming the island shape pattern is from 1 to 100 mm 2 , desirably from 3 to 36 mm 2 , and the distance between adjacent islands is from 0.1 to 4 mm, desirably from 0.3 to 2.5 mm. If the surface area of an individual island is larger than 100 mm 2 , the degree of freedom to select the cutting position of the adhesive agent layer becomes limited, on the contrary, if the surface area of individual island is smaller than 1 mm 2 , the contact of the adhesive agent to the adherent becomes not by “area” but by “point” and the sufficient adhesive power can not be obtained. Further, when the distance between adjacent islands is wider than 4 mm, the effective adhesive agent area becomes small and the sufficient adhering strength cannot be obtained. And, when the distance is narrower than 0.1 mm, the adjacent adhesive agent layer contacts with each other, because of the fluidity that the adhesive agent has. Therefore, it becomes difficult to coat the adhesive agent on a substrate by the intended pattern, and the sufficient adhesive severability cannot be obtained.
[0020] The island shape pattern of this invention means the pattern that the adhesive agent exists at random scatterly, or exists regularly forming a pattern. The shape of the individual island can be voluntarily selected, and it is desirable that the individual islands are completely divided. The thickness of the adhesive agent layer is usually from 1 to 50 μm, and desirably is from 2 to 30 μm. By altering the kind of adhesive agent or coating thickness, various adhesive agent layers having different properties that meets to the uses, such as permanent adhering type or re-releasable type can be obtained.
[0021] The adhesive agent layer of the pressure sensitive transferring adhesive tape of the present invention is a layer prepared by coating the adhesive agent on a surface of the releasable substrate by island shape pattern.
[0022] As the adhesive agent, any kinds of conventional adhesive can be used. For example, acrylic type, rubber type, silicone type or rosin type can be mentioned, and any kind of additives such as filler, preserving agent or pigment can be used when need is arisen.
[0023] As the substrate, any kind of materials which have releasing effect to the adhesive can be voluntarily used. For example, plastic films such as polyethylene, polyethyleneterephthalate, polypropylene or polyvinylchloride, paper such as glassine paper or metallic foil can be mentioned. To one or both surface of the substrate, a releasable layer composed of silicon resin or fluorocarbon resin can be formed to provide the releasing effect when need is arisen. The adequate thickness of the substrate is from 10 to 60 μm. And, as a method to coat the adhesive agent forming a discontinuous island shape pattern, any kind of methods such as a silkscreen method, a gravure method or an inkjet method can be used.
[0024] Secondly, the case that the surface of the adhesive agent layer has a concave and convex shape is illustrated. Regarding to the concave and convex shape, the thickness of concave part is thinner than 80% of the thickness of convex part. When the thickness of concave part is thicker than 80% of the thickness of convex part, the excellent adhesive tearing ability cannot be obtained. Desirably, the thickness of concave part is thinner than 60% of the thickness of convex part. The substantial thickness of convex part is 2 to 200 μm, and desirably is 5 to 60 μm. In the adhesive agent layer, the thick portion is the thickness of the convex part and the thin portion is the thickness of the concave part.
[0025] The thickness of the adhesive agent layer is measured by following method. That is, a specimen is frozen using liquid nitrogen and sliced by a sharp edged tool, then the cross section is observed by an optical microscope or by an electronic microscope, and the thickness of concave and convex part of the adhesive agent layer are measured.
[0026] As the materials of a substrate A on which surface the adhesive agent layer having concave and convex shape can be formed, any kind of materials which have releasing effect to the adhesive can be voluntarily used. For example, plastic films such as polyethylene (PE), polyethyleneterephthalate (PET), polypropylene (PP) or polyvinylchloride (PVC), paper such as glassine paper or metallic foil can be mentioned. To one or both surface of the substrate, a releasable layer composed of silicon resin or fluorocarbon resin is formed to provide releasing effect when need is arisen. The adequate thickness of the substrate A is from 10 to 60 μm.
[0027] Further, in the present invention, it is necessary that the gel fraction of said adhesive agent layer is bigger than 15%, desirably bigger than 30% by weight. When the gel fraction is low, the coagulating force of the adhesive agent layer becomes weak, and in the case when embossed separator is removed and wound up by a (releasable) substrate, the adhesive agent layer is flown by the winding pressure. It causes a problem that the concave and convex shape becomes unclear. Therefore, in the present invention, the gel fraction of the adhesive agent layer is settled to bigger than 15%, desirably bigger than 30%. The actual gel fraction of acrylic type adhesive layer can not reach to 100% even if the degree of cross-linking is elevated to the highest level, and substantially the maximum value is 98% around.
[0028] The gel fraction is measured by the following method.
[0029] That is, the pressure sensitive adhesive tape is cut to the prescribed size and the substrate is removed from, thus the specimen of adhesive agent layer is prepared. As the first step, the weight of specimen is weighted. Then the specimen is dissolved into ethyl acetate for two days at the condition of 23° C. and 65% RH. After that, the insoluble part is filtrated by a metallic sieve of 200 mesh and weighted. Calculate the ratio (%) of the insoluble part to the initial weight of the specimen, and the calculated result is the gel fraction.
[0030] The preparation method of the pressure sensitive adhesive tape whose shape of the adhesive agent layer is concave and convex shape is illustrated. As the method to form concave and convex shape on the adhesive agent layer, any kind of methods such as a screen method, a gravure method or an embossed separator method can be used, however, among these methods, the embossed separator method is desirably used.
[0031] The embossed separator method is a method to use a releasing substrate as a “mold” and said releasing substrate is provided with a concave and convex shape (this releasing substrate is called as an embossed separator or simply shortened as a substrate B) by means of an emboss treatment, a sand brushing or a chemical treatment. Adhesive agent composition is applied to the surface of the embossed separator, dried up and the adhesive agent layer is formed on the surface of the embossed separator. Then, the substrate A is stuck on it so as said adhesive agent layer to transfer on the surface of substrate A. After that, said embossed separator is released and thus the pressure sensitive adhesive tape is obtained.
[0032] As the timing to release the embossed separator, any time when the formed concave and convex shape is not get out of shape can be selected. Even if, in a case which needs aging term, the embossed separator can be released before the aging process. Of cause, the embossed separator can be stuck during whole forming term. Or, it is possible to prepare a commercialized goods without releasing the embossed separator, and in this case the embossed separator should be released at the actual use. Further, the embossed separator itself can be used as the substrate A of the pressure sensitive adhesive tape, without sticking the substrate A on the adhesive agent layer.
[0033] The embossed separator method is different from a screen method or a gravure method, and the adhesive agent composition can easily form the concave and convex shape, because after coated the adhesive agent composition stays on the embossed separator, which is the mold to form the concave and convex shape, until it looses fluidity by a drying process. Further, in cases of a screen method or a gravure method, since a roll or a screen (pattern) must be prepared according to the intended concave and convex shape, the changing of the pattern is not so easy, while in the case of the embossed separator method, there is a strong point that the adhesive agent layer of concave and convex shape can be obtained by using a conventional coating machine used for a flat coating.
[0034] As an embossed separator that can be used for the embossed separator method, any kind of materials which has releasability or a substrate such as film whose surface is treated to have the releability can be mentioned. As the concrete example of the materials, plastic films such as polyethylene (PE), polyethyleneterephthalate (PET), polypropylene (PP) or polyvinylchloride (PVC), paper such as glassine paper or metallic foil can be mentioned, however, not intended to be limited to them. The treatment to provide a releasing effect is carried out to one or both surface of the embossed separator (substrate B) by applying releasing agent such as silicon resin or fluorocarbon resin when need is arisen. The releasing treatment can be carried out before or after the process to provide the concave and convex shape to the embossed separator (substrate B). The preferable thickness of the embossed separator is from 20 μm to 300 μm around.
[0035] As the pattern of concave and convex shape to be provided to an embossed separator, voluntary shape including a circular shape, a multiple angle shape larger than triangle, a corrugated shape or other random shape can be used, and among these shapes, a circular shape, a regular triangle shape, a perfect square shape, a diamond shape, a regular pentagonal shape, a regular hexagonal and a regular octagonal shape are desirably used. And the numbers of islands per one cm 2 is 0.25 to 1000, desirably 2 to 400.
[0036] As the means to coat the adhesive agent composition on an embossed separator, any kind of coating machine used for a conventional coating process, such as a roll coater, a die coater, a gravure coater, a bar coater or a knife coater can be used.
[0037] As the adhesive agent which compose the adhesive agent layer of the present invention, any kind of conventional adhesive agent used for this kind of adhesive tape can be used. For example, an adhesive agent such as acrylic type, rubber type, silicone type, rosin type, urethane type and polyvinylether type can be mentioned, and these types can be used by solvent state, emulsion state or by non solvent state. It is desirable to blend a hardener to the adhesive agent, further, other additives such as a filler, a preserving agent or a pigment can be added when need is arisen.
[0038] When the viscosity of the adhesive agent composition used in this invention is low, the shedding phenomenon of the adhesive agent composition is caused on the surface of embossed separator and the good-coated surface cannot be obtained. While, the viscosity is too high, the defects of uneven coating or stripes are caused and deteriorate the smoothness of the coated surface. And this can be the ground to deteriorate the formation of concave and convex shape and to affect the adhesive property. In the present invention, the adhesive agent composition whose viscosity at 25° C. is from 0.1 to 50 Pa·S, desirably from 2.0 to 20 Pa·S is used. Further, the content of involatile component of said adhesive agent composition is from 10 to 80%, and when is smaller than 10% the formation of concave and convex shape is not sufficient. While, when the content of involatile component is over than 80% the formation of concave and convex shape becomes better, however, it is necessary to make the clearance of a coater head part narrower at the coating process, and causes a problem of preparing process that the embossed separator becomes easy to be broken.
[0039] The viscosity of the adhesive agent composition used in the present invention is measured based on the method prescribed in JIS K6 833 6.3 at 25 ±2° C., and as the viscometer, BM type or BL type viscometer of Tokyo Keiki Co., Ltd, is used.
[0040] Further, the content of involatile component of said adhesive agent composition used in the present invention is from 10 to 80%. The content of involatile component is measured by the measuring method based on the method prescribed in JIS K5404 4. That is, 1 to 1.5 gr of the adhesive agent composition, which is the specimen, is contained into a glass container of 60 mm diameter and 40 mm height, and heated in a dryer of 105-110° C. temperature for 3 hours without using a cover so as the volatile component to volatilize. Calculate the ratio (%) of the weight of residue to the initial weight of the specimen, and obtained ratio is the content of involatile component.
EXAMPLES
[0041] The present invention will be illustrated more readily according to the Examples, however, not intended to be limited to the Examples.
Example 1
[0042] Acrylic type adhesive agent is coated by using screen printing method on a surface of a tape substrate made of PET whose both surface is treated a releasable treatment. The adhesive agent layer is coated to form the islands shape pattern, wherein the area of one island is 20 mm 2 and the distance between adjacent islands is 1 mm. Thus the pressure sensitive transferring adhesive tape is obtained.
Comparative Example 1
[0043] The pressure sensitive transferring adhesive tape is obtained by the same process to Example 1, except making the area of one island 105 mm 2 .
Comparative Example 2
[0044] The pressure sensitive transferring adhesive tape is obtained by the same process to Example 1, except making the area of one island 0.8 mm 2 .
Comparative Example 3
[0045] The pressure sensitive transferring adhesive tape is obtained by the same process to Example 1, except making the distance between adjacent islands 5 mm.
Comparative Example 4
[0046] The pressure sensitive transferring adhesive tape is obtained by the same process to Example 1, except making the distance between adjacent islands 0.05 mm. Since the distance between adjacent islands is too narrow the islands are contacted each other and intended island shape pattern cannot be obtained.
[0047] The obtained specimens of pressure sensitive transferring adhesive tape are installed in transferring devices and the adhesive severability and adhesive strength are evaluated by three ranks; ◯Δ×. The obtained results are shown in Table 1.
[0048] In the evaluation of the adhesive severability, the factor that “to be cut at the intended point” is included.
[0049] According to the results of above mentioned Example and Comparative Examples, it has became clear that the poor cutting of the adhesive agent layer caused by the stringiness can be improved maintaining sufficient adhesive strength by above mentioned measures; namely, coating the adhesive agent of the adhesive agent layer over the surface of the substrate so as to form discontinuous island shape pattern, making the surface area of said one island to be from 1 to 100 mm 2 , further making the distance between adjacent islands to be from 0.1 to 4 mm.
TABLE 1 Example Comparative Example 1 1 2 3 4 conditions of size of an island 20 105 0.8 20 20 adhesive distance between 1 1 1 5 0.05 agent layer islands evaluation of adhesive ∘ x ∘ ∘ Δ ability severability adhesive strength ∘ ∘ x ∘ coating ∘ ∘ Δ ∘ x performance
Examples 2-7
[0050] Acrylic type polymers and hardeners shown in Table 2 are mixed together according to the following method and adhesive agent compositions are obtained.
[0051] A. Preparation of Adhesive Agent Composition
[0052] (1) acrylic type polymer
[0053] 100 parts of acrylic type polymer is mixed with solvent and poured into a flask, then heated to 65° C. under the flow of nitrogen gas and polymerized by adding an initiator.
[0054] (2) hardener
[0055] 2 parts of Coronate L (Product of Nihon Polyurethane Co., Ltd.) by solid part is added as a hardener to the polymer solution obtained by (1).
[0056] (3) adhesive agent composition
[0057] The viscosity and contents of involatile component of the adhesive agent composition are shown in Table 2.
[0058] B. Preparation of the Adhesive Agent Composition
[0059] Specimens are prepared using a coater for adhesive application equipped with a micro bar by which the clearance between a back up roller can be voluntarily adjusted. That is, the adhesive agent compositions obtained by above mentioned method are coated on the releasable treated surface of the embossed separator, then a PET film whose both surface are treated by releasable treatment is stuck and wound up so as to proceed the aging of adhesive agent.
[0060] After the aging process, the embossed separator is removed, slitting it by 1 cm width, and a backing wound type tape is prepared. The prepared tape is evaluated by test methods described in item C.
[0061] The embossed separator used above is prepared by using an embossed roll, the gap of convex part and concave part of which is 30 μm, using PET film of 38 μm thickness whose concave surface is treated by releasable treatment.
Comparative Examples 5-9
[0062] Specimens are prepared by same processes to Example 1 using adhesive agent compositions consisted of different components, having different content of involatile component and different viscosity as shown in Table 2 except using the same embossed separator having same embossed height (30 μm) to Examples. The adhering property to woodfree paper and the adhesive severability are measured.
[0063] C. The Measuring Method
[0064] The adhering property to woodfree paper and the adhesive severability of specimen obtained by Examples 2 to 7 and Comparative Examples 5 to 9 are measured.
[0065] (1) Adhering property to woodfree paper
[0066] A tape obtained by above mentioned method is stuck to the woodfree paper cut to 2 cm width. The releasable PET film is removed and the woodfree paper is stuck to, then pressed by go and back action of a roller of 1 kg weight. Just after the pressing, the woodfree paper is removed and the removing state is observed.
[0067] ◯; plucking of woodfree paper is observed in whole surface
[0068] ×; plucking of woodfree paper is not observed
[0069] (2) Adhesive severability
[0070] At the 5 cm point from the end of tape obtained by above mentioned method, a mark is put. The tape is extended to the mark and stuck to the woodfree paper of 2 cm width. The end of the releasable PET film of stuck part is released toward the vertical direction from the woodfree paper, and the severed state of the position 5 cm apart from the end is observed (refer to FIG. 2).
[0071] severability ◯; position less than 3 mm apart from the mark adhesive layer is severed
[0072] severability ×; more than 5 mm apart from the mark is necessary to be severed.
[0073] Obtained results are summarized in Table 2 and Table 3.
TABLE 2 Example 2 3 4 5 6 7 acrylic type blending parts 100 100 100 100 100 100 polymer amount hardener blending parts 2 2 2 2 2 2 (Corronate L) amount to solid part adhesive Involatile % 50 50 50 15 70 70 composition component pa · s/ 1 10 30 10 10 30 viscosity 25° C. height of emboss μm 30 30 30 30 30 30 coater clearance μm 90 90 90 170 75 75 adhesive convex * 1 μm 25 22 20 20 25 23 agent layer concave* 1 μm 11 11 10 15 4 3 ratio* 2 % 44 50 50 75 16 13 gel fraction % 40 45 48 60 30 35 adhesive severability ∘ ∘ ∘ ∘ ∘ ∘ adhering property to ∘ ∘ ∘ ∘ ∘ ∘ woodfree paper
[0074] [0074] TABLE 3 Comparative Example 5 6 7 8 9 acrylic type blending parts 100 100 100 100 100 polymer amount hardener blending parts 0 2 2 2 2 (Corronate L) amount solid part adhesive Involatile % 50 5 50 50 90 composition component pa · s/ 10 10 0.05 70 10 viscosity 25° C. height of emboss μm 30 30 30 30 30 coater clearance μm 90 440 90 90 60 adhesive convex * 1 μm 20 20 can can can agent layer concave * 1 μm 18 18 not be not be not be ratio * 2 % 90 90 coat- coat- coat- gel fraction % 0 70 ed ed ed adhesive severability x x (*3) (*4) (*5) adhering property to ∘ x woodfree paper
[0075] As clearly understood from the above mentioned results, the pressure sensitive transferring adhesive tape of excellent adhesive severability can be provided by a pressure sensitive transferring adhesive tape, comprising a substrate on which surface an adhesive agent layer is provided, the surface of said adhesive agent layer is characterized to have concave and convex shape, and the thickness of concave part is thinner than 80% of the thickness of convex part, further the gel fraction of said adhesive agent layer is bigger than 15% by weight.
Possibility to the Industrial Use
[0076] As mentioned above, the pressure sensitive transferring adhesive tape of excellent adhesive severability of the present invention can be provided by coating an adhesive agent layer by discontinuous island shape pattern or by coating an adhesive agent layer so as to have convex and concave shape maintaining excellent sufficient adhering strength. | The pressure sensitive transferring adhesive tape which transfers adhesive agent layer alone to an adherent is widely well-known, and in this case, the adhesive agent layer applied to a supporter has to be cut after it has been transferred to the adherent. However, since the adhesive layer is coated continuously, this type has a weak point that the adhesive agent layer causes problem of stringiness and stretching and cannot be cut smoothly. In the present invention, above mentioned weak points are dissolved by coating adhesive agent layer by discontinuous island shape pattern or by making the surface of adhesive agent layer to have concave and convex shape. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for playing a game with phonemes and letters to construct words and define their meaning.
2. Description of the Related Art
A number of games exist that utilize letters to build words. However, none of these games are based on phonemes or require the user to defend its meaning within a given topic. The use of phonemes permits greater flexibility and speed in the game. The game is flexible enough to permit its adaptation in any language.
SUMMARY OF THE INVENTION
It is one of the main objects of the present invention to provide a game that teaches the players how to combine phonemes and letters in a given language, or under a predetermined set of rules, to construct words and to form concepts.
It is another object of this invention to provide a game that injects knowledge to the users while they play without limit at all.
It is still another object of the present invention, when used as a language teaching tool, to provide a game for practicing the use of vocables to enrich the user's vocabulary.
Another object of the present invention is to bring within the reach of users of any age or cultural level the above mentioned benefits.
It is yet another object of this present invention to provide such a game that utilizes parts that are inexpensive to manufacture and maintain while retaining their effectiveness.
Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which:
FIG. 1 shows one of the storage carriers for the symbol chips that are preferably arranged in a predetermined order.
FIG. 2 represents one of the rectangular cards used in the preferred embodiment of the game having longitudinally extending slots where the chips with symbols are slidably positioned.
FIGS. 3 and 3A illustrate one of the topic chips used in the game having symbol on one of its faces and the other face having preferably a guide that cooperatively matches with the slots in the rectangular cards.
FIGS. 4 and 4A represent one of the symbol chips having a symbol represented on one of its faces and the other face having a relief pattern that cooperatively matches with the recessed patterns of the carriers.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, the present invention includes four rectangular cards 20 having each four longitudinally extending slots 22. Chips 30 and 40 are cooperatively and slidably received within slots 22. Topic chips 30 include a legend on one of its two surfaces that relates to a topic or other general class of things or general concept, and the other surface includes a guide that permits it to be slidably mounted to rectangular card 20. Symbol chip carrier 50 includes a number of recessed areas 144 for receiving symbol chips 40. Symbol chips 40 have two faces or surfaces. Upper surface 42 includes the representation of a symbol (such as a letter or phoneme or other figure that can be logically combine) and underside surface 44 has a relief pattern that mates with a complementary recessed pattern at a particular location in symbol chip carrier 50. In this manner, symbol chips 40 can be organized in a predetermined fashion to facilitate its readily localization by a player and to provide orderly means of storage. Also, this organization can respond to different degrees of difficulty that will permit the users or players to advance without getting frustrated.
To play the game a rectangular card 20 is given to each player. Preferably, there are four players and an arbiter. Each player is given twelve topic chips 30 and the player selects initially four of the twelve chips and slidably mounts each one of them on each one of the slots 22. Then the players decide who goes first and the order in which they are going to play.
The player that goes first selects one symbol chip 40 from carrier 50 and places it in one of the slots 22. The player must have a word in mind, and the word should not be obviously displayed because the other players may retrieve the symbols (phonemes or letters) that are required to complete the word. The second player will then take a chip 40, followed by the third and fourth player. When the turn for the first player comes again, he will try to finish the word he had to mind if the needed phoneme is still available. If a phoneme or letter is taken from carrier 50, the player may still change the intended word for another one, or may intend to construct a word for the other slots. The word formed has to be properly within the topic or otherwise it may be disqualified by the arbiter. It is also possible to negotiate or barter symbol chips 40.
After one of the players completes his four words, no more symbol chips can be taken from carrier 50. Then, each player has to define the meaning of each of his or her words and how they fall within the topics under which that were constructed.
The decision as to whether the words constructed fall within a given topic is within the jurisdiction of the arbiter. In the event there is no arbiter, then the players themselves will have to consult the pertinent references. Each player will receive a predetermined number of points for each work correctly constructed and defined.
The next step is to select another four topics by each of the players, and to proceed with the game in a similar fashion. Finally, the third round is the last one and after the first player completes his four words, the points accumulated are counted to determine who the winner is. If a player cannot support the meaning of a word constructed within a given topic then he or she will lose points accordingly.
One of the applications for this game is to use it to teach a language such as Spanish, for instance. In the application, the phonemes and letters are ordered in five groups, in the preferred embodiment. The first group includes phonemes that have a consonant followed by a vowel, such as:
______________________________________Series______________________________________ Sub-Group No. 1 1 ma me mi mo mu 2 pe po pa pu pi 3 la le li lo lu 4 sa se si so su 5 ta te ti to tu 6 ne ni no nu na Sub-Group No. 2 7 da de di do du 8 ca co cu que qui 9 ba bi bo be bu10 va ve vi vo vu11 rra rre rri rro rru12 ra re ri ro ru (rr) Sub-Group No. 313 ra re ri ro ru (r)14 fo fa fe fu fi15 jo ju ji ja je gi ge16 ga go gu gue gui17 no ne ni na nu18 cho chi cha chu che Sub-Group No. 419 lla llo llu lle lli20 ya yu yo ye yi21 zo ze zi zu za ci ce22 ha hi ho hu he23 ki ka ko ke ku______________________________________
The second group is characterized by having two consonants followed by a vowel.
______________________________________Series______________________________________ Sub-Group No. 524 pla ple pli plo plu25 blo bla ble bli blu26 cla cle cli clo clu27 flo fli fla fle flu28 glo gle gli gla glu Sub-Group No. 629 pre pro pra pri pru30 bra bre bri bro bru31 cre cri cro cra cru32 fre fri fro fru fra33 tro tru tra tre tri34 gri gro gra gre gru35 dra dre dri dro dru______________________________________
The third group has a vowel followed by one consonant.
______________________________________Series______________________________________ Sub-Group No. 736 al ul ol el il37 in on en an un38 as es is os us39 oz uz az iz ez40 er ir or ur ar Sub-Group No. 841 am em im om um42 ec oc ic ac uc43 ax ex ix ox ux44 id ed ad ud od______________________________________
The fourth group is composed of phonemes that include two vowel.
______________________________________Series______________________________________ Sub-Group No. 745 ia io ie iu46 ue ua ui uo47 au eu Sub-Group No. 848 ai ei oi49 ae ao50 ea eo51 ay uy oy ey______________________________________
The fifth group includes the letters of the alphabet, preferably the letters are placed in alphabetical order in symbol chip carrier 50. It should be noted that the groups have been formed taking in to consideration the difficulty or simplicity of its pronunciation in Spanish language. The number of repeated phonemes and letters will vary depending on the frequency with which the phonemes or letter are used in the language. At least there will be one phoneme and one letter of each of the ones included the foregoing five groups.
__________________________________________________________________________Carrier Number 1a e o u i u a me M mi m momi mu ma me mu m mis mo mami ma mas po pa pe pi pupa pi P p pu A E I O UCarrier Number 2le lo l la li L los li las lelu lo la li l la si se sa ssu so S sa s su T ti ta tte tu to ta tu ti nu no nCarrier Number 3na ni ne no ni na nu uno Ndo di da du de d D cu quico qui ca que q Q co ca coque x X bi be bu ba bo buCarrier Number 4B b vi ve va vu vo v V rrrru rre rri rro rra ra riro ru re ra ri ra r ro Rfe fi fu fa fo fe fa f F GCarrier Number 5gi ge ji je jo ju ja J ji jgo gui gue gu ga G ni nuna ne no N n chi cho chech cha chu cho CH llu ellaCarrier Number 6lla lle llo lli ll Ll Y yiYo yu yo y ye yo ya z zeza zi zu zo Z zo ci ce cci ce C hi he h hu ho hi Carrier Number 7H hu ha ko ku ki ke k Kka a A b B c C ch CH d De E f F g G h H i I j Jk K l L ll Ll m M n N n NCarrier Number 8o O p P Q r R rr s St T u U v V w W x X y Yz Z pla ple plu plo plipla bla blu blo bli bleCarrier Number 9cle clu clo cla cli floflu fla fle fli gla gloglu gli gle glu pri prupra pre pro bre bru briCarrier Number 10bra bro bri bru cri crucre cro cra cro cra frofri fru fra fre fri trotre tra tri tru tro treCarrier Number 11gre gro gra gru gri dradro dru dre dri a b c chd e f g h i j k l ll m n op q r rr s t u v w x y zCarrier Number 12el il ul el ol el ul El alel un en sin an in un on anun en on in os es as nos usis es is as us az oz uz izCarrier Number 13ex iz ar er por ir or ur era r am om um im em om am emic ec oc ac uc ex ax ix oxux ud od ad ed id ie io iaCarrier Number 14iu ia ie io ua uo ue ua uieu au ou au eu oe oa oi eiai ao ae ea eo uy ey ay oyob ab ub ! ? ! ? ! , . .__________________________________________________________________________
As it can be seen, the phonemes in Spanish follow a predetermined order that responds to its complexity in pronunciation. This is specially useful with children, including those with disabilities, so that increasingly complex words can be formed with the combination of the phonemes. In addition, the player or user has to defend the meaning of the word resulting from the combination of words and that if falls within the topic slot where it was formed.
The game apparatus described herein can also be implemented with computerized video technology wherein icons of different shapes can be created to perform substantially the same functions of the components we have described here.
The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense. | A game for building words and form concepts form the selection and arrangement of symbols within a given topic. A card with longitudinal slots is adapted to receive one topic chip per slot and one or more symbols that form a word related to each one of those topics. The symbols chips are pre-organized through the use of unique relief patters that are accepted in position with complementary relief patterns in a carrier for these symbol chips. As the players build their words they are called to defend them as being relevant to the topic categories where they were built. | 6 |
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a method for rapidly producing in high yield a single sterol glycoside from a mixture of sterol glycosides which originates in natural substances. The sterol glycosides obtained from the present invention have a hemostatic effect and a blood vessel-reinforcing effect and are also useful as a pharmaceutical.
As is already broadly known, the sugar constituent of naturally occurring sterol glycosides is generally glucose, while the sterol constituent usually involve a plurality of extremely similar structures of free sterols which are naturally existent.
Even in the case where it was reported in the past that substances obtained from certain plants were existent in the form of a single sterol glycoside, it has been found a result of gas chromatography-mass spectrometry analysis (hereinafter abbreviated to GC-MS), that these substances invariably contain different kinds of sterol glycosides. Since sterols of sterol glycosides have extremely similar structures, as mentioned above, purification methods such as recrystallization method, various kinds of liquid chromatography, precipitation reactions with alkali metal salts, etc., have only made it possible to separate a mixture of sterol glycosides from other substances in admixture therewith. These methods have not permitted separation of sterol glycosides from each other. Thus, it has been regarded to be difficult to separate a mixture of natural sterol glycosides from each other so as to obtain a pure sterol glycoside, even in small amounts. The present invention provides a separation method according to which it is possible to obtain single sterol glycoside from a mixture of sterol glycosides which originates in natural substances, in a high purity and on a commercial scale.
The present invention will be described below in detail in the order of its procedure.
(1) Selection of raw material
In order to separate and obtain a desired sterol glycoside with certainty, in a high purity and with a high yield, it is necessary to correctly determine the kinds and proportions of the respective constituents of a mixture of sterol glycosides in a raw material, because, even when liquid chromatography as discussed below is applied, the resulting separation has of itself a limitation. Hence it is necessary to select, at the stage prior to the liquid chromatography, a raw material containing no other kinds of sterol glycosides which are difficult to separate from the desired sterol glycoside. Mixtures of sterol glycosides which originate in natural substances are intrinsic of the kinds of said natural substances, and also the kinds and the constitution proportions are infinitely varied and distributed. Accordingly, notwithstanding the separation according to the liquid chromatography as mentioned below has a limitation, it becomes possible to isolate all-kinds of sterol glycosides from natural substances, by selecting an adequate raw material.
Depending on the desired sterol glycoside, a detailed analysis of sterol glycosides with a number of raw materials is necessary to identify a raw material which is actually suitable for the purpose. The present inventors have established a method for determining the kinds and proportion of sterols constituting sterol glycosides in a raw material, in a simple manner, correctly and in a short time, and thus have solved this problem.
The method for selecting a raw material is based on such the finding that the kinds and proportion of free sterols which are always coexistent in an objective sample which originates in natural substances accord well with those of sterol glycosides. Heretofore, for example, the analysis of a mixture of sterol glycosides in a plant has been studied through a procedure of firstly extracting a mixture of sterol glycosides, separating and purifying it, thereafter subjecting it to acid decomposition in an alcohol, and analyzing the resulting free sterols. However, such a method not only has been cumbersome in the operation and has required a long time, but also has had a decisive drawback in that, in case of certain kinds of sterols, decomposition thereof occurs during the process of acid treatment, while, in the case of other sterols, isomerization occurs, hence making it impossible to correctly grasp sterol glycosides which are really present. For example, Δ 24 (28) sterols, which are naturally broadly distributed, change into compounds having a double bond dislocated, as shown below. ##STR1##
Thus, results from which it has seemed as if a difference were present between free sterols and sterol glycosides in the same kind of plant, have often been reported. However, as mentioned below, according to the direct analytical method developed by the present inventors, a correct comparative study on both of the sterols has become possible, and from the results of studies with a number of plants, it has been clearly confirmed for the first time that the kinds and the constitution proportion of both of the sterols accord well. With regard to raw materials obtained from wheat, etc., examples thereof are shown in Table 1.
TABLE 1______________________________________Comparison of sterols constituting free sterols with thoseconstituting sterol glycosides 24-Campe- Stigma- β- Methylene- Avena-sterol sterol sitosterol cholesterol sterol______________________________________Wheat f. 22% --% 72% 1% 5% G. 20 -- 75 1 4Rice f. 18 15 63 1 3 G. 15 17 65 0.5 2.5Corn f. 23 7 66 1 3 G. 20 9 68 1 2Soy- f. 22 20 54 1 3bean G. 23 19 55 1 2Kapok f. 9 8 80 0.5 2.5 G. 10 9 78 0.5 2.5Cotton f. 4 -- 95 -- 1seed G. 4 -- 95 -- 1Coffee f. 20 21 54 1 4bean G. 17 22 57 1 3______________________________________ (f.represents free sterols and G. represents sterol glycosides.)
The analysis of free sterols does not require any particular treatment such as acid decomposition, etc., as compared with the case of sterol glycosides. In addition, a precise analysis is possible with a small amount of sample, without any particular purification, by means of GC-MS, etc., in a short time, and hence it is possible to soon judge, based on the analytical results of the free sterols, whether the sterol glycosides to be isolated are suitable or not as a raw material. In practice, as for the decision of whether they are suitable or not as raw material, it becomes a standard of the judgement whether Δ 5 - and Δ 7 -sterol glycosides are in admixture or not. For example, in case where isolation of Δ 5 -sterol glycosides is desired, a raw material containing almost no Δ 7 -sterol glycosides should be selected, while, in case where isolation of Δ 7 -sterol glycosides is desired, a raw material containing no Δ 5 -sterol glycosides, such as a number of plants belonging to cucurbitaceae, etc. should be selected.
In case of plants whose sterol compositions have already be sufficiently studied, it is possible to make use of the results as a material for selecting a raw material, but, in case of the present invention wherein isolation of high purity sterol glycosides is aimed, different kinds of sterol glycosides which are difficult to separate should not be present even if their amount is 1% or smaller, and even in case of isolation of representative sterol glycosides illustrated in Examples mentioned below, raw materials have been strictly selected according to the above-mentioned means to achieve the object.
Next, in case where raw materials are taken into account from an economical viewpoint, all raw materials which originate in natural substances and have been presently dealt on a commercial scale are utilizable, and a number and a variety of other substances which are readily available, such as products, oil seed extraction cakes, useless disposal portions, by-products, etc., can be utilized.
(2) Separation of mixture of sterol glycosides and acetylation thereof
Separation of mixture of sterol glycosides from a raw material can be carried out according to known methods, and it is also possible to easily obtain them in a high purity according to a specific precipitation reaction between sterol glycosides and an alkali metal carbonate in a lower alcohol disclosed by the present inventors (Japanese Patent application No. 9996/1975). Although sterol glycosides are difficulty soluble in generally used organic solvents, handling large amounts thereof by means of a number of organic solvents becomes possible by acetylating them into their tetraacetates in a conventional manner, and also it is possible to extend the kinds of mobile phases in liquid chromatography.
(3) Separation of mixture of sterol glycoside tetraacetates by means of liquid chromatography
As already described above, there has heretofore been no effective means for separating mixture of sterol glycosides from each other, and separation thereof has been very difficult, but the present inventors, as a result of preliminary studies, have found a means for separating sterol glycoside from each other according to a liquid chromatographical method, and attempted to separate mixture of sterol glycoside tetraacetates according to a liquid chromatography under various conditions. As a result, it has been clarified that stationary phases which are effective for the separation, silica gel silver nitrate-impregnated silica gel, magnesium oxide, alumina, Florisil, etc. exhibit a separating capability to the same extent as that in case of separation of free sterols, and in case of sterol glycosides, too, the separation is very effectively carried out based mainly on the difference in the structures of constituting sterols.
The above-mentioned stationary phase can be employed for the separation of sterol glycosides in all the same manner as in the case where it has so far been applied to free sterols, by selecting a suitable mobile phase solvent.
The present inventors have further made studies on separating conditions which are more practical and hgher in the performance, and as a result, have established a separating method according to a high performance liquid chlormatography (HPLC) wherein a stable microfine silica gel-ODS (a material obtained by chemically bonding octadecyl group to silica gel) is employed as a stationary phase and a single solvent such as methamol, acetonitrile, etc. is employed as a mobile phase. Thus it has become possible for the first time to isolate cholesterol glucoside, brassicasterol glucoside, campesterol glucoside, stigmasterol glucoside, β-sitosterol glucoside and Δ 7 -sterol glycosides and reduction substances, etc. corresponding thereto, from mixtures of sterol glycosides which originate in natural substances, such a separation having been impossible according to other methods. An example of the HPLC chromatogram of sterol glycoside tetraacetates obtained from soyalecithin under these conditions is shown in FIG. 1.
Further, this separation according to HPLC is furnished with all advantageous conditions necessary for scale-up, and a production on a commercial scale is also possible.
(4) Deacetylation
When the resulting single sterol glycoside tetraacetate is subjected to an alkaline alcohol treatment in a conventional manner, a deacetylated, difficultly soluble sterol glycoside quantitatively precipitates from the alcohol and it is possible to easily obtain an objective pure sterol glycoside.
Next, isolation of three kinds of sterol glycosides which are most abundantly present in nature will be described in Example 1, and an example of separation of slightest amounts of sterol glycosides will be described in Example 2.
EXAMPLE 1
Isolation of β-sitosterol glucoside (I), stigmasterol glucoside (II) and campesterol glucoside (III)
Free sterols contained in acetone-extracts from about 10 kinds of plants were analyzed according to GC-MS, and plants containing almost no Δ 7 -sterol-glycoside, such as kapok seed, soybean, olive, corn and wheat, etc. were selected as raw materials suitable for isolation of (I); potato contining amost no (III) which is difficult to separate according to HPLC was selected as a raw material suitable for isolation of (II); and wheat germ containing almost no (II) was selected as a raw material suitable for isolation of (III).
These raw materials are each treated according to the following procedure which is common thereto:
A defatted and dried raw material is extracted twice with acetone in an amount of twice volume based on the weight of the raw material, and then acetone is distilled off. 10% KOH methanol in an amount of 20 times volume based on the weight of the residue is added. After reflux for one hour, K 2 CO 3 is added till saturation is a attained, and successively reflux is carried out for 3 hours. The resulting precipitate is washed with methanol and then with water and dried to obtain a mixture of high purity sterol glycosides, which are then converted to their tetraacetates with acetic anhydride in pyridine in a conventional manner. The tetraacetates are employed as samples for separation according to HPLC. Conditions of HPCL are as follows:
Stationary phase: Silca gel-ODS (5μ) (column, 10 mmφ×30 cm)
Mobile phase: acetonitrile (flowrate, 10 ml/min)
Under these condition, the amount of sample once treated is 0.1 g and the time required is within 10 minutes. In such once separation, the objective substance could be completely isolated from each sample without any loss of the substance. Tetraacetates corresponding to the resulting isolated (I)-(III) are collectively described in Table 2 together with those obtained in Example 2.
By hydrolyzing the tetraacetates with 5% KOH methanol, sterol glycosides quantitatively precipitated from methanol and pure sterol glycosides could be easily obtained.
EXAMPLE 2
Separation of 24-methylenecholesterol glycoside (IV) and avenasterol glycoside (V)
(IV) and (V) are generally present in mixtures of sterol glycosides as a small amount component. In this Example, a commercial soyalecithin was employed as a raw material, and sterol glycosides were separated therefrom, utilizing a precipitation reaction with K 2 CO 3 in methanol (said Japanese Patent Application No. 9996/1975), and purified and further turned into tetraacetates, to prepare separation samples (IV) and (V). (IV) and (V) contained therein can be separated by direct by applying HPLC, but the resulting efficiency is inferior. Thus they were subjected to a column chromatography employing a silver nitrate-impregnated silica gel as a stationary phase, and main sterol glycosides (I)-(III) initially flowing out were removed to obtain a mixture consisting mostly of tetraacetates of (IV) and (V), alone, which were then employed as samples for HPCL. In the separation according to the column chromatography with a silver nitrate-impregnated silica gel, a 20% silver nitrate-impregnated silica gel (4 cm×40 cm) was employed as a stationary phase and chloroform/cyclohexane (5:1) were employed as a mobile phase solvent, and once 5 g of a sample was treated to obtain about 1 g of a mixture of tetraacetates of (IV) and (V) from 25 g of the sample. Next, employing this mixture as a sample, separation accroding to HPCL was carried out under the conditions of Example 1 to separate (IV) and (V) from each other.
In addition, according to purity assay through HPLC and GC, it was confirmed that a product having a purity of 99% or higher was obtained for (IV) and a product having a purity of 97% or higher was obtained for (V). Separated tetraacetates are summarized in Table 2. Separated tetraacetates were simply deacetylated with 5% KOH-methanol, and the corresponding amounts of sterol glycosides precipitated quantitatively.
TABLE 2__________________________________________________________________________Observed values of isolated tetraacetates Elemental analysis (upper, lower,Isolated observed value; calculated value) Purity throughSubstance Yield (g)* Melting point(C°) C, H HPLC and GC__________________________________________________________________________ 69.48 9.31β-sitosterol 175-177 99 or higher %glucoside 69.32 9.20 69.60 8.91Stigmasterol 0.40 128-130 99 or higher %glucoside 69.54 8.89 68.97 9.29Campesterol 0.18 172-174 99 or higher %glucoside 69.01 9.1024-Methylene- 69.03 8.98cholesterol 0.41 166-168 99 or higher %glucoside 69.23 8.80 69.32 9.14Avenasterol 0.48 181-183 97 or higher %glucoside 69.54 8.89__________________________________________________________________________ *Yield obtained by treating lg of sample through HPLC
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 represents a high performance liquid chromato-gram of sterol glucoside tetraacetates of soyalecithin. The abscissa represents the eluting time and the ordinate represents the height of the peaks. Silica gel-ODS (4 mm×30 cm) was employed as column; the amount of sample pourred in was 10 mg; acetonitrile was employed as mobile phase; the pressure was 50 kg/cm 2 ; the flow rate was 1.3 ml/min; a refractometer was employed as detector; and the measurement temperature was 25° C. Peak 1 represents 24-methylenecholesterol glucoside tetraacetate; numeral 2, avenasterol glucoside tetraacetate; peak 3, stigmasterol glucoside tetraacetate; peak 4, campesterol glucoside tetraacetate; peak 5, β-sitosterol glucoside tetraacetate; and peak 6, stigmastanol glucoside tetraacetate, respectively. | A method for producing high purity sterol glycosides which is characterized by selecting a most suitable raw material from among raw materials, by making use of free sterols coexistent in said raw materials, as an indication for the selection; extracting a mixture of sterol glycosides from the selected raw material; turning the resulting extract into their tetracetates; thereafter separating an objective fraction alone according to a liquid chromatography; and hydrolyzing this fraction to obtain the original sterol glycosides. | 2 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] Embodiments of the present invention relate to U.S. Provisional Application Ser. No. 61/992,778, filed May 13, 2014, entitled “AIR DEFLECTOR”, the contents of which are incorporated by reference herein and which is a basis for a claim of priority.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] Embodiments of the present invention generally relate to heating, ventilation and air conditioning (HVAC) improvements including modifiable air deflectors and more specifically to an improved air deflector capable of moving in relation to changing air patterns, ceiling heights and inhabitants preferences.
[0004] 2. Related Art
[0005] In prior art models of air deflectors an axle is placed in a fixed position and the air deflector is only capable of rotating around the fixed axle. Thus the air deflector is merely opened to various degrees from a pivot on the fixed axle. The prior art is limited to allow for any true customization and therefore an HVAC technician is forced with the decision carry a variety of air deflectors with them for variable jobs, or to just place a non-optimal air deflector in many cases where some vents are at different locations than others on the same job.
[0006] In contrast, the present embodiments relate to an improved air deflector apparatus that allows for the deflector to be adjusted for pivoting the deflectors but also to change the distance between the pivot point merely by sliding a damper guide along rails thus being further adaptable to the air pattern demands in a specific area.
SUMMARY OF THE DISCLOSURE
[0007] This invention is based on creating a uniform built air deflector system that can be adjusted in the field to highly variable air pattern conditions. The axle of the air deflector is moving along the spacers. Wherein in the prior art models the air deflector axle is fixed and the air deflector is only capable of rotating around the axle.
[0008] When air flows through a venting system to either heat or cool a home or business the air is still subject to the properties of resistance and temperature associated with the air molecules. For instance, when running hot air through a vent that is in a ceiling, because hot air naturally rises and cold air does not, if the warm air leaving a vent is not pushed far enough out of the vent, down to the floor area, where the cooler air (and inhabitants) are very little effect will be felt at the lower areas. In such cases the warmer air will just accumulate along the ceiling area and will have trouble mixing with the cooler air found further below the vent. In order for best air mixing results to occur the air leaving the vent must have enough push behind it to allow it to travel to the distance required for proper mixing. For a standard ceiling at about 8 to 10 feet, the push only needs to be about 5 to 8 feet for the inhabitants to feel the flow and to allow the mixing of the airs. However, for a higher ceiling 15 to 20 feet high the push needs to be about 10 to 18 feet to provide most efficient air mixing and best occupant relief.
[0009] When cooling a room there is a need to provide enough air flow to push the cooler circulating air to where the inhabitants are as well, and for the same reasons the amount of push and the height desired by the occupants can be highly variable based upon the individual desires of the inhabitants. Additionally, whereas some inhabitants will want to feel the air flow on them for relief (like air from a fan), others will not want the air flow to directly reach their level and possible blow their papers or materials around and will only want the surrounding ambient air to be modified about them in a non-stream like or flow type way.
[0010] The embodiments of the present invention encompass an air deflector that may be manufactured in such a way that it can be modified in the field to address the variable demands of the individual job site and its inhabitants preferences. An advantage to this is that, instead of having to carry a variety of deflectors in their truck and running the risk of having the wrong deflector for the job, the HVAC technician can carry the embodied highly modifiable air deflector system that can be modified at point of use to reflect the air push demands of the individual vent placement and to the inhabitants preferences.
[0011] The embodied air deflector system comprises side frames which hold spacers or guide rails which allow for a damper guide with a pin holder spot to hold a pin that extends from the pin holder portion of a damper guide through a slot on a air deflector/damper and ends in a companion pin holder spot in another damper guide placed between spacers on the opposite end of the air deflector. The air deflector is held in place on both sides by the pin which serves as an axle within the damper guide and allows for the angle of the air deflector to be adjusted along the axle and fixed in place, but further fully adjustable upon request. Additionally the damper guide is situated between the spacers in such a way that the damper guide can be slid along a plane such that the spacers serve as a type of rail for the damper guides to be allowed to adjust at varying positions along the plane. This enables the axle which serves as a pivot point for the air deflector to be modified in such a way that when two opposing damper guides are placed in close proximity along the rails the deflectors are naturally in very close proximity and if angled towards each other one can get a very narrow opening for the air to push through. In these cases much like a nozzle on a water hose the air passing through will throw to a further distance away from the vent then it would if the deflectors were angled away and/or the damper guides were placed further from each other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 illustrates of a side view of an embodied deflector system.
[0013] FIG. 2 illustrates a building schematic of an embodied deflector system when placed within the other components of an HVAC system.
[0014] FIG. 3 illustrates a perspective view of an embodied deflector system.
[0015] FIG. 4 illustrates a bottom perspective view of the embodied deflector system of FIG. 3 .
[0016] FIG. 5 illustrates a side perspective view of the embodied deflector system of FIGS. 3 and 4 .
[0017] FIG. 6 illustrates a side perspective view of the embodied deflector system of FIGS. 3-5 .
[0018] FIG. 7 illustrates a building schematic view with an embodied deflector system in place in and connected into an HVAC system, additionally airflow currents are shown in relation to the air deflector system.
[0019] FIG. 8 illustrates air flow through a deflector system wherein the deflectors are angled towards each other and thus the air is funneled through the narrower opening and forced to a further distance because of back pressure of air molecules behind.
[0020] FIG. 9 illustrates air flow through a deflector system where the deflector blades are angled towards the same side thus channeling the air to circulate in a specific direction.
[0021] FIG. 10 illustrates air flow through a deflector system wherein the deflectors are wide open and very little resistance or channeling of the air is done and thus the amount of push from the back pressure of the air molecules is minimal.
[0022] FIG. 11 illustrates air flow through a deflector system wherein the deflectors are angled towards each other and are thus in a more closed position, thus the air molecules have more back pressure and are thrown further once they escape through the deflector channel.
[0023] FIG. 12 illustrates air flow through a deflector system wherein the one deflector is angled inward more versus another deflector is wide open, thus allowing some air flow to be deflected in a specific direction.
[0024] FIG. 13 illustrates air flow through a deflector system wherein the deflectors are moved in close proximity to one another by moving both damper guides towards a center position along the guides.
[0025] FIG. 14 illustrates air flow through a deflector system wherein the deflectors are maintained at a similar angle to each other as shown in FIG. 13 , but the deflectors are moved in distal proximity to one another by moving both damper guides towards the end position of each rail or spacer guide.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] The embodied universal vent system/air deflector is capable of adapting to height of any placement by allowing the dampeners to slide within the vent so that they can determine the throw of the air from the vent. For a vent in an elevated ceiling there is a need to get the air from the vent a further distance in order to have a positive effect on the residents in the house.
[0027] For the purposes of the present invention the “throw” of the air from the vent is meant to mean the approximate distance the air molecules first travel upon exiting the vent chamber and starting to mix with the ambient air. It is most closely related to the spray distance of water out of a hose or sprinkler.
[0028] The throw of the air is affected by the pressure behind it when exiting the vent system much like the spray of water out of a hose nozzle. If the nozzle is very narrow the spray goes far, if the nozzle is not narrow the water merely runs out. The spray of water much like the throw of air can also be affected by how high the hose is turned on.
[0029] Thus, in order to minimize the need for a HVAC system to be turned on high to get the air where it needs to go, by using the right air deflector one can allow the HVAC system to remain constant while adjusting the amount of deflection to throw the air to the necessary distance for the job.
[0030] The vent system embodied can be installed at various heights and adjusted accordingly to the demands of the needs to throw the air to a certain distance.
[0031] The embodied air deflector system 1 as referenced in FIG. 1 , comprises side frames 2 which hold spacers or guide rails 4 which allow for a damper guide 6 with a pin holder spot in the form of a pin placement hole 8 to hold a pin 10 that extends from the pin holder portion 8 of a damper guide 6 through a damper or deflector slot 14 on a air deflector/damper 12 and ends in a companion pin holder spot 8 in another damper guide 6 placed between spacers 4 on the opposite end of the air deflector 12 . The air deflector 12 is held in place on both sides by the pin 10 which serves as an axle 11 within the damper guide 6 and allows for the angle of the air deflector 12 to be adjusted along the axle and fixed in place, but further fully adjustable upon request. Additionally the damper guide 6 is situated between the spacer rails 4 in such a way that the damper guide 8 can be slid along a plane such that the spacers 4 serve as a type of rail for the damper guides 8 to be allowed to adjust at varying positions along the plane. This enables the axle 11 which serves as a pivot point for the air deflector 12 to be modified in such a way that when two opposing damper guides 6 are placed in close proximity along the rails 4 the deflectors 12 are naturally in very close proximity and if angled towards each other one can get a very narrow opening through the damper blades 16 for the air to push through. In these cases much like a nozzle on a water hose the air passing through will throw to a further distance away from the vent then it would if the deflectors 12 were angled away and/or the damper guides were placed further from each other.
[0032] As referenced in FIG. 2 an embodied deflector system 1 is shown installed into an HVAC system 18 and attached to the ceiling infrastructure 20 . Airflow is provided through the HVAC system 18 which exits out through an embodied deflector system 1 that is attached to ceiling structure 20 . The embodied deflector systems are then able to adjust to the conditions of the room to which air flow is desired. For example if the ceiling infrastructure is high off the floor it is more likely that more throw from the deflector system 1 will be necessary to adequately mix the air at the top of the room with the air at the bottom of the room. In this case either the HVAC system would be turned up higher to provide more air pressure and thus more throw, or the deflector system can be narrowed to increase air pressure by creating a back flow resistance and funneling effect. The embodied deflector system shown is highly modifiable to the architecture and comfort demands of a room, and does not require the increase in energy required in turning up the HVAC system.
[0033] As referenced in FIGS. 3-6 an embodied deflector system 1 includes side frames 2 connected by spacer rails 4 which allow for the damper guides 6 to slide back and forth along the rails 4 . The damper guides further have a pin placement hole 8 for placing a pin 10 . This pin 10 within the pin placement hole 8 serves as an axle or pivot point 11 for the dampers 12 to be angled within the system. The pin 10 extends from the pin placement hole on the damper guide 6 through the damper 12 via a damper slot 14 . The angle of the damper 12 and thus the placement of the damper blade 16 can be determined by pivoting the damper along the pivot point into the desired location. Additionally, the damper guides 6 can be places in close proximity or distally from each other along the rails 4 to further determine and modify the air flow. Whereas, FIG. 3 shows the above in a side perspective type view; FIG. 4 shows the above from a bottom perspective view; FIG. 5 shows the above from a side perspective view; and FIG. 6 shows another top side perspective view of the above wherein the deflectors 12 are shown in a closed position wherein the ends of the deflector blades 16 are in contact with one another.
[0034] FIG. 7 illustrates a building schematic view with an embodied deflector system 1 in place in and connected into an HVAC system 18 , additionally airflow currents are shown in relation to the air deflector system 1 .
[0035] FIGS. 8-14 illustrate the effect the damper angles and damper location on the rails 4 effect the air flow. For example in FIG. 8 the deflectors 12 are angled towards each other and thus the air is funneled through the narrower opening and forced to a further distance (throw) because of back pressure of air molecules behind.
[0036] FIG. 9 exemplifies how the air flow through a deflector system 1 where the deflectors 12 are angled towards the same direction and thus the deflectors 12 channel the air to circulate in a specific direction.
[0037] FIG. 10 illustrates how the air flows through a deflector system 1 wherein the deflectors 12 are wide open and there is very little resistance or channeling of the air and thus the amount of push from the back pressure of the air molecules is minimal.
[0038] In contrast, FIG. 11 illustrates how the air flows through a deflector system 1 wherein the deflectors 12 are angled towards each other and are thus in a more closed position, thus the air molecules have more back pressure and are thrown further once they escape through the deflector channel.
[0039] FIG. 12 exemplifies how air flows through a deflector system 1 wherein the one deflector 12 is angled inward more versus another deflector 12 is wide open, thus allowing some air flow to be deflected in a specific direction.
[0040] FIG. 13 shows how the air flows through a deflector system 1 wherein the deflectors 12 are placed at a slight angle and the deflectors 12 are moved in close proximity to one another by moving both damper guides 6 towards a center position along the guides 4 . Whereas, FIG. 14 illustrates how air flows through a deflector system 1 wherein the deflectors 12 are maintained at a similar angle to each other as shown in FIG. 13 , but the deflectors 12 are moved in distal proximity to one another by moving both damper guides towards the end position of each rail or spacer guide 4 . Thus by maintaining the deflector angle but changing the position of the deflector 12 on the guide the air flow is significantly changed. | Enclosed is information related to heating, ventilation and air conditioning (HVAC) improvements including modifiable air deflectors and more specifically to an improved air deflector capable of moving in relation to changing air patterns, ceiling heights and inhabitants preferences. More specifically the present disclosure relates to an improved air deflector apparatus that allows for the deflector to be adjusted for pivoting the deflectors but also to change the distance between the pivot point merely by sliding a damper guide along rails thus being further adaptable to the air pattern demands in a specific area. | 5 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to the continued exploration of Pythium insidiosum, its use as an antigen for prophylactic and therapeutic vaccines and to isolation methods for it. In prior inventions of Dr. Alberto L. Mendoza and other co-inventors with him P. insidiosum protein was used for treatment of P. insidiosum infection in humans and other animals, see for example, U.S. Pat. No. 5,948,413 of Sep. 7, 1999; U.S. Pat. No. 6,287,573 of Sep. 11, 2001; and U.S. Pat. No. 6,833,136 of Dec. 21, 2004. In each instance, the fungal-like strain there used was eventually used either alone or with other cells to treat Pythiosis, both in humans and other animals.
[0002] The particular fungal-like strains there used were deposited in the American Type Culture Collection under the Budapest Treaty as ATCC 74446 and/or ATCC 58643. The animals treated in those patents included humans, horses, dogs and cats. In every instance in each one of these patents an objective was to prepare a vaccine from Pythium insidiosum to provide a beneficial immunological response for treating or preventing Pythiosis. The disclosure of U.S. Pat. Nos. 5,948,413; 6,287,573; and 6,833,136 are incorporated herein by reference.
[0003] Dr. Mendoza and his colleagues have continued working with P. insidiosum in an effort to improve upon the inventions of their earlier patents. Improvement can come in a variety of ways when dealing with vaccines. One way of improvement is in the effectiveness of specific disease treatment or prevention. Another way to improve is to widen the scope of diseases that can be effectively treated or prevented with a vaccine. A still further way to improve a vaccine is to widen the number of species that can be treated with it. The present invention has as its primary objective both widening the number of species that can be treated with P. insidiosum protein and widening the scope of diseases that can be effectively treated by modulating the immune response in an animal.
[0004] It goes without saying that there is a continuing need for vaccines that are effective and provide an efficient modulated immune response to effectively treat a variety of diseases in a variety of different species.
BRIEF SUMMARY OF THE INVENTION
[0005] The present invention provides a pythium immunotherapy produced from Pythium insidiosum Strain MTPI-04 (Texas strain) by isolation and concentration of soluble proteins. This strain-specific pythium immunotherapy is comprised of all proteins found in Pythium allergenic extract (PAE) described in Dr. Mendoza's earlier patents, but additionally contains various other proteins, including a significantly greater quantity of 28 kDa protein expressed by MTPI-04. In short the expressed protein profile is quite different in this case.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0006] This invention relates to a pythium immunotherapy product which may be administered by injection, for example.
[0007] As used herein, Pythium insidiosum Strain MTPI-04 (Texas strain) refers to Strain MTPI-04 or any variant or derivative or analog strain thereof which produces an equivalent immune modulating effective response; that is a response that can be used to provide a pythium immunotherapy demonstrated benefit for treatment of, or managing diseases other than caused by Pythium insidiosum, such as for example: Sarcoid (Equine); Mast cell tumor (Canine); Allergic Disease (Canine, Feline, Equine, Human); Inflammatory Bowel Disease (Canine); Miliary dermatitis (Feline); Exuberant Granulation (Equine); Chromoblastomycosis (Human); Asthma (Feline); Otitis Externa (Canine, Feline); Arthritis (Canine); Anhidrosis (Equine); and Navicular Disease and Laminitis (Equine).
[0008] It is not known what is peculiar and unique about the P. insidiosum Strain MTPI-04 (Texas strain) that allows it to effectively modulate immune systems, and provide immunotherapy for diseases beyond those caused by Pythium insidiosum. While Applicant does not wish to be bound by any theory, it is possible that the other proteins expressed than those expressed by the strains used in our earlier patents, and/or that the different ratios of protein may be factors. For example, it has been observed that there is a significantly greater quantity of 28 kDa protein, and that the expression of a protein at approximately 124 kDa appears to be unique to Strain MTPI-04 (Texas strain). See Chindamporn et al., Clinical Vaccine Immunology, Antibodies in the Sera of Host Species with Pythiosis Recognize a Variety of Unique Immunogens in Geographically Divergent Pythium insidiosum Strains, Vol. 16, No. 3, pp. 330-36, Table 3 MTPI-04 at page 334.
[0009] With regard to P. insidiosum, Strain MTPI-04, Applicants assert that upon allowance of claims, Applicants will deposit P. insidiosum, Strain MTPI-04, as described in this originally filed specification, and will amend claims as necessary insert the ATCC number into the claims. Applicants further provide assurance that:
a) during the pendency of this application access to the invention will be afforded to the Commissioner upon request; b) all restrictions upon availability to the public will be irrevocably removed upon granting of the patent; c) the deposit will be maintained in a public depository for a period of thirty years, or five years after the last request for the enforceable life of the patent, whichever is longer; d) a test of the viability of the biological material at the time of deposit will be conducted (see 37 C.F.R. §1/807); and e) the deposit will be replaced if it should ever become non-viable.
Applicants submit this offer of deposit completes requirements of 35 U.S.C. §112 with respect to Pythium insidiosum, Strain MTPI-04, and all requirements of 37 C.F.R. §§1.801-1.809 are met.
[0015] While the hereinafter description is given primarily in conjunction with injectable vaccines in sterile aqueous solution, the vaccine can be administered in other ways such as needle-less injection, a solid dose implant, topically or even by oral, ocular, inhalation or suppository administration.
[0016] The process of producing the vaccine begins by growing cells of Pythium insidiosum Strain MTPI-04 in a culture medium. The preparation of the stock culture, seed inoculums and finished product can occur in the following manner. For convenience the steps are categorized and numbered.
Growth of Cultures
[0017] 1. Cultures of Strain MTPI-04 are stored/maintained in either of the following three (3) forms:
a. Lyophilized b. Frozen c. Hyphae culture maintained on Corn Meal Agar (CMA) or Sabouraud Dextrose Agar (SDA)
[0021] 2. An SDA plate is inoculated with one of the above and incubated at 37° C. for approximately 24 hours. This represents Production Culture #1.
[0022] 3. Transfer a portion of the hyphae colony to another SDA plate and incubate another 24 hours at 37° C. This represents Production Culture #2.
[0023] 4. Transfer a portion of the hyphae colony to another SDA plate and incubate another 24 hours at 37° C. This represents Production Culture #3. By this third culture, the hypae should be healthy and ready to be inoculated into liquid media.
[0024] 5. Prepare shaker flask(s) of sterile Sabouraud Dextrose Broth (SDB), filling them to half of their full volume.
[0025] 6. Inoculate the flask(s) containing warm (37° C.) SDB with a portion of Production Culture #3. Incubate the flask(s) at 37° C. on a rotating shaker device at approximately 150 rpm for 5 to 7 days until the culture has a confluent hyphae mat.
Protein Extraction
[0026] 1. Aseptically transfer culture fluids to the filter housing of a sterile vacuum/bottle top filter apparatus equipped with a clarifying filter. Upon applying a vacuum to the receiver bottle cap arm, hyphae remain above the filter and the fluid containing soluble extracellular proteins (filtrate) collects in the receiver bottle below. Record the filtrate volume and store at 2 to 7° C.
[0027] 2. Hyphae are aseptically transferred to a sterile pre-chilled mortar containing liquid nitrogen. This rapid freezing effectively inactivates the Pythium insidiosum culture. A sterile pestle is used to disrupt the cells and turn the mass into a powder. The powder is suspended in sterile deionized water, mixed well and incubated at 2 to 7° C. for 1 hour. The ground hyphae-in-water suspension contains both soluble intracellular proteins and insoluble hyphae fragments.
[0028] 3. The suspension is centrifuged at approximately 750×g for 1 hour, then the supernatant containing soluble intracellular proteins collected and stored at 2 to 7° C.
[0029] 4. The filtrate from Step 1 above and the supernatant from Step 3 above are combined and poured into an Erlenmeyer flask and acetone added until the suspension becomes milky-white in appearance. This suspension is placed at 2° to 7° C. until clearing occurs and the extracellular protein collects at the bottom of the flask.
[0030] 5. Carefully decant the acetone supernatant and allow the precipitate to air dry at room temperature under a fume hood for 20 minutes to vaporize all remaining acetone.
[0031] 6. Collect the precipitated protein with a volume of sterile deionized water sufficient to dissolve the precipitate and hold at 2 to 7° C. for 24 hours to dissolve soluble proteins.
[0032] 7. Centrifuge the mixture of soluble intracellular and extracellular proteins at 750×g for 30 minutes. Collect the supernatant containing only the soluble proteins and discard the precipitate containing any remaining insoluble proteins.
[0033] 8. Diafilter the supernatant under refrigeration using a sterile filter housing equipped with a 10,000 MWCO non-protein binding filter. The filtrate is discarded and the retentate stored refrigerated at 2 to 7° C. or held frozen until finished product is to be prepared.
[0034] 9. Before storing the concentrate, sample, measure and record the total combined extracellular/intracellular protein.
Preparation of Finished Product
[0035] 1. Dilute the concentrate with sterile saline to the desired protein level, then measure once more to confirm.
[0036] 2. Fill multiple or single unit dose sterile vials with finished product. A 0.2 micron filter is incorporated in-line to help assure product sterility.
[0037] 3. Apply sterile stoppers to the vials, then secure with aluminum seals.
[0038] A primary difference exists in the method of production and isolation of the present invention strain from that used in previous Mendoza et al. patents, namely, the method of production in the new product is different than that of the previous patents in the following ways:
1. The MTPI-04 strain is used rather than the MTPI-19 strain (ATCC 74446 and/or ATCC 58643); and 2. Cryogenic destruction of the hyphae is used to inactivate the Pythium culture, rather than using a chemical agent.
[0041] Preferably the immunotherapeutic concentrate contains between about 20 mcg to 5.0 mg of protein per dose. The immunotherapeutic dosage preferred for some animals is between about 20 mcg/mL and 40 mcg/mL.
[0042] The immunotherapeutic of the present invention is preferably injected intramuscularly. The vaccine can also be administered intradermally or subcutaneously by needle or needle-less methods.
[0043] A sterile carrier is used in the immunotherapeutic. The preferred carrier is water or an aqueous saline solution, particularly in humans.
[0044] The immunotherapeutic can be combined with immunizing components for other diseases to produce a multivalent vaccine.
[0045] In the following examples, the improved immunotherapeutic was prepared from P. insidiosum Strain MTPI-04 cultured, isolated, extracted and stored as previously described. It was stored at 2 to 7° C. until use.
[0046] For all Examples below the carrier was saline solution and for Examples 3-4, and 6-12 each dose was 40 mcg.
EXAMPLE 1
Human
A. Chromoblastomycosis
[0047] A 74-year-old Brazilian man had a 54-year history of a chromoblastomycosis fungal infection of his right arm. The patient had been treated several times over the years with antifungal drugs including Itraconazole, Ketoconazole and Amphotericin B without success. He entered the Institute of Dermatology (ISMD) in Belo Horizonte, Brazil because the lesions on his arm were increasing in size. Based upon the long history of unsuccessful treatments with conventional antifungal drugs, treatment began using injections of the Pythium Immunotherapeutic product derived from Strain MTPI-04 at 20 mcg/dose, injected subcutaneously, one week apart for a month. There was dramatic reduction in lesion size during the initial 7-month treatment period. Since the ISMD still found “sclerotic bodies” on some small residual lesions during the patient's last visit of Dec. 11, 2009, this suggests the infection is still present at a lower level but the treatment appears to have diminished and controlled the disease progression. Immunotherapy has begun again with the patient scheduled to visit the ISMD during February, 2010.
EXAMPLE 2
Equine
A. Sarcoids
[0048] The equine sarcoid is the most common skin tumor of horses worldwide. These locally aggressive benign tumors are widely accepted to be associated with bovine papillomavirus. Four (4) veterinarians treating a total of 6 cases of equine sarcoid disease with subcutaneous injections of the Pythium Immunotherapeutic (20 mcg/dose) reported complete resolution of sarcoid lesions in 4 cases and 50% reduction of lesions in the remaining 2 cases.
EXAMPLE 3
B. Exuberant Granulation (“Proud Flesh”)
[0049] A 30-year-old mare experienced a wound on her right rear leg over the proximal metatarsal bone that subsequently healed with excessive granulation, confirmed by histopathology. Following sharp resection of the 10 cm tumor, a series of 4 weekly intramuscular injections of the Pythium Immunotherapeutic were given. Without ancillary treatment, the lesion healed completely over a period of 5 months. The horse subsequently grew an extremely thick winter coat, something she had not done for many years.
EXAMPLE 4
C. Laminitis
[0050] A horse with a history of minor lameness due to navicular disease was also diagnosed with laminitis. The patient was given 3 weekly injections of the Pythium Immunotherapeutic. Lameness resolution was noted within 24 hours following each treatment, however lameness returned by day 6 following each treatment. An additional course of 3 weekly injections were given, this time the horse was not ridden during the treatment period. Approximately 90% clinical recovery was noted and the patient continued to improve.
EXAMPLE 5
D. Allergy
[0051] A horse with a history of atopic signs and concurrent high serum IgE antibody levels against multiple allergens was treated with a combination of Pythium Immunotherapeutic subcutaneously at 20 mcg/dose and various allergenic extract injections on days 1, 14 and 30. Serum IgE specific for the allergens used in the treatment set showed substantially reduced levels on day 30. By day 60, serum IgE was within normal limits and atopic clinical signs were resolved.
EXAMPLE 6
E. Anhidrosis
[0052] A horse with a 2-year history of clinical anhidrosis (not able to perspire) was given 3 subcutaneous injections (days 1, 7 and 21) of the Pythium Immunotherapeutic, 40 mcg/dose. Seven (7) days after the 3 rd treatment, the horse perspired normally during exercise. The attending veterinarian reports the patient continues to perspire normally during exercise at 90 days following the 3 rd injection.
EXAMPLE 7
Canine
A. Mast Cell Tumor
[0053] A 12-year-old spayed female mix breed dog had six (6) mast cell tumors (MCT's) surgically excised over a 2 year period. A new MCT measuring 4-5 cm in diameter and soft appeared on her dorsal withers and the owner refused further surgery. Subcutaneous Pythium Immunotherapy was started and one week later when presented for a 2 nd treatment, the tumor measured 2×3 cm and was hard. At 3 rd treatment, one week later, the tumor was circular, measuring 1.5 cm in diameter and 0.5 cm thick and was very hard. At 4 th treatment one week later, the tumor was 1.25 cm diameter and 0.5 cm thick and was very hard and non-painful. Administration was by subcutaneous injection. One week after the 4 th treatment, the tumor continued to shrink to 1.0 cm diameter and later disappeared. No further MCT's have recurred.
EXAMPLE 8
B. Allergy & Otitis Externa
[0054] An 8-year-old intact female Cocker Spaniel suffered with severe skin allergies most of her life. Her ears were especially nasty and were filled with purulent discharge and she had a large skin lesion on her chest that refused to heal. The dog was given weekly subcutaneous injections of the Pythium Immunotherapeutic for 4 weeks, but improvement was marked at 1 week following the initial treatment: The chest lesion was healed and the ears were clinically normal, i.e. no inflammation, no discharge and no odor. Upon 4 th injection the ears still appeared normal.
EXAMPLE 9
C. Arthritis
[0055] A 5-year-old neutered male Sheltie had congenital hip dysplasia and extreme recurrent skin allergies. He was treated with four subcutaneous weekly injections. Five (5) days following the first subcutaneous injection with the Pythium Immunotherapeutic, the dog was not itching at all and acting as if his hips were not bothering him. At the time of the last injection, the dog continued to be very active although he still was a little slow in getting up after resting. There were no apparent allergic skin problems. A year later the owner reported he was much better, with only mild allergic problems requiring antihistamines and his arthritis remains much improved.
EXAMPLE 10
D. Inflammatory Bowel Disease
[0056] A 10-year-old neutered male terrier mix with Inflammatory Bowel Disease (IBD) had continuing bouts of vomiting and diarrhea. He was treated with four subcutaneous weekly injections. The clinical signs improved markedly following the initial subcutaneous injection with the Pythium Immunotherapeutic and the dog had no more gastrointestinal episodes, was much calmer and gained 1.7 pounds at the time he was presented for a 3 rd treatment.
EXAMPLE 11
Feline
A. Asthma
[0057] A 10-year-old spayed female Siamese cat had respiratory problems consistent with feline asthma for about 2 years. She was treated with four subcutaneous weekly injections. At the time of the initial Pythium Immunotherapy injection, the cat had severe expiratory dyspnea. At second injection, the cat still had slight dyspnea but not nearly as severe. The cat was clinically normal, without dyspnea, when presented for her 3 rd injection.
EXAMPLE 12
B. Miliary dermatitis
[0058] A 10-year-old neutered male Manx cat exhibited extreme miliary dermatitis lesions. He was alopecic and had very itchy, dry, flaky skin over about 70% of his body. Subcutaneous Pythium Immunotherapy was begun. At 2 nd treatment the alopecia started to resolve and the skin was not as hot and inflamed. After a total of 8 weekly treatments, the hair had re-grown, the skin was normal and the cat was not scratching at all. There remained a small area of alopecia over the caudal ventral abdomen.
[0059] The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made, which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives. | A method and vaccine for modulating the immune system of animals with diseases other than caused by P. insidiosum, comprising administering to the animal immune modulating effective amount of the P. insidiosum, Strain MTPI-04. The vaccine uses an immune response that effectively treats and manages a variety of human and animal diseases. | 2 |
TECHNICAL FIELD
[0001] The present invention relates to a fall prevention brake buffering system for a high-speed mining elevator, in particular to a fall prevention brake buffering system suitable for a high-speed mining elevator with an elevator car guided by a flexible guide rail, which is also applicable to flexibly guided low-speed elevators and lifting systems.
BACKGROUND
[0002] The elevator car protection system widely applied presently is mainly used on elevators that employ a rigid guide rail, because the safety gear of such a safety protection system against over-speed/under-speed of the elevator car of a conventional elevator can take braking effect only on a rigid guide rail; however, when such an elevator car protection system is used on an elevator in an underground works where the geological conditions are complex and the hoistway may deform, the safety gear for fall prevention braking and protection for the elevator car may act unexpectedly; consequently, the elevator car may be stuck in the shaft, which brings a severe potential safety hazard to operation of the elevator. For elevators guided by a non-rigid guide rail, to ensure safe operation of the elevator, patent No. ZL201020286672.0 discloses an elevator car over-speed/under-speed protection system, and patent No. ZL 201120122622.3 discloses a safety gear for braking rope, which can avoid the risk of passenger injury and equipment damage in case the elevator car operates in an over-speed or under-speed state. However, some problems may occur in the fall prevention braking process owing to the high kinetic energy of a high speed elevator, for example, the braking deceleration of the elevator car is too high. Existing over-speed/under-speed protection systems for elevator cars guided by a non-rigid guide rail are only applicable in the field of low-speed elevators. There is no fall prevention brake buffering system for high-speed mining elevators yet up to now. Therefore, it is an urgent task to develop a fall prevention brake buffering system for high-speed mining elevators.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is a front view of the fall prevention brake buffering system for high-speed mining elevator according to the present invention;
[0004] FIG. 2 is a side view of the fall prevention brake buffering system for high-speed mining elevator according to the present invention;
[0005] FIG. 3 is a structural diagram of the buffer according to the present invention;
[0006] FIG. 4 is a structure diagram of the rope groove of the wedge block in the buffer according to the present invention;
[0007] FIG. 5 is a structure diagram of the tension connector in the present invention;
[0008] FIG. 6 is a structure diagram of the wedge-shaped rope clip in the tension connector according to the present invention;
[0009] FIG. 7 is a structure diagram of the braking rope tensioner according to the present invention;
[0010] FIG. 8 is a schematic diagram of the buffer according to the present invention before the buffer acts;
[0011] FIG. 9 is a schematic diagram of the buffer in the present invention after the buffer acts.
DETAILED DESCRIPTION
[0012] To overcome the drawbacks in the prior art, the present invention provides a fall prevention brake buffering system for high speed elevator, which features with compact structure, excellent buffering effect, reliable braking, and high safety.
[0013] The fall prevention brake buffering system for high-speed mining elevator according to the present invention comprises a braking rope fixed to two sides of an elevator car, one end of the braking rope is fixed to the top of a mine shaft, and the other end of the braking rope is fixed to the bottom of the mine shaft, a linkage mechanism is arranged on the bottom of the elevator car, a buffer is arranged on the top of the braking rope, a tension connector is arranged on the bottom of the braking rope, a braking rope safety gear fixed to the braking rope and connected with the linkage mechanism is arranged on the bottom of the elevator car; the buffer comprises an inverted braking rope gradual safety gear, a buffering rope connected with the braking rope is arranged in the braking rope gradual safety gear, and a buffering rope clip is arranged on the buffering rope.
[0014] The braking rope gradual safety gear comprises a gear body, a rope groove profile wedge block is arranged in the gear body, the rope groove of the rope groove profile wedge block is arranged with beryllium copper and has a bell mouth on its upper part, a lifting screw rod is arranged on the top of the rope groove profile wedge block.
[0015] The braking rope safety gear is an instantaneous braking rope safety gear, the wedge block in the instantaneous braking rope safety gear has a trumpet-shaped rope groove, and the rope groove is arranged with beryllium copper.
[0016] The tension connector comprises a wedge-shaped rope clip fastened and fixed on the braking rope by an angle steel part, a wedge block is arranged in the wedge-shaped rope clip, a fixed beam fixed by a connecting bolt is arranged below the angle steel part, and a rope clip designed to fix the terminal of the braking rope is arranged on the fixed beam.
[0017] With the technical solution described above, the fall prevention brake buffering system according to the present invention is easy to install, the buffering force of the braking rope is constant and adjustable, the fall prevention braking is reliable, and the safety of high-speed operation of an elevator guided by a non-rigid guide rail can be greatly improved. The present invention can be used as a fall prevention braking and protection system for elevator car to provide a buffering effect on the braking ropes, can achieve reliable braking against falling of the elevator, and thereby improve safety of the high-speed operation of the mining elevator. The major advantages include:
[0018] (1) The buffer on the top of the mining elevator braking rope provides a buffering effect during fall prevention braking of the elevator car; thus, the buffering of the elevator car relies on the buffer at the top of the mine shaft rather than the sliding of the elevator car on the guide rail;
[0019] (2) A gradual safety gear with a rope groove is used as the buffer for fall prevention braking of the elevator car; thus, the gradual safety gear can be utilized effectively to overcome the difficulty in buffering force setting in the fall prevention braking process of the elevator car;
[0020] (3) A tension connector that is set with maximum tension force and simple in structure is used as a tensioner on the bottom of the braking rope; thus, the tension force of the braking rope can be adjusted conveniently, and the drawback that the elevator car grabbed on the braking rope may get loose easily is overcome.
[0021] Hereunder an embodiment of the present invention will be further detailed with reference to the accompanying drawings.
[0022] As shown in FIG. 1 and FIG. 2 , the fall prevention brake buffering system for high-speed mining elevator according to the present invention mainly comprises a buffer 1 , a braking rope 2 , a braking rope safety gear 3 , a tension connector 4 , braking a rope gradual safety gear 8 , a buffering rope 9 , a buffering rope clip 10 , an linkage mechanism 11 , and an instantaneous braking rope safety gear 12 . The braking rope 2 is fixed to two sides of an elevator car 5 , one end of the braking rope 2 is fixed to the top of a mine shaft 6 , and the other end of the braking rope 2 is fixed to the bottom of the mine shaft 6 , the linkage mechanism 11 is arranged on the bottom of the elevator car 5 , the buffer 1 is arranged on the top of the braking rope 2 , the tension connector 4 is arranged on the bottom of the braking rope 2 , the braking rope safety gear 3 fixed to the braking rope 2 and connected with the linkage mechanism 11 is arranged on the bottom of the elevator car 5 , and the braking rope safety gear 3 is an instantaneous braking rope safety gear, the wedge block in the instantaneous braking rope safety gear has a trumpet-shaped rope groove, and the rope groove is arranged with beryllium copper; the buffer 1 comprises the inverted braking rope gradual safety gear 8 , the buffering rope 9 connected with the braking rope 2 is arranged in the braking rope gradual safety gear 8 , and the buffering rope clip 10 is arranged on the buffering rope 9 .
[0023] As shown in FIG. 3 and FIG. 4 , the braking rope gradual safety gear 8 in the buffer 1 mainly comprises a rope groove profile wedge block 1 - 1 , a U-shaped spring 1 - 2 , a fine adjustment screw rod 1 - 3 , a gear body 1 - 4 , a gear holder 1 - 5 , and a lifting screw rod 1 - 6 ; the gear body 1 - 4 is fitted over the braking rope 2 , the rope groove profile wedge block 1 - 1 and the gear holder 1 - 5 that are coupled with the rope groove profile wedge block 1 - 1 are arranged in the gear body 1 - 4 , the rope groove of the rope groove profile wedge block 1 - 1 is arranged with beryllium copper 1 - 7 and has a bell mouth 1 - 8 on its upper part, the U-shaped spring 1 - 2 and fine adjustment screw rod 1 - 3 are arranged on two sides of the rope groove profile wedge block 1 - 1 , and the lifting screw rod 1 - 6 is arranged on the top of the rope groove profile wedge block 1 - 1 .
[0024] As shown in FIG. 5 and FIG. 6 , the tension connector 4 comprises a wedge-shaped rope clip 4 - 1 fastened and fixed on the braking rope 2 , an angle steel part 4 - 2 fixed to the wedge-shaped rope clip 4 - 1 by bolts, and a connecting bolt 4 - 3 that is used to connect the angle steel part 4 - 2 to a fixed beam 4 - 4 that is made of channel-steel and fixed to the bottom of the shaft; the fixed beam 4 - 4 fixed by the connecting bolt 4 - 3 is arranged below the angle steel 4 - 2 , a rope clip 4 - 5 designed to fix the terminal of the braking rope 2 is arranged on the fixed beam 4 - 4 , and a wedge block 4 - 6 is arranged in the wedge-shaped rope clip 4 - 1 .
[0025] FIG. 7 is a structure diagram of the braking rope tensioner. The braking rope 2 can be tensioned up by the braking rope tensioner 7 when desired. The braking rope tensioner 7 comprises adjusting bolts 7 - 2 that are arranged in symmetry on the two sides of the braking rope 2 and mounted on the fixed beam 4 - 4 , a pressing plate 7 - 3 is fitted over the adjusting bolts 7 - 2 , and adjusting nuts 7 - 1 are arranged on the pressing plate 7 - 3 . By tightening up the adjusting nuts 7 - 1 , the pressing plate 7 - 3 will press the wedge-shaped rope clip 4 - 1 downwards, and thereby the braking rope 2 is tensioned up. When the tension force reaches a preset value, the connecting bolt 4 - 3 in the tension connector 4 is tightened up on the fixed beam 4 - 4 , and the adjusting nuts 7 - 1 , adjusting bolts 7 - 2 , and pressing plate 7 - 3 are removed; in the buffering process during fall prevention braking, the connecting bolt 4 - 3 has rated breaking strength, and the connecting bolt 4 - 3 will be broken apart when the elastic wave in the braking rope 2 is transferred to the terminal of the braking rope 2 during fall prevention braking for the elevator car 5 , and thereby the elevator car 5 is grabbed on the braking rope 2 , and would not fall slide off.
[0026] As shown in FIG. 8 and FIG. 9 , the buffer 1 according to the present invention is an inverted braking rope gradual safety gear 8 with a U-shaped spring; the buffering principle and working process of the buffer 1 is as follows:
[0027] When the elevator car 5 operates normally, the initial distance between the wedge blocks 1 - 1 is x 1 , the distance from the top of the wedge block 1 - 1 to the bottom surface of the top plate of the gear body 1 - 4 is x 2 , and the initial opening distance of the U-shaped spring 1 - 2 is x 3 . In case the elevator car 5 operates in an over-speed state, the speed limiter will stop immediately once it detects the running speed of the elevator car 5 exceeds the limit, and the linkage mechanism 11 will drive the instantaneous braking rope safety gear 12 to act, so that the elevator car 5 would be grabbed on the braking rope 2 .
[0028] As the elevator car moves downwards further, x 1 will change to x 4 and further decrease, i.e., the wedge block 1 - 1 and the braking rope 2 will be pressed towards each other, and interaction force will be created between the braking rope 2 and the wedge block 1 - 1 ; the U-shaped spring 1 - 2 suffers the reaction force of the braking rope 2 against the wedge block 1 - 1 transferred from the wedge block 1 - 1 , and its opening distance increases from the initial value x 3 to x 6 , the distance x 2 from the top of the wedge block 1 - 1 to the bottom surface of the top plate of the gear body 1 - 4 changes to x 5 and decreases gradually, till the wedge block 1 - 1 is finally pulled down to the lower end and comes into contact with the bottom surface of the gear body 1 - 4 (i.e., x 5 =0), where the opening distance x 6 of the U-shaped spring 1 - 2 doesn't increase anymore and the pressing force of the U-shaped spring 1 - 2 transferred to the wedge block 1 - 1 on the braking rope 2 keeps constant. In other words, the braking force applied by the braking rope gradual safety gear 8 on the braking rope 2 is in a steady state, and the elevator car 5 is buffered under the braking force in the fall prevention braking process; since the buffering rope 9 has to overcome the friction force continuously when it is pulled out from the braking rope gradual safety gear 8 , the kinetic energy of the elevator car 5 of the mining elevator is depleted; when the work done by the buffer 1 is equal to the kinetic energy of the mining elevator at the moment the fall prevention braking happens, the elevator car 5 of the mining elevator will enter into a still state finally; in that way, the elevator car 5 is stopped, and the purpose of effectively protecting the safety of persons, goods, and mining elevator system is attained.
[0029] Among the drawings:
1 —buffer, 2 —braking rope, 3 —braking rope safety gear, 4 —tension connector, 5 —elevator car, 6 —mine shaft, 7 —braking rope tensioner, 8 —braking rope gradual safety gear, 9 —buffer rope, 10 —buffer rope clip, 11 —linkage mechanism, 12 —instantaneous braking rope safety gear; 1 - 1 —rope groove profile wedge block, 1 - 2 —U-shaped spring, 1 - 3 —fine adjustment screw rod, 1 - 4 —gear body, 1 - 5 —gear holder, 1 - 6 —lifting screw rod, 1 - 7 —beryllium copper, 1 - 8 —bell mouth; 4 - 1 —wedge-shaped rope clip, 4 - 2 —angle steel part, 4 - 3 —connecting bolt, 4 - 4 —fixed beam, 4 - 5 —rope clip, 4 - 6 —wedge block; 7 - 1 —adjusting nut, 7 - 2 —adjusting bolt, 7 - 3 —pressing plate. | Disclosed is a fall prevention brake buffering system for high-speed mine lift, including brake ropes ( 2 ) fixed on two sides of a car ( 5 ). One end of the brake rope ( 2 ) is fixed on the top part of a vertical well ( 6 ), and the other end is fixed on the bottom part of the vertical well ( 6 ). A linkage mechanism ( 11 ) is arranged at the bottom of the car ( 5 ). A buffer ( 1 ) is arranged at the top of the brake rope ( 2 ), and a tension connector ( 4 ) is arranged at the bottom of the brake rope ( 2 ). A brake rope safety tong ( 3 ) fixed on the brake rope ( 2 ) and connected with the linkage mechanism ( 11 ) is arranged at the bottom of the car ( 5 ). The buffer ( 1 ) includes an inverted brake rope gradual safety tong ( 8 ) with a buffering rope ( 9 ) provided therein and connected with the brake rope ( 2 ). A buffering rope clip ( 10 ) is arranged on the buffering rope ( 9 ). The system is convenient to install, and the buffering force of the brake rope is constant and adjustable. The system realizes reliable fall prevention brake function, greatly improves safety performance during high-speed operation of a lift with non-rigid rails, and increases safety performance during high-speed operation of a mine lift. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. application Ser. No. 14/350,138, filed Mar. 19, 2009, currently allowed, which claims the benefit of International Application Number PCT/IB2012/055900, filed 26 Oct. 2012, which claims the benefit of Application Number EP11187025.9, filed 28 Oct. 2011. The entire contents of each of the aforesaid applications are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to an improved process for preparing (2R,3aR,10Z,11aS, 12aR,14aR)-cyclopenta[c]cyclopropa[g][1,6]diazacyclotetradecine-12a(1H)-carboxylic acid, 2,3,3a,4,5,6,7,8,9,11a,12,13,14,14a-tetradecahydro-2-[[7-methoxy-8-methyl-2-[4-(1-methylethyl)-2-thiazolyl]-4-quinolinyl]oxy]-5-methyl-4,14-dioxo-, ethyl ester (or compound (2) as referred to hereinafter). This compound is an intermediate in the overall synthesis route of the macrocyclic compound TMC 435. TMC 435 is an inhibitor of NS3/4A protease which plays an important role in the replication of the hepatitis C virus.
BACKGROUND OF THE INVENTION
[0003] The hepatitis C virus (HCV) is the leading cause of chronic hepatitis, which can progress to liver fibrosis leading to cirrhosis, end stage liver disease, and HCC (hepatocellular carcinoma), making it the leading cause of liver transplantations. Anti-HCV therapy, based on (pegylated) interferon-alpha (IFN-α) in combination with ribavirin, suffers from limited efficacy, significant side effects, and is poorly tolerated in many patients. This prompted the search for more effective, convenient and better-tolerated therapy. Recently, certain protease inhibitors have been approved for use in combination with peginterferon plus ribavirin. However, there is a need for improved protease inhibitors.
[0004] WO-2007/014926 describes macrocyclic cyclopentane and proline derivatives including the compound TMC-435 with the structure represented hereafter.
[0000]
[0005] TMC-435 is a very effective inhibitor of the HCV NS3 protease and is particularly attractive in terms of pharmacokinetics. Due to its favorable properties it is being developed as an anti-HCV drug. Consequently there is a need for producing larger quantities of this active ingredient based on processes that provide the product in high yield and with a high degree of purity.
[0006] Synthesis procedures to prepare TMC-435 have been disclosed in WO-2007/014926 wherein TMC-435 is identified as compound (47) in Example 5 on page 76.
[0007] An important step in the synthesis of TMC-435 as described in WO-2007/014926 is the ring-closing metathesis (RCM) which is depicted below:
[0000]
[0008] Said ring-closing metathesis has been described in WO-2007/014926 in Example 4 Step E on page 74. Ring-closing metathesis of intermediate (44) in WO-2007/014926 is done by means of a Hoveyda-Grubbs first-generation catalyst in 1,2-dichloroethane at 75° C. for 12 hours resulting in intermediate (45) with a 60% yield. Large amounts of oligomeric byproducts are formed under these conditions, and tedious purification procedures, e.g. preparative chromatography, are required to isolate the product from the reaction mixture.
[0009] The efficiency by which the ring-closing metathesis cyclization occurs is important because the starting material, i.e. compound (1) or intermediate (44) in WO-2007/014926, is the result of a long multi-step process. The ring-closing metathesis reaction produces side products such as dimers and polymers thereby lowering the yield and complicating product isolation. One solution that has been proposed in Goldring et al., Tetrahedron Letters 39, 4955-4958 (1998), is the introduction of a N-protective group, in particular a Boc group, on the secondary amide function which is removed after the ring-closing metathesis. Said introduction and removal of a N-protective group to increase the yield of ring-closing metathesis in the synthesis of macrocyclic compounds has also been described in WO-2007/030656, WO-2009/073780 and WO-2010/015545. The N-protective group described in said references is e.g. C 1-6 alkyloxycarbonyl such as Boc (tert-butyloxycarbonyl), C 1-6 alkylcarbonyl, benzoyl and arylcarbonyl (in particular, the N-protective group is benzoyl).
[0010] When applying this N-protective group technology using Boc in the ring-closing metathesis of compound (1) it turned out that the Boc-group could only be removed from the macrocyclic metathesis product under drastic conditions, in particular prolongued heating with strong acids (e.g. sulfuric acid or benzenesulfonic acid), resulting in product decomposition during the Boc-deprotection process. This procedure is depicted below in Scheme 1.
[0000]
[0011] When applying the N-benzoyl protective group, on the other hand, cleavage of the benzoyl protecting group can be done by treatment of the N-benzoylated macrocycle with bases such as KOH. This cleavage is also accompanied by product loss due to non-selective attack of the base and ring opening of the macrocyle. Introduction of both the Boc and the benzoyl group needs an additional synthesis step, and a purification is necessary before the ring closing metathesis to avoid catalyst poisoning.
[0012] Hence there is a need to improve the efficiency of this ring closing metathesis reaction, preferably with as few additional steps as possible. In particular there is a need for a protecting group on the secondary amide function that can be removed easily under non-drastic reaction conditions.
[0013] It now has been found that halogenated acyl groups can be used in situ in the ring-closing metathesis reaction and can be removed easily upon completion of the reaction. It further has been found that the protection-macrocyclization-deprotection cycle can be conducted in a one-pot process in high yield of the end product, which is obtained in high purity.
[0014] The process of the invention offers a straightforward, quick and economic procedure to produce compound (2), which can easily converted to the end product TMC-435.
DESCRIPTION OF THE INVENTION
[0015] In one aspect, the present invention relates to a process for preparing a compound of formula (II), which is characterized by the steps of
a) acylating a diene compound of formula (I), wherein R 1 is C 1-6 alkyl,
[0000]
with a halogenated acyl compound (R 2 —CO) 2 O or R 2 —COCl, wherein R 2 is polyhaloC 1-4 alkyl, followed by a ring-closing metathesis reaction of the acylated reaction product with a suitable catalyst in a reaction-inert solvent to yield a compound of formula (III); and
[0000]
b) removing the halogenated acyl group from compound (III) thus obtaining the compound of formula (II) wherein R 1 is C 1-6 alkyl.
[0000]
[0018] As used in the foregoing definitions:
halo is generic to fluoro, chloro, bromo and iodo; C 1-4 alkyl defines straight and branched chain saturated hydrocarbon radicals having from 1 to 4 carbon atoms such as, for example, methyl, ethyl, propyl, butyl, 1-methylethyl, 2-methylpropyl and the like; C 1-6 alkyl is meant to include C 1-4 alkyl and the higher homologues thereof having 5 or 6 carbon atoms, such as, for example, 2-methylbutyl, pentyl, hexyl and the like;
polyhaloC 1-4 alkyl is defined as polyhalosubstituted C 1-4 alkyl, in particular C 1-4 alkyl (as hereinabove defined) substituted with 1 to 6 (e.g. 1 to 4) halogen atoms such as fluoromethyl, difluoromethyl, trifluoromethyl, chloro-difluoromethyl, trifluoroethyl, heptafluoro-propyl and the like. Preferably, such polyhaloC 1-4 alkyl groups are entirely substituted by halo atoms (i.e. there are no hydrogen atoms).
[0022] In an embodiment of the present invention the substituent the substituent R 1 in the compounds of formula (II) is defined C 1-4 alkyl, in particular ethyl, and R 2 in the halogenated acyl compound (R 2 —CO) 2 O or R 2 —COCl represents polyhaloC 1-4 alkyl in particular trifluoromethyl, chlorodifluoromethyl, heptafluoropropyl, and the like.
[0023] It is believed that the acylation reaction performed on compound of formula (I) yields an N-acylated reaction product but it is not excluded that also O-acylation occurs. Likewise, the acyl group in compounds of formula (III) can be attached to the N or to the O atom of the amide functional group.
[0024] The ring-closing metathesis in reaction step a) above to obtain compound (III) is done by an olefin ring-closing metathesis reaction in the presence of a suitable metal catalyst such as e.g. an ylidene Ru-based catalyst, in particular an optionally substituted alkylidene or indenylidene catalyst, such as [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(phenylmethylene)(tricyclohexylphosphine)ruthenium, (Grubbs 2 catalyst), [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[2-(1-methylethoxy-κO)phenyl]methylene-κC]ruthenium (Hoveyda-Grubbs 2 catalyst) dichloro(3-phenyl-1H-inden-1-ylidene)bis(tricyclohexylphosphine)ruthenium or bis(tricyclohexyl-phosphine) [(phenylthio)methylene]ruthenium dichloride. Other catalysts that can be used are Grubbs first and Hoveyda-Grubbs first generation catalysts, i.e. dichloro(phenylmethylene)bis(tricyclohexylphosphine)ruthenium and dichloro[[2-(1-methylethoxy-α-O)phenyl]methylene-α-C](tricyclohexylphosphine)ruthenium, respectively. Of particular interest are the catalysts[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene) (tricyclohexylphosphine)ruthenium (M2 catalyst), [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(triphenylphosphine) ruthenium (M20 catalyst) and [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[4-[(dimethylamino)sulfonyl]-2-(1-methylethoxy-κO)phenyl]methyl-κC]ruthenium (Zhan1b catalyst).
[0025] The metathesis reactions can be conducted in a suitable solvent such as for example an ether, e.g. THF, dioxane; halogenated hydrocarbons, e.g. dichoromethane, chloroform, 1,2 dichloroethane and the like, aromatic hydrocarbons, e.g. toluene, or halogenated aromatic hydrocarbons like trifluoromethylbenzene, fluorobenzene, hexafluorobenzene and the like.
[0026] The protection step a) whereby the secondary amide function is protected with a R 2 —CO group by acylating a compound of formula (I) with a halogenated acyl compound (R 2 —CO) 2 O or R 2 —COCl can be performed using any of the conventional nitrogen-protection protocols and conditions well known in the art. Suitable protection procedures may also be found in the Working Examples section herein.
[0027] Removing the halogenated acyl group R 2 —CO from compound (III) in step b) by deprotection can be performed using any of the conventional nitrogen-deprotection protocols and conditions well known in the art. Suitable deprotection procedures may also be found in the Working Examples section herein, for instance treatment with a secondary amine, e.g. an aqueous dimethylamine solution.
[0028] In an embodiment of the present invention, steps a) and b) are executed as a “one pot synthesis” procedure.
[0029] The intermediate products that are prepared by the process of the invention need not be isolated (e.g. from the reaction mixture including solvent) or purified, and hence this may reduce the number of process steps that need to be taken. For example the product of process step (a) (the compound of formula (III)) need not be isolated but may be used directly in the subsequent step (b) (where the halogenated acyl group is removed to yield a compound of formula (II)). Similarly, the acylation and metathesis reaction steps may be performed with the need to isolate any intermediate products.
[0030] In a further aspect of the invention it has been found that the addition of a reaction solvent soluble tetraalkylammonium iodides such as e.g. tetramethylammonium iodide (TMAI), tetraethylammonium iodide (TEAI), tetrapropylammonium iodide (TPAI) or tetrabutylammonium iodide (TBAI), improves the reaction rate and yield of the ring closing metathesis reaction that is carried out in the presence of a ylidene Ru based catalyst (see Examples 10 to 13). The tetraalkylammonium iodides have to be soluble in the solvent chosen for conducting the ring closing metathesis and for instance in apolar solvents the lower alkyl tetraalkylammonium iodides such as TMAI may not be dissolve completely and a higher alkyl tetraalkylammonium iodides should then be used such as e.g. TBAI.
[0031] The present invention also relates to novel compounds of formula (III)
[0000]
[0000] wherein R 1 represents C 1-6 alkyl and R 2 represents polyhaloC 1-4 alkyl.
[0032] A particular group of compounds of formula (III) are those compounds of formula (III) wherein R 1 represents ethyl and R 2 represents trifluoromethyl, chlorodifluoromethyl, or heptafluoropropyl.
[0033] In an embodiment of the present invention the substituent R 1 in the compounds of formula (III) are defined as R 1 represents C 1-4 alkyl, in particular ethyl.
[0034] In a further embodiment, there is provided a step for the conversion of the compound of formula (II) (or other compound that results from the process of the invention) to the final HCV protease inhibitor (e.g. TMC435), which process may involve conversion of the —C(O)OR 1 moiety to —C(O)—N(H)SO 2 -cyclopropyl in accordance with known methods (e.g. by reaction with sulfonamine) The final protease inhibitor may then be converted into a pharmaceutical product in a further process step, for example by contacting the product with a pharmaceutically acceptable carrier, diluent and/or excipient. Hence there is provided a corresponding process for preparing such a medicament (or pharmaceutical composition/formulation).
[0035] Although it is preferred that the process of the invention may be carried out on precursors to the HCV protease inhibitor TMC435, it will be understood that this methodology may be used to synthesise any macrocycle where a metathesis reaction is the key step. This is embraced in the invention. For example, particularly, the methodology may be used to synthesise other (e.g. similar) HCV protease inhibitors.
[0036] In this respect, there is provided a process as described herein, but wherein the following compounds are prepared:
[0000]
[0000] wherein:
n is 0-8 (e.g. 0-6);
R x represents hydrogen;
G represents —OR x1 or —N(H)SO 2 R x2 ;
R x1 represents hydrogen or C 1-6 alkyl;
R x2 represents C 1-6 alkyl or C 3-6 cycloalkyl;
X represents N or CH;
Y represents N or CH;
when Y represents N, then Y 1 represents hydrogen or C 1-6 alkyl;
when Y represents CH, then Y 1 represents —C(O)—R x3 , —S(O) 1-2 —R x3 , —C(S)—R x3 , —N(R x3 )—R x4 , —N(H)—C(O)—O—R x3 or —N(H)—C(O)—R x4 ;
R x3 and R x4 independently represent C 1-6 alkyl, C 3-6 cycloalkyl, aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from halo and C 1-6 alkyl);
more preferably, R x3 represents C 1-6 alkyl or C 3-6 cycloalkyl (e.g. tert-butyl);
more preferably, R x4 represents aryl or heteroaryl, e.g. heteroaryl (e.g. a 5- or 6-membered heteroaryl group containing one to four, e.g. one or two heteroatoms, so forming e.g. pyrimidine (which latter artl/heteroaryl groups are optionally substituted by one or more substituents selected from halo and C 1-6 alkyl, e.g. methyl);
L represents —O— or —O—C(O)—;
R y represents aryl, heteroaryl or cyclic non-aromatic group, all of which are optionally substituted by one or more substituents selected from halo, C 1-6 alkyl or R 4 , R 5 and R 6 (as defined below);
for example R y may represent the following groups:
[0000]
[0000] which R y groups may be substituted as defined herein, e.g. by halo (e.g. fluoro).
[0037] Hence, the R x moiety may be converted from H to —C(O)R 2 (as herein defined), followed by metathesis and removal of the —C(O)R 2 moiety.
[0038] Most preferably, in the above formulae:
[0000] R y represents:
[0000]
[0000] in which:
R 4 is selected from the group consisting of phenyl, pyridin-4-yl,
[0000]
wherein R 4a is, each independently, hydrogen, halo, C 1-6 alkyl, amino, or mono- or di-C 1-6 alkylamino;
R 5 represents halo, C 1-6 alkyl, hydroxy, C 1-6 alkoxy or polyhaloC 1-6 alkyl (e.g. is methyl, ethyl, isopropyl, tert-butyl, fluoro, chloro, or bromo);
R 6 represents C 1-6 alkoxy, mono- or diC 1-6 alkylamino (in particular, R 6 represents methoxy);
in particular, R y represents:
[0000]
[0000] in which the squiggly line on the quinolinyl group represents the point of attachment to the O atoms of the macrocycle (and the precursor thereto).
EXPERIMENTAL PART
[0043]
[0044] The following reactions (Examples 1-7) were performed in the presence of 5,12-naphthoquinone (NQ), which was used as an internal standard (IS) to determine in situ yields by HPLC analysis. Solutions of the NQ in dichloromethane or in toluene were prepared by mixing 0.206 g of NQ with 100 mL of dichloromethane, or 0.73 g of NQ with 150 mL of toluene, respectively, for 5 minutes, then, optionally, filtering the resulting mixtures. Aliquots of the mixtures of the NQ in dichloromethane or toluene were used in the reactions.
[0045] All quantitative analyses described in the experimental part were performed using standard HPLC techniques and using reference materials.
[0046] The following analytical method can be used to monitor the reactions described in the working examples below.
[0000]
UPLC System
Parameters
Column:
Acquity UPLC BEH C18 2.1 × 50 mm 1.7 μm
Column Temperature:
35° C.
Autosampler
Room temperature
Temperature:
Flow rate:
0.6 ml/min
Wash solvents:
Weak: water-methanol (90/10, v/v): 600 μl
Strong: methanol-water (90/10, v/v): 200 μl
Injection volume:
2.5 μl - Partial loop with needle overfill
Detection wavelength:
UV 240 nm
Dilution solvent:
DMF
Mobile phase A:
10 mM NH 4 OAc in water/acetonitrile (95/5; v/v)
Mobile phase B:
Acetonitrile
Time
Gradient
(min)
% A
% B
0
20
80
2
0
100
2.5
0
100
2.6
20
80
3
20
80
Example 1
Path “a”
[0047] 1 mL of a solution of NQ in dichloromethane (as prepared above) was added to a solution of 0.17 g (0.24 mmol) of compound (1) in 6 mL of dichloromethane and the resulting solution refluxed with magnetic stirring in a Radley's Caroussel tube for 1 hour. The solution was cooled and a t 0 sample was taken to determine initial ratio internal standard (IS) over compound (1). 0.5 mL of a solution of 0.008 g of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium (M2 catalyst) in 1 mL of dichloromethane was added and the resulting solution heated to reflux. A sample taken after 3 hours contains 64.8% of unconverted compound (1), 6.5% of the desired compound (2), and 14% of oligomeric species (HPLC area %). After 20 hours reflux, the analysis showed 59% of unconverted compound (1) with 11% of the desired compound (2) formed together with 28% of oligomeric species.
Example 2
Path “b” Wherein R 2 is CF 3
[0048] 1 mL of a solution of NQ in dichloromethane (as prepared above) was added to a solution of 0.17 g (0.24 mmol) of compound (1) in 6 mL of dichloromethane and the resulting solution refluxed with magnetic stirring in a Radley's Caroussel tube for 1 hour. The solution was cooled and a sample was taken to determine initial ratio IS over compound (1). 0.5 mL of trifluoroacetic anhydride (CF 3 CO) 2 O was added, and the mixture refluxed for 35 minutes. 0.5 mL of a solution of 0.008 g of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine) ruthenium (M2 catalyst) in 1 mL of dichloromethane was added and the resulting solution heated to reflux. A sample taken after 3 hours contained 4% of unconverted compound (1), 69% of the desired monomeric macrocycle compound (III-a), wherein R 2 is CF 3 , and 0.8% of “acetylated compound (1)” (HPLC area %). The in situ yield of compound (III-a), wherein R 2 is CF 3 , determined based on the IS, was 65%.
[0000]
Example 3
Path “b” Wherein R 2 is CClF 2
[0049] 3.5 mL of a solution of NQ in dichloromethane (as prepared above) and 0.17 mL (1 mmol) of chlorodifluoroacetic anhydride was added to a 0.1192 M solution of compound (1) (2.5 mL, 0.298 mmol) in dichloromethane and the resulting solution refluxed with magnetic stirring in a Radley's Caroussel tube for 1 hour 20 minutes. The solution was cooled and a t 0 sample was taken.
[0050] 0.2 mL of a solution of 0.018 g of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexyl-phosphine)-ruthenium (M2 catalyst) in 1 mL of dichloromethane was added and the resulting solution heated to reflux. A sample taken after 40 minutes contained 78% of the desired monomeric macrocycle compound (III-a), wherein R 2 is CClF 2 , and no detectable amounts of compound (1) and “acylated compound (1)” (HPLC area %). The in situ yield of compound (III-a), wherein R 2 is CClF 2 , determined based on the IS, was 95%.
[0000]
Example 4
Path “b” Wherein R 2 is CF 3
[0051] A solution of NQ in dichloromethane (3.5 mL) (as prepared above) and trifluoroacetic anhydride (0.14 mL, 1 mmol) was added to a 0.1192 M solution of compound (1) (2.5 mL, 0.298 mmol) in dichloromethane and the resulting solution refluxed with magnetic stirring in a Radley's Caroussel tube for 1 hour 20 minutes. The solution was cooled and a t0 sample was taken. 0.2 mL of a solution of 0.018 g of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium (M2 catalyst) in 1 mL of dichloromethane was added and the resulting solution heated to reflux. A sample taken after 40 minutes contained 77% of the desired compound (III-a), wherein R 2 is CF 3 , 2.4% of unreacted compound (1) and 0.5% of “acylated compound (1)” (HPLC area %). The in situ yield of compound (III-a), wherein R 2 is CF 3 , determined based on the IS, was 94%.
[0000]
Example 5a
Path “b” Wherein R 2 is CF 3
[0052] A 1000 mL round bottom flask, equipped with mechanical stirring, thermometer, distillation/reflux insert and nitrogen inlet, is charged with 130 mL of a 6.6 weight % solution of compound (1) in DCM (15.5 mmol). Separately, in a 1000 mL beaker, 0.2 g NQ was stirred with 450 mL of toluene for 10 minutes, the mixture filtered to give a clear yellow solution which was added to the flask. The yellow reaction mixture in the flask was stirred and heated and a solvent mixture was distilled off until the internal temperature reached 90° C. (95 mL of distillate was condensed). The mixture was cooled to 50° C. and 6.9 mL (50 mmol) of trifluoroacetic anhydride was added. The resulting solution was refluxed with stirring for 1 hour. The mixture was cooled to 40° C., 0.15 g of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium (M2 catalyst) was added and the resulting purple-red solution heated to 60° C. for 1 hour and 10 minutes. A sample taken after 30 minutes showed almost complete conversion of the dienes: 2.1% of unreacted compound (1), 25.7% of the desired monomeric macrocycle compound (III-a), wherein R 2 is CF 3 , and 0.7% of “acylated compound (1)”, and 4.3% of oligomeric species (HPLC area %, the rest IS and toluene). The in situ yield of the desired monomeric macrocycle compound (III-a), wherein R 2 is CF 3 , determined based on the IS, was 67%.
[0000]
Example 5b
Path “b” Wherein R 2 is CF 2 CF 2 CF 3
[0053] 3.5 mL of a solution of NQ in DCM (prepared as above) and 0.24 mL (1 mmol) of perfluorobutyric anhydride was added to a 0.1192 M solution of compound (1) (2.5 mL, 0.298 mmol) in DCM and the resulting solution refluxed with magnetic stirring in a Radley's Caroussel tube for 1 hour 20 minutes. 0.2 mL of a solution of 0.018 g of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium (M2 catalyst) in 1 mL of DCM was added and the resulting solution heated to reflux. A sample taken after 40 minutes showed the presence of 73% of the desired monomeric macrocycle T3009-COCF 2 CF 2 CF 3 , 4% of T3008-COCF 2 CF 2 CF 3 , and 3% of oligomeric species (HPLC-MS, UV detection area %). The in situ yield of T3009-COCF 2 CF 2 CF 3 , determined based on the IS, was 73%.
[0054] The reaction mixture was refluxed for 3 hours 20 minutes (total cyclization reaction time 4 hours), then cooled to room temperature, 0.5 mL of ethanolamine was added and stirred for 1 hour. A sample analyzed by LC-MS showed the formation of a 2:1 mixture of the undesired macrocycle cleavage product, and the desired product.
[0000]
Example 6
[0055] The reaction mixture of Example 4 was allowed to cool to 30° C., and 0.24 g of 2-mercaptonicotinic acid (MNA) was added, followed by the addition of 25 mL of 1-butanol, and 0.2 mL of triethylamine Analysis of this mixture after 10 minutes showed no detectable amounts of compound (2). Further 13.5 mL of triethylamine was added, and the mixture stirred overnight. Analysis of this reaction mixture showed a 12:15 mixture of the desired compound (2) and monomeric macrocycle compound (III-a), wherein R 2 is CF 3 . The mixture was then evaporated to an oil, which was dissolved in 150 mL DCM and stirred intensively with 100 mL of water and 2.3 mL of a 40% aqueous solution of dimethylamine for 2 hours. The layers were separated, the organic layer diluted with 250 mL DCM and stirred with 6 g charcoal at room temperature for 2 hours. The mixture was filtered and evaporated to dryness to give 6.7 g of compound (2) (64% physical yield).
[0000]
Examples 7, 8 and 9
The Use of (2-Methylamino)Ethanol (N-Methylethanolamine) for Acyl Cleavage Vs. The Use of Dimethylamine
[0056] The starting material, compound (III-a) wherein R 2 is CClF 2 , for this experiment was prepared according to Example 3.
[0057] An amount of 5 g of starting material was distributed over three 15 ml test-tubes. To the first one, 6 equivalents of dimethylamine were added. This corresponded to 345 μL of the 40 wt % aqueous solution of dimethylamine. The resulting (biphasic) solution was stirred vigorously at room temperature.
[0058] To both the other two test-tubes, 5 equivalents N-methyl ethanolamine (corresponding to 182 μL) were added and one of the resulting solutions was stirred vigorously at room temperature and the other one was heated to 40° C. in an easy-max.
[0059] The reactions were monitored regularly by LC-analysis over time.
[0000]
[0000]
TABLE 1
conversion of starting material (%) over time
Conversion of starting material (%)
Example 7
Example 8
Example 9
Time
6 equivalents
5 eq. N-methyl
5 eq. N-methyl
(minutes)
dimethylamine
ethanolamine
ethanolamine at 40° C.
15
97.5
97.8
87.3
30
100
100
96.2
Example 10
Reaction of Diethyldiallylmalonate: Ring Closing Metathesis Reaction Rate Improvement by a Addition of an Iodide Compound i.e. Tetrabutyl-Ammoniumiodide
[0060] In an NMR-tube, a 0.2 M solution of 700 μL CD 2 Cl 2 and 34 μL diethyldiallylmalonate (DEDAM) (0.994 g/ml) was made. Stock solutions of M2 catalyst in DCM (665 mg in 10 ml) and tetrabutylammonium iodide (TBAI) (518 mg in 10 ml) were made and 20 μL of each stock solution (containing 1 mol % M2 and 2 mol % TBAI respectively) were added to the NMR tube.
[0061] Another reaction mixture was prepared in parallel and analogous to the one above, but instead of adding 20 μL of the TBAI stock solution, 20 μL of pure DCM was added. Both NRM tubes were left unstirred at room temperature and analyzed by NMR at certain points over a period of 24 hours. Conversions were calculated by means of the appearance and disappearance of the vinylic protons vs. the protons of the ethyl-group of the ester function and are represented vs time in the FIG. 1 . From FIG. 1 it can be seen that the reaction rate and yield for the conversion of diethyldiallylmalonate (DEDAM) by the M2 catalyst is improved in the presence of the iodine compound tetrabutylammonium iodide (TBAI).
Example 11a
Reaction of Compound (1) with (ClCF 2 CO) 2 O and M2 (Path “b”), 50 L/M Dilution, Batch, No Iodide Compound
[0062] An EasyMax reactor was charged with 7 mL of a solution of compound (1) (1.99 mmol) and chlorodifluoroacetic anhydride (4 mmol) in DCM. 95.6 mL of DCM was added and the resulting yellow solution refluxed with stirring for 1 h 30 min. 2.22 mL of a DCM solution containing 28.39 mg (0.03 mmol) of [1,3-bis(2,4,6-trimethyl-phenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium (M2 catalyst) was added and the resulting red-brown solution heated to reflux for 4 hours. After cooling to room temperature, the reaction mixture was treated with a solution of 2-mercaptonicotinic acid (46.36 mg, 0.3 mmol) in 40% aqueous dimethylamine solution (1.26 mL, 9.96 mmol) and 5 mL water, and stirred at room temperature for 1 hour. The phases were separated, the organic phase was treated with 30 mL of DMF and was evaporated in vacuo at 60 deg C to give a DMF solution of the desired deacylated macrocycle compound (2) which was analyzed by quantitative HPLC. Yield: 79.9%.
Example 11b
Reaction of Compound (1) with (ClCF 2 CO) 2 O and M2 (Path “b”), 50 L/M Dilution, Batch, 10 Equivalents TEAI
[0063] An EasyMax reactor was charged with tetraethylammonium iodide (TEAI) (76.83 mg, 0.30 mmol), and 7 mL of a solution of compound (1) (1.99 mmol) and chlorodifluoroacetic anhydride (4 mmol) in DCM. 95.6 mL of DCM was added and the resulting brown solution refluxed with stirring for 1 hour 30 minutes. 2.22 mL of a DCM solution containing 28.39 mg (0.03 mmol) of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)-ruthenium (M2 catalyst) was added and the resulting red-brown solution heated to reflux for 4 hours. Work up was done as above. Yield: 80.2%.
[0000]
TABLE 2
yield comparison of Examples 11a and 11b
Example:
11a
11b
iodide compound:
no
10 eq. TEAI
yield of compound (2)
79.9%
80.2%
Example 12a
Reaction of Compound (1) with 1.2 Equivalent (ClCF 2 CO) 2 O and M2 (Path “b”), 20 L/M Dilution, No Iodide Compound
[0064] An EasyMax reactor was charged with 85 mL DCM and heated to reflux with stirring. 5 mL of a DCM solution containing 71.26 mg (0.08 mmol) of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium (M2 catalyst) was added. Next, of 15.1 mL of DCM solution containing 3.51 g (5 mmoles) of compound (1) and 1.05 mL (6 mmoles) of chlorodifluoroacetic anhydride was added and the mixture was stirred at reflux for 13 hours. After cooling to room temperature, the reaction mixture was treated with a solution of 2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylamine solution (3.17 mL) and 5 mL water, and stirred at room temperature for 1 hour. The phases were separated, and the organic phase was submitted to quantitative HPLC analysis. Yield: 76.3%.
Example 12b
Reaction of Compound (1) with 1.2 Equivalent (ClCF 2 CO) 2 O and M2 (Path “b”), 20 L/M Dilution, 0.1 Eq. KI
[0065] An EasyMax reactor was charged with 85 mL DCM and heated to reflux with stirring. 83.0 mg of potassium iodide were added and the mixture stirred for 5 minutes. 5 mL of a DCM solution containing 71.26 mg (0.08 mmol) of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium (M2 catalyst) was added. Next, of 14.53 mL of DCM solution containing 3.51 g (5 mmoles) of compound (1) and 1.05 mL (6 mmoles) of chlorodifluoroacetic anhydride was added via a syringe pump over 6 hours. After termination of the addition, the mixture was further stirred at reflux for 3.5 hours. After cooling to room temperature, the reaction mixture was treated with a solution of 2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylamine solution (3.17 mL) and 5 mL water, and stirred at room temperature for 1 hour. The phases were separated, and the organic phase was submitted to quantitative HPLC analysis. Yield: 86.6%.
[0000]
TABLE 3
yield comparison of Examples 12a and 12b
Example:
12a
12b
iodide compound:
no
0.1 eq. KI
yield of compound (2)
76.3%
86.6%
Example 13a
Reaction of Compound (1) with 1.2 Equivalent (ClCF 2 CO) 2 O and M2 (Path “b”), 20 L/M Dilution, No Iodide Compound
[0066] A catalyst stock solution was prepared by dissolving 113 mg of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium (M2 catalyst) in 8 mL DCM at room temperature. An EasyMax reactor was charged with 85 mL DCM and heated to reflux with stirring. 1.67 mL of the above catalyst stock solution was added to the reactor and the mixture stirred at reflux for 5 minutes. Using two separate syringe pumps, addition of the two solutions was started at the same time: 3.33 mL of the above catalyst stock solution were added over 6 hours 15 minutes and 13.87 mL of a DCM solution containing 3.51 g (5 mmoles) of compound (1) and 1.05 mL (6 mmoles) of chlorodifluoroacetic anhydride were added over 6 hours. After termination of the addition, the mixture was further stirred at reflux for 3.5 hours. After cooling to room temperature, the reaction mixture was treated with a solution of 2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylamine solution (3.17 mL) and 5 mL water, and stirred at room temperature for 1 hour. The phases were separated, and the organic phase was submitted to quantitative HPLC analysis. Yield: 80.6%.
Example 13b
Reaction of Compound (1) with 1.2 Equivalent (ClCF 2 CO) 2 O and M2 (Path “b”), 20 L/M Dilution, 0.1 Equivalent TBAI
[0067] A catalyst stock solution was prepared by dissolving 114 mg of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium (M2 catalyst) and 297 mg tetrabutylammonium iodide in 8 mL DCM at room temperature.
[0068] An EasyMax reactor was charged with 85 mL DCM and heated to reflux with stirring. 1.67 mL of the above catalyst stock solution was added to the reactor and the mixture stirred at reflux for 5 minutes. Using two separate syringe pumps, addition of the two solutions was started at the same time: 3.33 mL of the above catalyst stock solution were added over 6 hours 15 minutes and 13.87 mL of a DCM solution containing 3.51 g (5 mmoles) of compound (1) and 1.05 mL (6 mmoles) of chlorodifluoroacetic anhydride were added over 6 hours. After termination of the addition, the mixture was further stirred at reflux for 3.5 hours. After cooling to room temperature, the reaction mixture was treated with a solution of 2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylamine solution (3.17 mL) and 5 mL water, and stirred at room temperature for 1 hour. The phases were separated, and the organic phase was submitted to quantitative HPLC analysis. Yield: 86.4%.
Example 13c
Reaction of Compound (1) with 1.2 Equivalent (ClCF 2 CO) 2 O and M2 (Path “b”), 20 L/M Dilution, 0.1 Eq. TEAI
[0069] A catalyst stock solution was prepared by mixing 124 mg of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium (M2 catalyst) and 173 mg tetraethylammonium iodide in 6.7 mL DCM at room temperature The tetraethylammonium iodide did not completely dissolve—the supernatant, i.e. the solution phase of this mixture was used. An EasyMax reactor was charged with 85 mL DCM and heated to reflux with stirring. 1.67 mL of the above catalyst stock solution was added to the reactor and the mixture stirred at reflux for 5 minutes. Using two separate syringe pumps, addition of the two solutions was started at the same time: 3.33 mL of the above catalyst stock solution were added over 3 hours 15 minutes and 13.87 mL of a DCM solution containing 3.51 g (5 mmoles) of compound (1) and 1.05 mL (6 mmoles) of chlorodifluoroacetic anhydride were added over 3 hours. After termination of the addition, the mixture was further stirred at reflux for 3 hours. After cooling to room temperature, the reaction mixture was treated with a solution of 2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylamine solution (3.17 mL) and 5 mL water, and stirred at room temperature for 1 hour. The phases were separated, and the organic phase was submitted to quantitative HPLC analysis. Yield: 89.3%.
[0000]
TABLE 4
yield comparison of Examples 13a to 13c
Example:
13a
13b
13c
iodide compound:
no
0.1 eq. TBAI
0.1 eq. TEAI
yield of compound (2)
80.6%
86.4%
89.3%
Example 14
Reaction of Compound (1) with 2.0 Equivalent (ClCF 2 CO) 2 O and M2 (Path “b”), 50 L/M Dilution, 0.15 Eq. TEAI
[0070] A catalyst stock solution was prepared by mixing 1.03 g of [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium (M2 catalyst) and 100.82 mL DCM at room temperature under nitrogen in an EasyMax reactor.
[0071] A stock solution of the acylated diene was prepared in a 250 mL 4-neck round bottom flask by mixing 148.85 mL of DCM solution containing 72.014 mmoles of compound (1), 57.61 mL DCM and 25.12 mL of chlorodifluoroacetic anhydride. The mixture was stirred at room temperature for 30 minutes, and diluted to an end volume of 200 mL. In a 5 L round bottom flask equipped with mechanical stirring, reflux condenser, thermometer and inlet for the addition cannulae, 2.78 g of tetraethylammonium iodide were mixed with 3.36 L of DCM. The mixture was then heated to reflux with stirring. From a syringe pump, 100 mL of the above catalyst stock solution were added over 2 hours 30 minutes. From a second syringe pump, 200 mL of the stock solution of the acylated diene was added over 2 hours (addition from the second syringe pump was started 15 minutes after the start of the first syringe pump). After termination of the addition, the mixture was further stirred at reflux for 10 hours. After cooling to room temperature, the reaction mixture was treated with a solution of 2-mercaptonicotinic acid (1.68 g) in 40% aqueous dimethylamine solution (3.17 mL), and stirred at room temperature for 2 hours. 540.10 mL of water were added, the stirring was stopped and the phases were separated. The organic layer was washed with 410.48 mL of water, separated, evaporated to a total volume of 274.11 mL and transferred to a 500 ml 4-neck RBF for the crystallization procedure.
[0072] The mixture was further evaporated while 2-butanone was gradually added to reach an internal temperature of 79.6° C. (total 2-butanone volume 279.83 mL). The mixture was cooled to 75° C., seeded and allowed to cool. The precipitate was filtered, washed consecutively with 28.81 mL of 2-butanone and with 2 portions of 28.81 mL of EtOH. The filter cake was dried at 60° C. for 71.75 hours to give 33.88 g of product compound (2), 69.71% isolated yield. Physical and chemical characterization data of this compound were consistent with the data reported in WO-2007/014926 in Example 4 Step E on page 74.
DESCRIPTION OF THE DRAWINGS
[0073] FIG. 1 : conversion of diethyldiallylmalonate (DEDAM) by M2 catalyst in the presence and absence of tetrabutylammonium iodide (TBAI) | The present invention relates to an improved process for preparing (2R,3aR,10Z,11aS,12aR,14aR)-cyclopenta[c]cyclopropa[g][1,6]diazacyclotetradecine-12a(1H)-carboxylic acid, 2,3,3a,4,5,6,7,8,9,11a,12,13,14,14a-tetradecahydro-2-[[7-methoxy-8-methyl-2-[4-(1-methylethyl)-2-thiazolyl]-4-quinolinyl]oxy]-5-methyl-4,14-dioxo-, ethyl ester. This compound is an intermediate in the overall synthesis route of the macrocyclic compound TMC 435. TMC 435 is an inhibitor of NS3/4A protease which plays an important role in the replication of the hepatitis C virus. | 2 |
BACKGROUND OF INVENTION
The present invention relates to the field of integrated circuits; more specifically, it relates to double data rate (DDR) dynamic random access memory (DRAM) burn-in testing.
Two main types of DRAMs are, single data rate (SDR) and a double data rate (DDR). In SDR mode, data comes out of the DRAM on a rising clock edge. In DDR mode, data is delivered externally on both a rising and falling clock edge. Furthermore, DDR architecture requires a two clock internal write latency (the number of clocks of delay from when the write command is issued to the DRAM externally until the column select is activated in the DRAM array), while SDR requires no internal write latency. Insitu burn-in testing of a DRAM in DDR mode, therefore, takes a significantly longer time than in SDR mode and can exceed the retention time specification of the DRAM cell, generating false fails. Current testing methods of dual mode (SDR and DDR) DRAMs therefore rely only on insitu burn-in testing of the DRAM in SDR mode. However, for DRAMs having only DDR mode circuitry, insitu burn-in testing is problematical. Therefore, a method of insitu pattern burn-in testing of DDR mode only DRAMs is required.
SUMMARY OF INVENTION
A first aspect of the present invention is a method for testing a DDR DRAM having a test mode and an operational mode, comprising in the order recited: (a) placing the DDR DRAM in test mode; (b) issuing a bank activate command to select and bring up a wordline selected for write of the DDR DRAM; (c) writing with auto-precharge, a test pattern to cells of the DDR DRAM; (d) repeating steps (b) and (c) until all wordlines for write have been selected; (e) issuing a bank activate command to select and bring up a wordline selected for read of the DDR DRAM; (f) reading with auto-precharge, the stored test pattern from cells of the DDR DRAM; and (g) repeating steps (e) and (f) until all wordlines for read have been selected.
A second aspect of the present invention is a DDR DRAM having a low frequency and a high frequency operating mode, comprising: a multiplicity of storage cells arranged in an array, each storage cell accessible by a wordline and a bitline; and wherein peripheral logic circuits of the DDR DRAM are adapted to execute a write burst enable and a column address command one clock cycle earlier in low frequency operating mode than in high frequency operating mode, adapted to execute an auto-precharge enable one-half clock cycle earlier in low frequency operating mode than in high frequency operating mode, and having a column address latency of one clock cycle in test mode and two or three clock cycles in operational mode.
A third aspect of the present invention is a computer system comprising a processor, an address/data bus coupled to the processor, and a computer-readable memory unit adapted to be coupled to the processor, the memory unit containing instructions that when executed by the processor implement a method for testing a DDR DRAM having a test mode and an operational mode, the method comprising the computer implemented steps of, in the order recited: (a) placing the DDR DRAM in test mode; (b) issuing a bank activate command to select and bring up a wordline selected for write of the DDR DRAM; (c) writing with auto-precharge, a test pattern to cells of the DDR DRAM; (d) repeating steps (b) and (c) until all wordlines for write have been selected; (e) issuing a bank activate command to select and bring up a wordline selected for read of the DDR DRAM; (f) reading with auto-precharge, the stored test pattern from cells of the DDR DRAM; and (g) repeating steps (e) and (f) until all wordlines for read have been selected.
BRIEF DESCRIPTION OF DRAWINGS
The features of the invention are set forth in the appended claims. The invention itself, however, will be best understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
FIG. 1 is a timing diagram for a related art method of performing a pattern burn-in test of a DRAM in SDR mode;
FIG. 2 is a timing diagram for a related art method of performing a pattern burn-in test of a DRAM in DDR mode;
FIG. 3 is a timing diagram for a method of performing a pattern burn-in test of a DRAM in DDR mode according to the present invention;
FIG. 4 is a flowchart for the method of performing a pattern burn-in test of a DRAM in DDR mode according to the present invention; and
FIG. 5 is a schematic block diagram of a general-purpose computer for directing a tester in the performance of the present invention.
DETAILED DESCRIPTION
Cells in a DRAM are arranged in a two dimensional matrix, with rows being accessed by wordlines and columns being accessed by bitlines. A typical DRAM cell consists of an N channel field effect transistor (NFET) transistor and a storage node (usually a capacitor). The gate of the NFET is connected to a wordline, the drain to a bitline, the source to a first plate of the capacitor and the second plate of the capacitor is connected to a low voltage, usually to ground. Sense amplifiers on each bitline sense the presence of stored charge (a logical 1) on the storage node of a DRAM cell when that cells wordline is turned on.
Operation of a DRAM in SDR/DDR mode is covered in the JEDEC Standards SDRAM3 — 11 — 05/JESD97 specification. The circuit design to meet this specification varies from manufacturer to manufacturer.
Burn-in testing of DRAMs is designed to provide accelerated fail of cells during test that would otherwise fail subsequently. Acceleration is accomplished by performing the test at elevated temperature, typically about 140° C. or 180° C., and when many DRAMs are tested in parallel, slows down I/O operations. However this slows down operation of the DRAM, so a slow clock time is used. An example of a slow clock time is 120 ns or 0.83 MHz, even though the DRAM may be designed for higher frequency operation, for example 100 MHz (10 ns CLK) or higher. Any slow clock time of less than 100% of the normal CLK time may be used. Burn-in insitu stress pattern test is performed by writing patterns into the DRAM cells and then reading out the DRAM cells some time later. First all cells are written and then all cells are read. If the input pattern does not match the output pattern, a fail has occurred.
FIG. 1 is a timing diagram for a related art method of performing a pattern burn-in test of a DRAM in SDR mode. In FIG. 1 , each write sequence takes three clock cycles. A bank activate (BA) command is issued on the rising edge of the first clock and data (designated by signal DQ) is presented and a write (WR) command is issued and the data latched at the rising edge of the second clock cycle. At the rising edge of the third clock cycle, a precharge (PRE command) is issued. A BA command brings up a single wordline. A WR command places data on the bitlines, and a PRE command, precharges the bitline to a known state so the bitline is ready for the next WR command.
After all cells have been written, they are read out. Each read sequence takes four clock cycles. At the rising edge of the first clock, a BA command is issued and at the rising edge of the second clock a read (RD) command is issued. However, data is not present at the output of the DRAM until the rising edge of the fourth clock. This is read column address select (CAS) latency of the DRAM. A PRE command is issued on the rising edge of the fourth clock (after the data has been sensed) so the bitline is in a known state and ready for the next RD command.
An important consideration is the retention time of the DRAM cell. Since all DRAM cells are written sequentially and then read sequentially, the amount of time data written to each cell can exceed the retention time of the DRAM cell. For example given a 120 ns clock cycle, 8192 wordlines, a 3 clock write cycle and a 4 clock read cycle, data in the very first DRAM cell written has been held by that cell for about 2.95 milliseconds (120 ns×3×8192) before being read and the very last DRAM cell written has been held for about 2.96 milliseconds ((120 ns×3×8192)+(8192−1) before being read. Given a typical burn-in retention time specification of about 3 milliseconds, there is no retention time problem. However, if the clock cycle is 160 ns, then the times are 3.93 (160 ns×3×8192) milliseconds and 3.94 ((120 ns×3×8192)+(8192−1) milliseconds respectively there is a retention time problem.
FIG. 2 is a timing diagram for a related art method of performing a pattern burn-in test of a DRAM in DDR mode. In FIG. 2 , each write sequence takes five clock cycles. A BA command is issued on the rising edge of the first clock. A WR is issued on the rising edge of the second clock. First data is presented and a first DQS issued during the rising edge of the third clock cycle. Second data is presented and a second DQS issued during the falling edge of the third clock cycle. Both first and second data are latched at the fourth clock cycle. These extra clock cycles between presentation of data and latching of data into the DRAM array are the internal write latency of the DRAM in DDR mode. During the rising edge of the fifth clock cycle, a PRE command is issued precharging the bitline to a known state so the bitline is ready for the next write command.
After all cells have been written, they are read out. Each read cycle takes four clock cycles. At the rising edge of the first clock a bank activate command is issued and at the rising edge of the second clock a RD command is issued. However, data is not present at the output of the bitline amplifiers until the rising edge of the fourth clock. This is again, the read CAS latency of the DRAM. A PRE command is issued on the rising edge of the fourth clock (after the data has been sensed) so the bitline is in a known state and ready for the next read command.
Again, the retention time specification must be considered. For example given a 160 ns clock cycle, 8192 wordlines, a 5 clock write cycle and a 4 clock read cycle, data in the very first DRAM cell written (which is the worst case) has been held by that cell for about 6.6 milliseconds (160 ns×5×8192) before being read. Given a typical burn-in retention time specification of about 3 milliseconds, there is a retention time problem. Examining the 120 ns clock cycle case, data in the very first DRAM cell written has been held by that cell for about 4.9 milliseconds (120 ns×5×8192) before being read. Again, there is a retention time problem.
The present invention requires a DDR DRAM switchable between a normal and burn-in mode. The burn-in mode requires functional modification of the DRAM peripheral logic circuits to change the timing of commands for external WR latency, RD CAS latency, WR Burst enable (WBE) and AP in burn-in mode but retain the specified timings in normal mode. The exact circuit modifications can vary from DRAM design to design; therefore, the changes are described in terms of circuit function. One of ordinary skill in the art would know how to modify a DRAM DDR circuit design to effect the changes to the timing of commands for WR latency, RD CAS latency, WR Burst enable (WBE) and AP in order to practice the present invention.
FIG. 3 is a timing diagram for a method of performing a pattern burn-in test of a DRAM in DDR mode according to the present invention. In FIG. 3 , each write cycle takes two clock cycles. A BA command is issued on the rising edge of the first clock. A WR with auto-precharge (AP) command is issued on the rising edge of the second clock. First data is presented and a first DQS issued during the rising edge of the second clock cycle. Second data is presented and a second DQS issued during the falling edge of the second clock cycle. Both first and second data are latched during the second clock cycle. This removes the write latency of the DRAM otherwise present in DDR mode. The WR/AP command eliminates the need for a PRE command to be is issued to bring the bitline to a known state preparatory for the next write command. Two additional signals in FIG. 3 are the auto-precharge reset (APR) and WBE. WBE is issued just after the rising edge of the second clock and is completed before the falling edge of the second clock. APR is issued at the falling edge of the second clock and is completed before the rising edge of the first clock of the next write sequence.
After all cells have been written, they are read out. Each read sequence takes two clock cycles. At the rising edge of the first clock a bank activate command is issued and at the rising edge of the second clock a RD/AP command is issued. However, data is not present at the output of the bitline amplifiers until the rising edge of the first clock of the next read sequence. Thus, the RD CAS latency of the DRAM has been reduced from 2 to one clock cycles. A precharge command is issued on the falling edge of the second clock (after the data has been sensed) so the bitline is in a known state and ready for the next read command. The WR/AP command eliminates the need for a PRE command to be issued to bring the bitline to a known state preparatory for the next read command.
Again, the retention time specification must be considered. For example given a 120 ns clock cycle, 8192 wordlines, a 2 clock write cycle and a 2 clock read cycle, data in the very first DRAM cell written (which is the worst case) has been held by that cell for about 2.0 milliseconds (120 ns×2×8192) before being read. Given a typical burn-in retention time specification of about 3 milliseconds, there is no longer a potential retention time problem burning in a DDR DRAM. In the example of a 160 ns clock cycle, data in the very first DRAM cell written (has been held by that cell for about 2.6 milliseconds (160 ns×2×8192) before being read. Again, there is no longer a potential retention time problem burning in a DDR DRAM.
There are four functional modifications of the DDR DRAM peripheral logic circuits required to practice the present invention as summarized in Table I.
TABLE I
Mod
Result of
Cycle
#
Modification
Reduction
Logic Circuit Modification
1
Eliminate 1 CLK
1 CLK per
Shift WBE, BASEL and
WR latency
WR command
CADD one CLK earlier
(BASEL = BA select)
(CADD = Column address)
2
Reduce RD CAS
1 CLK per
Eliminate 1 CLK of FIFO
latency from 2 to 1
RD command
shifting (Change CAS
CLK
latency from 2 or 3 CLKs
to 1 CLK
3
Latch data same
1 CLK per
Same as (1)
CLK it is received
WR command
4
Time AP off
1 CLK per
No PRE command used
falling edge of CLK
RD/WR
command
The first modification eliminates the DDR write latency of 1 clock cycle from the DDR DRAM specification. The write latency is a power saving feature of the DDR DRAM specification that powers up the data receiving circuits of the DRAM only when need to receive external data. Since this is not an issue in burn-in mode, the write latency can be eliminated from the write sequence saving one clock cycle.
The second modification reduces the RD CAS latency from 2 CLK cycles to 1 CLK cycle. In normal mode the DDR DRAM array access time is not fast enough to allow a CAS latency of 1 CLK cycle at normal operating frequencies of 100 MHz or more. However, since burn-in is run at 0.83 MHz the access time of the array is not an issue. The long clock time (for example, 120 ns) used in burn-in offers a considerable timing margin for DRAM array access even with a RD CAS latency of 1 CLK cycle.
The third modification allows data to be latched into the DRAM array via the column select line (CSL) in the same clock cycle that data is received in. In normal mode, the DDR DRAM waits until the next rising edge after the last bit of data (which is always on a falling CLK edge) to latch the data into the DRAM array and start the write-back. The long burn-in CLK cycle time not only allows the write back to start earlier, but ensures that it will complete before the next CLK falling edge. Thus, 1 CLK cycle can be eliminated from the write sequence.
The fourth modification launches the auto-precharge from a CLK falling edge immediately after data write. (In burn-in mode, the auto-precharge is started a half CLK cycle earlier than in normal mode.) Depending on whether Timed Address Compression (TAC) is used or not, data may be “received” on a CLK rising edge (TAC mode) or both the rising and falling edges of the CLK (non-TAC mode). In TAC mode, the precharge is initiated immediately after the falling edge of the CLK because there is no data and hence no write-back delay is required. In non-TAC mode, a timer is used to allow enough time for the write-back and to start the auto-precharge asynchronously after the falling edge of a CLK. Half of the burn-in CLK time (for example, 60 ns) is more than enough time to accomplish both write-back and precharge, allowing a bank activate (and hence the beginning of a new write sequence) to occur on the next CLK rising edge. The long burn-in CLK cycle is long enough to complete a bitline precharge before the next CLK rising edge as well. Thus, by issuing a write with auto-precharge in non-TAC mode, a further reduction of the write sequence by 1 CLK cycle may be obtained. Read with auto-precharge in non-TAC mode may also be used.
FIG. 4 is a flowchart for the method of performing a pattern burn-in test of a DRAM in DDR according to the present invention. The flowchart starts after a DRAM device has been brought up to burn-in temperature and has been connected to a tester. In step 100 a bank activate command is issued to activate the first/next wordline of the DRAM based on the address of the first/next wordline. In step 105 , a test pattern from a test pattern file 110 is written to the bitlines of the DRAM array with auto-precharge. In step 115 , it is determined if another wordline (WL) remains to be activated. If another wordline remains to be activated, then in step 120 the address of the next wordline is determined and the method loops back to step 100 , otherwise the method proceeds to step 125 . Each sequence of steps 100 through 120 consumes 2 burn-in CLK cycles.
In step 125 a bank activate command is issued to activate the first/next wordline of the DRAM based on the address of the first/next wordline. In step 130 , the pattern stored on the activated wordline is read out through the bitlines of the DRAM and written to an output pattern file 135 . In step 140 , it is determined if another wordline (WL) remains to be activated. If another wordline remains to be activated, then in step 145 the address of the next wordline is determined and the method loops back to step 125 , otherwise the method ends. Each sequence of steps 125 through 145 consumes 2 burn-in CLK cycles. Afterwards, the output patterns can be compared to the inputted test patterns to determine which DRAM cells are connected to defective wordlines or bitlines. Often these “defective” DRAM wordlines or bitlines can be replaced with known good redundant wordlines or bitlines.
Generally, the method described herein with respect to a method of performing an insitu pattern burn-in test of a DRAM in DDR mode is practiced by a tester under the control of a general-purpose computer and the method may be coded as a set of instructions on removable or hard media for use by the general-purpose computer. FIG. 5 is a schematic block diagram of a general-purpose computer for directing a tester 150 connected to a DRAM in a burn-in oven 155 in the performance of the present invention. In FIG. 5 , computer system 200 has at least one microprocessor or central processing unit (CPU) 205 . CPU 205 is interconnected via a system bus 210 to a random access memory (RAM) 215 , a read-only memory (ROM) 220 , an input/output (I/O) adapter 225 for a connecting a removable data and/or program storage device 230 and a mass data and/or program storage device 235 , a user interface adapter 240 for connecting a keyboard 245 and a mouse 250 , a port adapter 255 for connecting a data port 260 and a display adapter 265 for connecting a display device 270 .
ROM 220 contains the basic operating system for computer system 200 . The operating system may alternatively reside in RAM 215 or elsewhere as is known in the art. Examples of removable data and/or program storage device 230 include magnetic media such as floppy drives and tape drives and optical media such as CD ROM drives. Examples of mass data and/or program storage device 235 include hard disk drives and non-volatile memory such as flash memory. In addition to keyboard 245 and mouse 250 , other user input devices such as trackballs, writing tablets, pressure pads, microphones, light pens and position-sensing screen displays may be connected to user interface 240 . Examples of display devices include cathode-ray tubes (CRT) and liquid crystal displays (LCD).
The DDR DRAM of the present invention may be used as a low frequency (or switchable low/high frequency) DDR DRAM in applications, for example, requiring very low power consumption. In one example low frequency operational mode is less than about 33 MHz and high frequency operational mode is greater than about 83 MHz.
A computer program with an appropriate application interface to tester 150 may be created by one of skill in the art and stored on the system or a data and/or program storage device to simplify the practicing of this invention. In operation, information for or the computer program created to run tester 150 is loaded on the appropriate removable data and/or program storage device 230 , fed through data port 260 or typed in using keyboard 245 .
Thus, the present invention provides a method of insitu pattern burn-in testing of DDR mode only DRAMs.
The description of the embodiments of the present invention is given above for the understanding of the present invention. It will be understood that the invention is not limited to the particular embodiments described herein, but is capable of various modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, it is intended that the following claims cover all such modifications and changes as fall within the true spirit and scope of the invention. | A DDR DRAM having a test mode and an operational mode and a method for testing the DDR DRAM. The method includes in the order recited: (a) placing the DDR DRAM in test mode; (b) issuing a band activate command to select and bring up a wordline selected for write of the DDR DRAM; (c) writing with auto-precharge, a test pattern to cells of the DDR DRAM; (d) repeating steps (b) and (c) until all wordlines for write have been selected; (e) issuing a bank activate command to select and bring up a wordline selected for read of the DDR DRAM; (f) reading with auto-precharge, the stored test pattern from cells of the DDR DRAM; and (g) repeating steps (c) and (f) until all wordlines for read have been selected. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to memory devices generally and, more particularly, to a method and/or apparatus for implementing a low power content addressable memory (CAM) hitline precharge and sensing circuit.
BACKGROUND OF THE INVENTION
[0002] Conventional content addressable memories (CAMs) use a wide NOR structure. In the conventional architecture, a single positively-doped field effect transistor (PFET) device and a large number of CAM core cells with negatively-doped field effect transistor (NFET) pull-down devices are connected together by a hitline (or matchline). The hitline is also connected to an input of a sensing inverter. The PFET device precharges the hitline to a supply voltage (VDD) and is turned off. If there is a mismatch (or miss), one or more of the core pull-down NFET devices are turned on and the hitline discharges to a ground potential (VSS). If all the bits match (or hit) the hitline remains charged. The sensing inverter senses whether the bits on the hitline are a hit or miss and buffers the information to a next block of logic.
[0003] The conventional architecture is area efficient and fast. However, a disadvantage of the conventional architecture is the large dynamic power consumed. Conventional content addressable memories (CAMs) consume large amounts of power during compare operations. The power used during compare operations is more than the power used during read or write operations. In most CAM memories, a vast majority of the time is spent performing compare operations. One-third of the power used by the conventional CAM can be consumed in the precharging of the hitline alone. Thus, reducing overall power usage for compare operations can help reduce overall maximum power.
[0004] It would be desirable to implement a low power CAM hitline precharge and sensing circuit.
SUMMARY OF THE INVENTION
[0005] Embodiments of the invention include a driver circuit and a memory circuit. The driver circuit may be configured to precharge a hitline in response to a predetermined voltage level and a control signal and sense a result of a compare operation based upon a hitline signal on the hitline. The driver circuit generally precharges the hitline to a voltage level lower than the predetermined voltage level and senses the result of the compare operation using the full predetermined voltage level. The memory circuit may be configured to perform the compare operation using the hitline.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Embodiments of the invention will be apparent from the following detailed description and the appended claims and drawings in which:
[0007] FIG. 1 is a block diagram illustrating a memory including a hitline precharge and sensing circuit in accordance with an example embodiment of the present invention;
[0008] FIG. 2 is a circuit diagram illustrating an example hitline precharge and sensing circuit implemented in accordance with an embodiment of the present invention;
[0009] FIG. 3 is a circuit diagram illustrating another example of a hitline precharge and sensing circuit implemented accordance with an embodiment of the present invention; and
[0010] FIG. 4 is a block diagram illustrating an example of a CAM memory core comprising a plurality of hitlines and hitline precharge and sensing circuits implemented in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Referring to FIG. 1 , a diagram of a circuit 100 is shown illustrating a content addressable memory (CAM) with a hitline precharge and sensing circuit in accordance with an embodiment of the invention. The circuit 100 may comprise a block (or circuit) 102 and a block (or circuit) 104 . The block 102 may implement a hitline precharge and sensing circuit in accordance with an embodiment of the present invention. The block 104 may implement a portion of a memory core. The block 104 may comprise a number of NOR-based content addressable memory (CAM) bit cells 104 a - 104 n . The CAM bit cells 104 a - 104 n may be connected to a hitline 105 . A complete memory core of the circuit 100 may comprise a plurality of blocks 104 and associated hitlines, where each of the hitlines may be connected to a respective one of a plurality of blocks 102 .
[0012] The circuit 100 generally has three main operations—read, write, and compare. A write operation is normally used to load data into the block 104 . A read operation may allow a user to verify the contents of each address of the block 104 . The compare operation may be used to compare dat a -in bits to the contents stored in the block 104 . The compare operation may provide a user with an output identifying which, if any, of the entries in the block 104 match the dat a -in bits. Determining whether any of the entries in the block 104 match the dat a -in bits generally involves pre-charging the hitline 105 to a pre-charged state and sensing a change in the pre-charged state in response to the compare operation. The block 102 generally handles the pre-charging and sensing operations.
[0013] The block 102 may have an input 106 that may receive a signal (e.g., HL) from the hitline 105 and an output 108 that may present a signal (e.g., MATCH). The signal HL may be referred to as a hitline signal. The signal MATCH may be configured to indicate whether a compare operation with the number of content addressable memory cells 104 a - 104 n has resulted in a hit or a miss. Each of the content addressable memory cells 104 a - 104 n may be connected to the hitline 105 . In one example, the circuit 100 may comprise a plurality of the blocks 102 and 104 coupled accordingly.
[0014] Conventional NOR-based CAMs precharge hitlines to full rail (e.g., VDD). The block 102 generally precharges the hitline 105 to a voltage level slightly higher than one-half the supply voltage of the circuit 102 (e.g., ˜VDD/2 for the case where the supply voltage is VDD). The block 102 reduces the dynamic power consumed by a CAM and provides faster sensing of a miss. By reducing the dynamic power, the block 102 generally provides a significant total dynamic power savings for the entire memory. By sensing a miss faster, the block 102 increases the frequency at which the entire memory operates. For example, when a single bit miss occurs, only one bit cell is pulling down the entire hitline 105 . The hitline 105 is generally highly capacitive. Because the hitline 105 is highly capacitive, the slew rate of the signal HL on a miss may be very slow. Since the starting point of signal HL in a memory implemented in accordance with an embodiment of the invention is lower (e.g., ˜VDD/2), the amount of time taken to trigger a miss is generally much shorter, therefore speeding up the entire circuit and memory.
[0015] Referring to FIG. 2 , a more detailed diagram of the circuit 100 is shown illustrating an example implementation of the hitline precharge and sensing circuit in accordance with an embodiment of the invention. A typical CAM bit cell 104 i illustrated in FIG. 2 , corresponding to CAM bit cells 104 a - 104 n in FIG. 1 , may comprise a transistor 110 , a transistor 112 and a memory bitcell (not shown). The transistors 110 and 112 may be implemented as NFETs and the memory bitcell may be implemented as a six transistor (6T) static random access memory (SRAM) cell (not shown). A drain of the transistor 110 is connected to the hitline 105 . A gate of the transistor 110 receives a signal (e.g., HBL). The signal HBL may be implemented as a hit bitline signal. A source of the transistor 110 may be connected to a drain of the transistor 112 . A gate of the transistor 112 may be connected to an internal node of the memory bitcell. A source of the transistor 112 may be connected to a power supply ground potential.
[0016] In one example, the block 102 may comprise a transistor 120 , a transistor 122 , a transistor 124 , a logic gate 126 , a logic gate 128 , a transistor 130 , a transistor 132 , and a transistor 134 . The transistors 120 , 122 , 124 , and 134 may be implemented as NFETs.
[0017] The transistors 130 and 132 may be implemented as PFETs. The logic gate 126 may be implemented, in one example, as an inverter. The logic gate 128 may be implemented, in one example, as an inverter. A source of the transistor 122 may be connected to a source of the transistor 124 and a drain of the transistor 122 may be connected to a drain of the transistor 124 to form a transmission or pass gate. The transistors 132 and 134 may be connected to form a complementary metal-oxide-semiconductor (CMOS) inverter 136 .
[0018] In general, the transistors 122 and 124 are implemented such that the transistor 122 has a voltage threshold (e.g., LVT) that is lower than a voltage threshold (e.g., HVT) of the transistor 124 (e.g., LVT<HVT). In general, any technique available that provides the transistor 122 with a lower voltage threshold than the transistor 124 may be employed. In one example, the transistor 122 may be implemented using a device from a lower voltage threshold cell library and the transistor 124 may be implemented using a device from a higher voltage threshold cell library. For example, the transistors 122 and 124 may be implemented using processes that support multiple voltage thresholds (e.g., multi-VT). The multi-VT processes may have more than one VT adjustment processing step. In general, VT adjustment is done by ion implantation into a channel region of the transistor: few ions are implanted for a high-VT transistor, a bit more ions are implanted for a medium-VT transistor, and the most ions are implanted for a low-VT transistor. High-VT devices are generally part of a low leakage power library. High-VT devices are generally for low power use, but low critical timing. Medium-VT devices are generally part of a middle leakage power library. Medium-VT devices are typically for general purpose use. Low-VT devices are generally part of a big leakage power library. Low-VT devices are generally used for timing critical paths. In some alternative embodiments, the difference in voltage thresholds between the transistor 122 and the transistor 124 may be accomplished by implementing the transistors with different lengths. For example, the transistor 122 may be implemented having a first length (e.g., L) and the transistor 124 may be implemented having a second length (e.g., K*L, K>1). In still other embodiments, the difference in voltage thresholds between the transistor 122 and the transistor 124 may be accomplished by implementing the transistors with different bulk voltages, or a combination of the multi-VT devices, different lengths and different bulk voltages. In general, the voltage thresholds of the transistors other than the transistors 122 and 124 are not critical and, therefore, the other transistors may be implemented using any devices available.
[0019] The hitline 105 is connected to a drain of the transistor 120 and the sources of the transistors 122 and 124 . A gate of the transistor 120 receives a signal (e.g., HLDCHRG). A source of the transistor 120 is connected to the power supply ground potential. A gate of the transistor 122 is connected to an output of the logic gate 126 . A gate of the transistor 124 is connected to the power supply voltage of the block 102 (e.g., VDD). A signal (e.g., HLRES) is presented to an input of the logic gate 128 . An output of the logic gate 128 may present a signal (e.g., HLPCHRGN). The signal HLPCHRGN may be presented to an input of the logic gate 126 and a gate of the transistor 130 . A source of the transistor 130 is connected to the power supply voltage of the block 102 . A drain of the transistor 130 , the drains of the transistors 122 and 124 , a gate of the transistor 132 and a gate of the transistor 134 are connected, forming a sensing node 138 at which a signal (e.g., INVSENSE) may be presented (or developed). The signal INVSENSE generally represents a voltage level of the sensing node 138 . A source of the transistor 132 is connected to the power supply voltage of the block 102 . A source of the transistor 134 is connected to the power supply ground potential. A drain of the transistor 132 is connected to a drain of the transistor 134 , forming a node 140 at which a signal (e.g., HLN) may be presented. The signal HLN, with at least one of the transistors 122 and 124 in a conductive state, is generally the complement of the signal HL. The signal HLN may be used as an output of the block 102 . Alternatively, the signal HLN may be buffered prior to being used as an output (described below in connection with FIG. 3 ).
[0020] While an embodiment of the invention is illustrated and described as charging a hitline using a supply voltage, one skilled in the art would recognize that a predetermined voltage level other than the supply voltage but large enough to achieve the function of pre-charging the hitline, accounting for losses in transistors, could be used. Such an alternative voltage level could be less than the supply voltage.
[0021] The block 102 generally provides a sensing voltage differential. The block 102 is generally configured to allow the signal INVSENSE at the sensing node 138 to stay at the full supply voltage (e.g., VDD) when the hitline 105 is at about VDD/2.
[0022] Because the signal INVSENSE at the sensing node 138 remains at the full supply voltage, the voltage margin lost with a precharge of ˜VDD/2 is restored for the hit case. If the sense inverter 136 was connected to the hitline 105 directly and there was a hit, any noise on the hitline 105 might make the transistor 132 turn on and register a false miss. The architecture of the sensing circuit in accordance with an embodiment the invention generally makes the hit case as robust as if the hitline 105 were precharged to the full rail (e.g., VDD).
[0023] Both of the transistors 122 and 124 are used for precharge, while only the transistor 124 is used for sensing. The effective voltage threshold difference between the one device conducting and the two devices conducting generally creates a sense margin that ensures both a “1” and a “0” are sensed correctly. The transistors 122 and 124 , when used together, have a lower effective device voltage threshold and, therefore, precharge the hitline 105 to a higher level than would be obtained using only the single device, transistor 124 . During sensing, the single device, transistor 124 , is used, which causes the switch level of the sense inverter 136 to be lower.
[0024] The precharging of the hitline 105 to ˜VDD/2 is generally performed as follows. The hitline 105 generally starts at the power supply ground potential (e.g., VSS=0V). When a compare operation is triggered the signal HLRES is pulsed high turning on the transistor 122 and the transistor 130 . The signal INVSENSE goes to the full supply voltage (e.g., VDD) and the hitline signal HL starts charging HIGH. The hitline 105 can only charge to a maximum of the supply voltage of the block 102 minus the voltage threshold of the transistor 122 (e.g., VDD-LVT) because of the voltage drop across the transistor 122 . The hitline signal HL does not generally get to the VDD-LVT level because of the high capacitance of the hitline 105 and a pulse duration of the signal HLRES being purposely kept short, thus reducing charging time. After the signal HLRES transitions LOW, the signal HBL in the typical bit cell 104 i may switch HIGH, activating the compare portion of the operation.
[0025] The precharge happens as described above and when the signal HLRES is LOW the transistor 122 is OFF. The signal INVSENSE at the sensing node 138 is generally at the full supply voltage (e.g., VDD) and the hitline signal HL is generally at a voltage level of approximately one-half the supply voltage (e.g., ˜VDD/2). When there is a hit, the hitline signal HL remains at the voltage level of approximately VDD/2. The only remaining path between the hitline 105 and the sensing node 138 is the transistor 124 . In order for the transistor 124 to fully conduct there needs to be a voltage difference between the source and drain of the transistor 124 that is greater than the particular threshold voltage (e.g., HVT) of the transistor 124 . Therefore, when the difference between the voltage level of the signal INVSENSE at the sensing node 138 (e.g., V(INVSENSE)) and the voltage level of the hitline signal HL (e.g., V(HL)) is less than the threshold voltage of the transistor 124 (e.g., V(INVSENSE)−V(HL)<HVT), very little current passes through the transistor 124 . Because very little current passes through the transistor 124 , the transistor 124 remains in a nonconductive, LOW, or OFF state and the gates of the transistors 132 and 134 in the sense inverter 136 remain charged at VDD. Because the gates of the transistors 132 and 134 in the sense inverter 136 are charged at VDD, extra margin is generally provided for sensing the hit case even though the hitline signal HL is at a voltage level that is lower than the full supply voltage.
[0026] If there is a miss, when the signal HBL switches HIGH the hitline signal HL starts to be pulled down. When the difference between the voltage at the sensing node 138 and the voltage on the hitline 105 is greater than the threshold voltage of the transistor 124 (e.g., V(INVSENSE)−V(HL)>HVT), the transistor 124 starts conducting and the sensing node 138 is pulled LOW. When the voltage level of the signal INVSENSE at the sensing node 138 becomes low enough (e.g., VDD−V(INVSENSE)>VT of the transistor 132 ), the transistor 132 turns on, causing the signal HLN to transition HIGH, signaling a miss. At the end of the compare cycle, whether there is a hit or a miss, the signal HLDCHRG transitions HIGH to pull the hitline 105 and the sensing node 138 back to the ground potential (e.g., VSS). Discharge of the hitline 105 back to the ground potential VSS is important because if there is a hit and the hitline 105 stayed at ˜VDD/2, after multiple cycles of hits the voltage level of the hitline 105 may get charged to a higher voltage level than anticipated. The higher voltage level would take longer to sense the miss case (e.g., the falling slew rate of the hitline signal HL is very slow because of the high capacitance of the hitline 105 ) and the compare operation may falsely sense a hit when a miss should have been sensed.
[0027] Referring to FIG. 3 , a more detailed diagram of a circuit 100 ′ is shown illustrating an example implementation of a hitline precharge and sensing circuit 102 ′ in accordance with another embodiment of the invention. The circuit 102 ′ may be implemented similarly to the block 102 , except that a shoot through control device (e.g., a transistor 150 ) may be included and the signal HLN may be buffered by adding two inverters 152 and 154 after the node 140 to generate a signal (e.g., HLNB). The shoot through control device limits the dynamic power of the sensing portion of the circuit 102 ′. The circuit 102 ′ may increase noise immunity and decrease dynamic power. A sense inverter 160 of the circuit 102 ′ generally includes stacked PFET devices (e.g., transistors 132 and 150 ) to decrease shoot-through current in the sense inverter 160 during precharge. The stacked PFET devices also lower the switch point of the sense inverter 160 making the hit case more robust. The inverters 152 and 154 added after the sense inverter 160 may also lower the switch point of the sense inverter 160 . The lower switch point of the sense inverter 160 provided by the addition of the two inverters 152 and 154 also increases the speed of sensing a miss.
[0028] Referring to FIG. 4 , a block diagram of a circuit 200 is shown illustrating a CAM memory core implemented in accordance with an embodiment of the present invention. In one example, a complete memory core may comprise a CAM array 202 and a match circuit 204 .
[0029] The CAM array 202 may comprise a plurality of CAM cells arranged in a number of blocks 206 a - 206 n and associated with a number of hitlines 208 a - 208 n. Each of the hitlines 208 a - 208 n generally presents a respective hitline signal (e.g., HL[a]-HL[n]). Each of the hitlines 208 a - 208 n may be connected to a respective one of a plurality of hitline precharge and sensing circuits 210 a - 210 n in the match circuit 204 . The hitline precharge and sensing circuits 210 a - 210 n may be implemented in some embodiments of the invention using the circuit 102 (described above in connection with FIG. 2 ) and in other embodiments of the invention using the circuit 102 ′ (described above in connection with FIG. 3 ). Each of the hitline precharge and sensing circuits 210 a - 210 n may have an output that may present a respective signal (e.g., HLN[a]-HLN[n]). The signals HLN[a]-HLN[n] may be used by the circuit 204 to generate a signal (e.g., MATCH) indicating whether or not dat a -in bits are matched by contents of the CAM array 202 .
[0030] The circuits 100 and 200 are generally illustrated implementing a local hitline. It will be apparent to those skilled in the relevant art(s) that the precharging and sensing techniques described above may be used on a global hitline as well. Low power content addressable memory (CAM) hitline precharge and sensing circuits in accordance with embodiments of the present invention may (i) reduce a precharge level of a hitline, (ii) significantly reduce dynamic power consumption, (iii) provide faster sensing of misses, (iv) provide increased operating frequency of a CAM, (v) allow a sensing node to remain at the full supply voltage while the hitline is precharged to a voltage lower than the full supply voltage, (vi) provide a shoot through control device to limit dynamic power, and/or (vi) create a sense margin using NFET devices for ensuring that hits and misses are correctly sensed.
[0031] The various signals of the present invention are generally “ON” (e.g., a digital HIGH, or 1) or “OFF” (e.g., a digital LOW, or 0). However, the particular polarities of the ON (e.g., asserted) and OFF (e.g., de-asserted) states of the signals may be adjusted (e.g., reversed) to meet the design criteria of a particular implementation. Additionally, inverters may be added to change a particular polarity of the signals. It will be apparent to those skilled in the relevant art(s) that certain nodes of transistors and other semiconductor devices may be interchanged and still achieve some desired electrical characteristics. The node interchanging may be achieved physically and/or electrically. Examples of transistor nodes that may be interchanged include, but are not limited to, the emitter and collector of bipolar transistors, the drain and source of field effect transistors, and the first base and second base of unijunction transistors.
[0032] Embodiment of the invention may also be implemented by the preparation of ASICs (application specific integrated circuits), Platform ASICs, FPGAs (field programmable gate arrays), PLDs (programmable logic devices), CPLDs (complex programmable logic device), se a -of-gates, RFICs (radio frequency integrated circuits), ASSPs (application specific standard products), one or more integrated circuits, one or more chips or die arranged as flip-chip modules and/or multi-chip modules or by interconnecting an appropriate network of conventional component circuits, as is described herein, modifications of which will be readily apparent to those skilled in the art(s).
[0033] The terms “may” and “generally” when used herein in conjunction with “is(are)” and verbs are meant to communicate the intention that the description is exemplary and believed to be broad enough to encompass both the specific examples presented in the disclosure as well as alternative examples that could be derived based on the disclosure. The terms “may” and “generally” as used herein should not be construed to necessarily imply the desirability or possibility of omitting a corresponding element.
[0034] While the invention has been particularly shown and described with reference to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the scope of the invention. | An apparatus and a method of operating the apparatus. The apparatus includes a driver circuit and a memory circuit. The driver circuit may be configured to precharge a hitline in response to a predetermined voltage level and a control signal and sense a result of a compare operation based upon a hitline signal on the hitline. The driver circuit generally precharges the hitline to a voltage level lower than the predetermined voltage level and senses the result of the compare operation using the full predetermined voltage level. The memory circuit may be configured to perform the compare operation using the hitline. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending U.S. application Ser. No. 10/011,506, filed Nov. 5, 2001; which is a continuation-in-part of U.S. application Ser. No. 09/663,607, filed Sep. 18, 2000, now U.S. Pat. No. 6,721,597; and U.S. application Ser. No. 09/663,606, filed Sep. 18, 2000, now U.S. Pat. No. 6,647,292, the disclosures of which are all incorporated herein by reference.
[0002] In addition, this application is related to U.S. Application Serial. No. 10/011,860, filed Nov. 5, 2001; U.S. application Ser. No. 10/011,958, filed Nov. 5, 2001; and U.S. application Ser. No. 10/015, 202, filed Nov. 5, 2001, the disclosures of which applications are hereby incorporated by reference.
FIELD OF THE INVENTION
[0003] The present invention relates to an apparatus and method for performing electrical cardioversion/defibrillation and optional pacing of the heart via a non-transvenous system.
BACKGROUND OF THE INVENTION
[0004] Defibrillation/cardioversion is a technique employed to counter arrhythmic heart conditions including some tachycardias in the atria and/or ventricles. Typically, electrodes are employed to stimulate the heart with electrical impulses or shocks, of a magnitude substantially greater than pulses used in cardiac pacing. Shocks used for defibrillation therapy can comprise a biphasic truncated exponential waveform. As for pacing, a constant current density is desired to reduce or eliminate variability due to the electrode/tissue interface.
[0005] Defibrillation/cardioversion systems include body implantable electrodes that are connected to a hermetically sealed container housing the electronics, battery supply and capacitors. The entire system is referred to as implantable cardioverter/defibrillators (ICDs). The electrodes used in ICDs can be in the form of patches applied directly to epicardial tissue, or, more commonly, are on the distal regions of small cylindrical insulated catheters that typically enter the subclavian venous system, pass through the superior vena cava and, into one or more endocardial areas of the heart. Such electrode systems are called intravascular or transvenous electrodes. U.S. Pat. Nos. 4,603,705; 4,693,253; 4,944,300; and 5,105,810, the disclosures of which are all incorporated herein by reference, disclose intravascular or transvenous electrodes, employed either alone, in combination with other intravascular or transvenous electrodes, or in combination with an epicardial patch or subcutaneous electrodes. Compliant epicardial defibrillator electrodes are disclosed in U.S. Pat. Nos. 4,567,900 and 5,618,287, the disclosures of which are incorporated herein by reference. A sensing epicardial electrode configuration is disclosed in U.S. Pat. No. 5,476,503, the disclosure of which is incorporated herein by reference.
[0006] In addition to epicardial and transvenous electrodes, subcutaneous electrode systems have also been developed. For example, U.S. Pat. Nos. 5,342,407 and 5,603,732, the disclosures of which are incorporated herein by reference, teach the use of a pulse monitor/generator surgically implanted into the abdomen and subcutaneous electrodes implanted in the thorax. This system is far more complicated to use than current ICD systems using transvenous lead systems together with an active can electrode and therefore it has no practical use. It has in fact never been used because of the surgical difficulty of applying such a device (3 incisions), the impractical abdominal location of the generator and the electrically poor sensing and defibrillation aspects of such a system.
[0007] Recent efforts to improve the efficiency of ICDs have led manufacturers to produce ICDs which are small enough to be implanted in the pectoral region. In addition, advances in circuit design have enabled the housing of the ICD to form a subcutaneous electrode. Some examples of ICDs in which the housing of the ICD serves as an optional additional electrode are described in U.S. Pat. Nos. 5,133,353; 5,261,400; 5,620,477; and 5,658,321, the disclosures of which are incorporated herein by reference.
[0008] ICDs are now an established therapy for the management of life threatening cardiac rhythm disorders, primarily ventricular fibrillation (V-Fib). ICDs are very effective at treating V-Fib, but are therapies that still require significant surgery.
[0009] As ICD therapy becomes more prophylactic in nature and used in progressively less ill individuals, especially children at risk of cardiac arrest, the requirement of ICD therapy to use intravenous catheters and transvenous leads is an impediment to very long term management as most individuals will begin to develop complications related to lead system malfunction sometime in the 5-10 year time frame, often earlier. In addition, chronic transvenous lead systems, their reimplantation and removals, can damage major cardiovascular venous systems and the tricuspid valve, as well as result in life threatening perforations of the great vessels and heart. Consequently, use of transvenous lead systems, despite their many advantages, are not without their chronic patient management limitations in those with life expectancies of >5 years. The problem of lead complications is even greater in children where body growth can substantially alter transvenous lead function and lead to additional cardiovascular problems and revisions. Moreover, transvenous ICD systems also increase cost and require specialized interventional rooms and equipment as well as special skill for insertion. These systems are typically implanted by cardiac electrophysiologists who have had a great deal of extra training.
[0010] In addition to the background related to ICD therapy, the present invention requires a brief understanding of a related therapy, the automatic external defibrillator (AED). AEDs employ the use of cutaneous patch electrodes, rather than implantable lead systems, to effect defibrillation under the direction of a bystander user who treats the patient suffering from V-Fib with a portable device containing the necessary electronics and power supply that allows defibrillation. AEDs can be nearly as effective as an ICD for defibrillation if applied to the victim of ventricular fibrillation promptly, i.e., within 2 to 3 minutes of the onset of the ventricular fibrillation.
[0011] AED therapy has great appeal as a tool for diminishing the risk of death in public venues such as in air flight. However, an AED must be used by another individual, not the person suffering from the potential fatal rhythm. It is more of a public health tool than a patient-specific tool like an ICD. Because >75% of cardiac arrests occur in the home, and over half occur in the bedroom, patients at risk of cardiac arrest are often alone or asleep and can not be helped in time with an AED. Moreover, its success depends to a reasonable degree on an acceptable level of skill and calm by the bystander user.
[0012] What is needed therefore, especially for children and for prophylactic long term use for those at risk of cardiac arrest, is a combination of the two forms of therapy which would provide prompt and near-certain defibrillation, like an ICD, but without the long-term adverse sequelae of a transvenous lead system while simultaneously using most of the simpler and lower cost technology of an AED. What is also needed is a cardioverter/defibrillator that is of simple design and can be comfortably implanted in a patient for many years.
SUMMARY OF THE INVENTION
[0013] A power supply for an implantable cardioverter-defibrillator for subcutaneous positioning between the third rib and the twelfth rib and using a lead system that does not directly contact a patient's heart or reside in the intrathoracic blood vessels and for providing anti-bradycardia pacing energy to the heart, comprising a capacitor subsystem for storing the anti-bradycardia pacing energy for delivery to the patient's heart; and a battery subsystem electrically coupled to the capacitor subsystem for providing the anti-bradycardia pacing energy to the capacitor subsystem.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a better understanding of the invention, reference is now made to the drawings where like numerals represent similar objects throughout the figures where:
[0015] FIG. 1 is a schematic view of a Subcutaneous ICD (S-ICD) of the present invention;
[0016] FIG. 2 is a schematic view of an alternate embodiment of a subcutaneous electrode of the present invention;
[0017] FIG. 3 is a schematic view of an alternate embodiment of a subcutaneous electrode of the present invention;
[0018] FIG. 4 is a schematic view of the S-ICD and lead of FIG. 1 subcutaneously implanted in the thorax of a patient;
[0019] FIG. 5 is a schematic view of the S-ICD and lead of FIG. 2 subcutaneously implanted in an alternate location within the thorax of a patient;
[0020] FIG. 6 is a schematic view of the S-ICD and lead of FIG. 3 subcutaneously implanted in the thorax of a patient;
[0021] FIG. 7 is a schematic view of the method of making a subcutaneous path from the preferred incision and housing implantation point to a termination point for locating a subcutaneous electrode of the present invention;
[0022] FIG. 8 is a schematic view of an introducer set for performing the method of lead insertion of any of the described embodiments;
[0023] FIG. 9 is a schematic view of an alternative S-ICD of the present invention illustrating a lead subcutaneously and serpiginously implanted in the thorax of a patient for use particularly in children;
[0024] FIG. 10 is a schematic view of an alternate embodiment of an S-ICD of the present invention;
[0025] FIG. 11 is a schematic view of the S-ICD of FIG. 10 subcutaneously implanted in the thorax of a patient;
[0026] FIG. 12 is a schematic view of yet a further embodiment where the canister of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient;
[0027] FIG. 13 is a schematic of a different embodiment where the canister of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient;
[0028] FIG. 14 is a schematic view of a Unitary Subcutaneous ICD (US-ICD) of the present invention;
[0029] FIG. 15 is a schematic view of the US-ICD subcutaneously implanted in the thorax of a patient;
[0030] FIG. 16 is a schematic view of the method of making a subcutaneous path from the preferred incision for implanting the US-ICD;
[0031] FIG. 17 is a schematic view of an introducer for performing the method of US-ICD implantation;
[0032] FIG. 18 is an exploded schematic view of an alternate embodiment of the present invention with a plug-in portion that contains operational circuitry and means for generating cardioversion/defibrillation shock waves;
[0033] FIG. 19 is a graph that shows an example of a biphasic waveform for use in anti-bradycardia pacing in an embodiment of the present invention; and
[0034] FIG. 20 is a graph that shows an example of a monophonic waveform for use in anti-bradycardia pacing in an embodiment of the present invention.
DETAILED DESCRIPTION
[0035] Turning now to FIG. 1 , the S-ICD of the present invention is illustrated. The S-ICD consists of an electrically active canister 11 and a subcutaneous electrode 13 attached to the canister. The canister has an electrically active surface 15 that is electrically insulated from the electrode connector block 17 and the canister housing 16 via insulating area 14 . The canister can be similar to numerous electrically active canisters commercially available in that the canister will contain a battery supply, capacitor and operational circuitry. Alternatively, the canister can be thin and elongated to conform to the intercostal space. The circuitry will be able to monitor cardiac rhythms for tachycardia and fibrillation, and if detected, will initiate charging the capacitor and then delivering cardioversion/defibrillation energy through the active surface of the housing and to the subcutaneous electrode. Examples of such circuitry are described in U.S. Pat. Nos. 4,693,253 and 5,105,810, the entire disclosures of which are herein incorporated by reference. The canister circuitry can provide cardioversion/defibrillation energy in different types of waveforms. In one embodiment, a 100 uF biphasic waveform is used of approximately 10-20 ms total duration and with the initial phase containing approximately {fraction (2/3)} of the energy, however, any type of waveform can be utilized such as monophasic, biphasic, multiphasic or alternative waveforms as is known in the art.
[0036] In addition to providing cardioversion/defibrillation energy, the circuitry can also provide transthoracic cardiac pacing energy. The optional circuitry will be able to monitor the heart for bradycardia and/or tachycardia rhythms. Once a bradycardia or tachycardia rhythm is detected, the circuitry can then deliver appropriate pacing energy at appropriate intervals through the active surface and the subcutaneous electrode. Pacing stimuli can be biphasic in one embodiment and similar in pulse amplitude to that used for conventional transthoracic pacing.
[0037] This same circuitry can also be used to deliver low amplitude shocks on the T-wave for induction of ventricular fibrillation for testing S-ICD performance in treating V-Fib as is described in U.S. Pat. No. 5,129,392, the entire disclosure of which is hereby incorporated by reference. Also the circuitry can be provided with rapid induction of ventricular fibrillation or ventricular tachycardia using rapid ventricular pacing. Another optional way for inducing ventricular fibrillation would be to provide a continuous low voltage, i.e., about 3 volts, across the heart during the entire cardiac cycle.
[0038] Another optional aspect of the present invention is that the operational circuitry can detect the presence of atrial fibrillation as described in Olson, W. et al. “Onset And Stability For Ventricular Tachyarrhythmia Detection in an Implantable Cardioverter and Defibrillator,” Computers in Cardiology (1986) pp. 167-170. Detection can be provided via R-R Cycle length instability detection algorithms. Once atrial fibrillation has been detected, the operational circuitry will then provide QRS synchronized atrial defibrillation/cardioversion using the same shock energy and waveshape characteristics used for ventricular defibrillation/cardioversion.
[0039] The sensing circuitry will utilize the electronic signals generated from the heart and will primarily detect QRS waves. In one embodiment, the circuitry will be programmed to detect only ventricular tachycardias or fibrillations. The detection circuitry will utilize in its most direct form, a rate detection algorithm that triggers charging of the capacitor once the ventricular rate exceeds some predetermined level for a fixed period of time: for example, if the ventricular rate exceeds 240 bpm on average for more than 4 seconds. Once the capacitor is charged, a confirmatory rhythm check would ensure that the rate persists for at least another 1 second before discharge. Similarly, termination algorithms could be instituted that ensure that a rhythm less than 240 bpm persisting for at least 4 seconds before the capacitor charge is drained to an internal resistor. Detection, confirmation and termination algorithms as are described above and in the art can be modulated to increase sensitivity and specificity by examining QRS beat-to-beat uniformity, QRS signal frequency content, R-R interval stability data, and signal amplitude characteristics all or part of which can be used to increase or decrease both sensitivity and specificity of S-ICD arrhythmia detection function.
[0040] In addition to use of the sense circuitry for detection of V-Fib or V-Tach by examining the QRS waves, the sense circuitry can check for the presence or the absence of respiration. The respiration rate can be detected by monitoring the impedance across the thorax using subthreshold currents delivered across the active can and the high voltage subcutaneous lead electrode and monitoring the frequency in undulation in the waveform that results from the undulations of transthoracic impedance during the respiratory cycle. If there is no undulation, then the patent is not respiring and this lack of respiration can be used to confirm the QRS findings of cardiac arrest. The same technique can be used to provide information about the respiratory rate or estimate cardiac output as described in U.S. Pat. Nos. 6,095,987; 5,423,326; and 4,450,527, the entire disclosures of which are incorporated herein by reference.
[0041] The canister of the present invention can be made out of titanium alloy or other presently preferred electrically active canister designs. However, it is contemplated that a malleable canister that can conform to the curvature of the patient's chest will be preferred. In this way the patient can have a comfortable canister that conforms to the shape of the patient's rib cage. Examples of conforming canisters are provided in U.S. Pat. No. 5,645,586, the entire disclosure of which is herein incorporated by reference. Therefore, the canister can be made out of numerous materials such as medical grade plastics, metals, and alloys. In the preferred embodiment, the canister is smaller than 60 cc volume having a weight of less than 100 gms for long term wearability, especially in children. The canister and the lead of the S-ICD can also use fractal or wrinkled surfaces to increase surface area to improve defibrillation capability. Because of the primary prevention role of the therapy and the likely need to reach energies over 40 Joules, a feature of one embodiment is that the charge time for the therapy is intentionally left relatively long to allow capacitor charging within the limitations of device size. Examples of small ICD housings are disclosed in U.S. Pat. Nos. 5,597,956 and 5,405,363, the entire disclosures of which are herein incorporated by reference.
[0042] Different subcutaneous electrodes 13 of the present invention are illustrated in FIGS. 1-3 . Turning to FIG. 1 , the lead 21 for the subcutaneous electrode is preferably composed of silicone or polyurethane insulation. The electrode is connected to the canister at its proximal end via connection port 19 which is located on an electrically insulated area 17 of the canister. The electrode illustrated is a composite electrode with three different electrodes attached to the lead. In the embodiment illustrated, an optional anchor segment 52 is attached at the most distal end of the subcutaneous electrode for anchoring the electrode into soft tissue such that the electrode does not dislodge after implantation.
[0043] The most distal electrode on the composite subcutaneous electrode is a coil electrode 27 that is used for delivering the high voltage cardioversion/defibrillation energy across the heart. The coil cardioversion/defibrillation electrode is about 5-10 cm in length. Proximal to the coil electrode are two sense electrodes, a first sense electrode 25 is located proximally to the coil electrode and a second sense electrode 23 is located proximally to the first sense electrode. The sense electrodes are spaced far enough apart to be able to have good QRS detection. This spacing can range from 1 to 10 cm with 4 cm being presently preferred. The electrodes may or may not be circumferential with the preferred embodiment. Having the electrodes non-circumferential and positioned outward, toward the skin surface, is a means to minimize muscle artifact and enhance QRS signal quality. The sensing electrodes are electrically isolated from the cardioversion/defibrillation electrode via insulating areas 29 . Similar types of cardioversion/defibrillation electrodes are currently commercially available in a transvenous configuration. For example, U.S. Pat. No. 5,534,022, the entire disclosure of which is herein incorporated by reference, discloses a composite electrode with a coil cardioversion/defibrillation electrode and sense electrodes. Modifications to this arrangement are contemplated within the scope of the invention. One such modification is illustrated in FIG. 2 where the two sensing electrodes 25 and 23 are non-circumferential sensing electrodes and one is located at the distal end, the other is located proximal thereto with the coil electrode located in between the two sensing electrodes. In this embodiment the sense electrodes are spaced about 6 to about 12 cm apart depending on the length of the coil electrode used. FIG. 3 illustrates yet a further embodiment where the two sensing electrodes are located at the distal end to the composite electrode with the coil electrode located proximally thereto. Other possibilities exist and are contemplated within the present invention. For example, having only one sensing electrode, either proximal or distal to the coil cardioversion/defibrillation electrode with the coil serving as both a sensing electrode and a cardioversion/defibrillation electrode.
[0044] It is also contemplated within the scope of the invention that the sensing of QRS waves (and transthoracic impedance) can be carried out via sense electrodes on the canister housing or in combination with the cardioversion/defibrillation coil electrode and/or the subcutaneous lead sensing electrode(s). In this way, sensing could be performed via the one coil electrode located on the subcutaneous electrode and the active surface on the canister housing. Another possibility would be to have only one sense electrode located on the subcutaneous electrode and the sensing would be performed by that one electrode and either the coil electrode on the subcutaneous electrode or by the active surface of the canister. The use of sensing electrodes on the canister would eliminate the need for sensing electrodes on the subcutaneous electrode. It is also contemplated that the subcutaneous electrode would be provided with at least one sense electrode, the canister with at least one sense electrode, and if multiple sense electrodes are used on either the subcutaneous electrode and/or the canister, that the best QRS wave detection combination will be identified when the S-ICD is implanted and this combination can be selected, activating the best sensing arrangement from all the existing sensing possibilities. Turning again to FIG. 2 , two sensing electrodes 26 and 28 are located on the electrically active surface 15 with electrical insulator rings 30 placed between the sense electrodes and the active surface. These canister sense electrodes could be switched off and electrically insulated during and shortly after defibrillation/cardioversion shock delivery. The canister sense electrodes may also be placed on the electrically inactive surface of the canister. In the embodiment of FIG. 2 , there are actually four sensing electrodes, two on the subcutaneous lead and two on the canister. In the preferred embodiment, the ability to change which electrodes are used for sensing would be a programmable feature of the S-ICD to adapt to changes in the patient physiology and size (in the case of children) over time. The programming could be done via the use of physical switches on the canister, or as presently preferred, via the use of a programming wand or via a wireless connection to program the circuitry within the canister.
[0045] The canister could be employed as either a cathode or an anode of the S-ICD cardioversion/defibrillation system. If the canister is the cathode, then the subcutaneous coil electrode would be the anode. Likewise, if the canister is the anode, then the subcutaneous electrode would be the cathode.
[0046] The active canister housing will provide energy and voltage intermediate to that available with ICDs and most AEDs. The typical maximum voltage necessary for ICDs using most biphasic waveforms is approximately 750 Volts with an associated maximum energy of approximately 40 Joules. The typical maximum voltage necessary for AEDs is approximately 2000-5000 Volts with an associated maximum energy of approximately 200-360 Joules depending upon the model and waveform used. The S-ICD and the US-ICD of the present invention uses maximum voltages in the range of about 50 to about 3500 Volts and is associated with energies of about 0.5 to about 350 Joules. The capacitance of the devices can range from about 25 to about 200 micro farads.
[0047] In another embodiment, the S-ICD and US-ICD devices provide energy with a pulse width of approximately one millisecond to approximately 40 milliseconds. The devices can provide pacing current of approximately one milliamp to approximately 250 milliamps.
[0048] The sense circuitry contained within the canister is highly sensitive and specific for the presence or absence of life threatening ventricular arrhythmias. Features of the detection algorithm are programmable and the algorithm is focused on the detection of V-Fib and high rate V-Tach (>240 bpm). Although the S-ICD of the present invention may rarely be used for an actual life-threatening event, the simplicity of design and implementation allows it to be employed in large populations of patients at modest risk with modest cost by non-cardiac electrophysiologists. Consequently, the S-ICD of the present invention focuses mostly on the detection and therapy of the most malignant rhythm disorders. As part of the detection algorithm's applicability to children, the upper rate range is programmable upward for use in children, known to have rapid supraventricular tachycardias and more rapid ventricular fibrillation. Energy levels also are programmable downward in order to allow treatment of neonates and infants.
[0049] Turning now to FIG. 4 , the optimal subcutaneous placement of the S-ICD of the present invention is illustrated. As would be evidence to a person skilled in the art, the actual location of the S-ICD is in a subcutaneous space that is developed during the implantation process. The heart is not exposed during this process and the heart is schematically illustrated in the figures only for help in understanding where the canister and coil electrode are three dimensionally located in the left mid-clavicular line approximately at the level of the inframammary crease at approximately the 5th rib. The lead 21 of the subcutaneous electrode traverses in a subcutaneous path around the thorax terminating with its distal electrode end at the posterior axillary line ideally just lateral to the left scapula. This way the canister and subcutaneous cardioversion/defibrillation electrode provide a reasonably good pathway for current delivery to the majority of the ventricular myocardium.
[0050] FIG. 5 illustrates a different placement of the present invention. The S-ICD canister with the active housing is located in the left posterior axillary line approximately lateral to the tip of the inferior portion of the scapula. This location is especially useful in children. The lead 21 of the subcutaneous electrode traverses in a subcutaneous path around the thorax terminating with its distal electrode end at the anterior precordial region, ideally in the inframammary crease. FIG. 6 illustrates the embodiment of FIG. 1 subcutaneously implanted in the thorax with the proximal sense electrodes 23 and 25 located at approximately the left axillary line with the cardioversion/defibrillation electrode just lateral to the tip of the inferior portion of the scapula.
[0051] FIG. 7 schematically illustrates the method for implanting the S-ICD of the present invention. An incision 31 is made in the left anterior axillary line approximately at the level of the cardiac apex. This incision location is distinct from that chosen for S-ICD placement and is selected specifically to allow both canister location more medially in the left inframammary crease and lead positioning more posteriorly via the introducer set (described below) around to the left posterior axillary line lateral to the left scapula. That said, the incision can be anywhere on the thorax deemed reasonable by the implanting physician although in the preferred embodiment, the S-ICD of the present invention will be applied in this region. A subcutaneous pathway 33 is then created medially to the inframammary crease for the canister and posteriorly to the left posterior axillary line lateral to the left scapula for the lead.
[0052] The S-ICD canister 11 is then placed subcutaneously at the location of the incision or medially at the subcutaneous region at the left inframammary crease. The subcutaneous electrode 13 is placed with a specially designed curved introducer set 40 (see FIG. 8 ). The introducer set comprises a curved trocar 42 and a stiff curved peel away sheath 44 . The peel away sheath is curved to allow for placement around the rib cage of the patient in the subcutaneous space created by the trocar. The sheath has to be stiff enough to allow for the placement of the electrodes without the sheath collapsing or bending. Preferably the sheath is made out of a biocompatible plastic material and is perforated along its axial length to allow for it to split apart into two sections. The trocar has a proximal handle 41 and a curved shaft 43 . The distal end 45 of the trocar is tapered to allow for dissection of a subcutaneous path 33 in the patient. Preferably, the trocar is cannulated having a central Lumen 46 and terminating in an opening 48 at the distal end. Local anesthetic such as lidocaine can be delivered, if necessary, through the lumen or through a curved and elongated needle designed to anesthetize the path to be used for trocar insertion should general anesthesia not be employed. The curved peel away sheath 44 has a proximal pull tab 49 for breaking the sheath into two halves along its axial shaft 47 . The sheath is placed over a guidewire inserted through the trocar after the subcutaneous path has been created. The subcutaneous pathway is then developed until it terminates subcutaneously at a location that, if a straight line were drawn from the canister location to the path termination point the line would intersect a substantial portion of the left ventricular mass of the patient. The guidewire is then removed leaving the peel away sheath. The subcutaneous lead system is then inserted through the sheath until it is in the proper location. Once the subcutaneous lead system is in the proper location, the sheath is split in half using the pull tab 49 and removed. If more than one subcutaneous electrode is being used, a new curved peel away sheath can be used for each subcutaneous electrode.
[0053] The S-ICD will have prophylactic use in adults where chronic transvenous/epicardial ICD lead systems pose excessive risk or have already resulted in difficulty, such as sepsis or lead fractures. It is also contemplated that a major use of the S-ICD system of the present invention will be for prophylactic use in children who are at risk for having fatal arrhythmias, where chronic transvenous lead systems pose significant management problems. Additionally, with the use of standard transvenous ICDs in children, problems develop during patient growth in that the lead system does not accommodate the growth. FIG. 9 illustrates the placement of the S-ICD subcutaneous lead system such that the problem that growth presents to the lead system is overcome. The distal end of the subcutaneous electrode is placed in the same location as described above providing a good location for the coil cardioversion/defibrillation electrode 27 and the sensing electrodes 23 and 25 . The insulated lead 21 , however, is no longer placed in a taut configuration. Instead, the lead is serpiginously placed with a specially designed introducer trocar and sheath such that it has numerous waves or bends. As the child grows, the waves or bends will straighten out lengthening the lead system while maintaining proper electrode placement. Although it is expected that fibrous scarring especially around the defibrillation coil will help anchor it into position to maintain its posterior position during growth, a lead system with a distal tine or screw electrode anchoring system 52 can also be incorporated into the distal tip of the lead to facilitate lead stability (see FIG. 1 ). Other anchoring systems can also be used such as hooks, sutures, or the like.
[0054] FIGS. 10 and 11 illustrate another embodiment of the present S-ICD invention. In this embodiment there are two subcutaneous electrodes 13 and 13 ′ of opposite polarity to the canister. The additional subcutaneous electrode 13 ′ is essentially identical to the previously described electrode. In this embodiment the cardioversion/defibrillation energy is delivered between the active surface of the canister and the two coil electrodes 27 and 27 ′. Additionally, provided in the canister is means for selecting the optimum sensing arrangement between the four sense electrodes 23 , 23 ′, 25 , and 25 ′. The two electrodes are subcutaneously placed on the same side of the heart. As illustrated in FIG. 6 , one subcutaneous electrode 13 is placed inferiorly and the other electrode 13 ′ is placed superiorly. It is also contemplated with this dual subcutaneous electrode system that the canister and one subcutaneous electrode are the same polarity and the other subcutaneous electrode is the opposite polarity.
[0055] Turning now to FIGS. 12 and 13 , further embodiments are illustrated where the canister 11 of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient. The canister is long, thin, and curved to conform to the shape of the patient's rib. In the embodiment illustrated in FIG. 12 , the canister has a diameter ranging from about 0.5 cm to about 2 cm without 1 cm being presently preferred. Alternatively, instead of having a circular cross sectional area, the canister could have a rectangular or square cross sectional area as illustrated in FIG. 13 without falling outside of the scope of the present invention. The length of the canister can vary depending on the size of the patient's thorax. In an embodiment, the canister is about 5 cm to about 40 cm long. The canister is curved to conform to the curvature of the ribs of the thorax. The radius of the curvature will vary depending on the size of the patient, with smaller radiuses for smaller patients and larger radiuses for larger patients. The radius of the curvature can range from about 5 cm to about 35 cm depending on the size of the patient. Additionally, the radius of the curvature need not be uniform throughout the canister such that it can be shaped closer to the shape of the ribs. The canister has an active surface, 15 that is located on the interior (concave) portion of the curvature and an inactive surface 16 that is located on the exterior (convex) portion of the curvature. The leads of these embodiments, which are not illustrated except for the attachment port 19 and the proximal end of the lead 21 , can be any of the leads previously described above, with the lead illustrated in FIG. 1 being presently preferred.
[0056] The circuitry of this canister is similar to the circuitry described above. Additionally, the canister can optionally have at least one sense electrode located on either the active surface of the inactive surface and the circuitry within the canister can be programmable as described above to allow for the selection of the best sense electrodes. It is presently preferred that the canister have two sense electrodes 26 and 28 located on the inactive surface of the canisters as illustrated, where the electrodes are spaced from about 1 to about 10 cm apart with a spacing of about 3 cm being presently preferred. However, the sense electrodes can be located on the active surface as described above.
[0057] It is envisioned that the embodiment of FIG. 12 will be subcutaneously implanted adjacent and parallel to the left anterior 5th rib, either between the 4th and 5th ribs or between the 5th and 6th ribs. However other locations can be used.
[0058] Another component of the S-ICD of the present invention is a cutaneous test electrode system designed to simulate the subcutaneous high voltage shock electrode system as well as the QRS cardiac rhythm detection system. This test electrode system is comprised of a cutaneous patch electrode of similar surface area and impedance to that of the S-ICD canister itself together with a cutaneous strip electrode comprising a defibrillation strip as well as two button electrodes for sensing of the QRS. Several cutaneous strip electrodes are available to allow for testing various bipole spacings to optimize signal detection comparable to the implantable system.
[0059] FIGS. 14 to 18 depict particular US-ICD embodiments of the present invention. The various sensing, shocking and pacing circuitry, described in detail above with respect to the S-ICD embodiments, may additionally be incorporated into the following US-ICD embodiments. Furthermore, particular aspects of any individual S-ICD embodiment discussed above may be incorporated, in whole or in part, into the US-ICD embodiments depicted in the following figures.
[0060] Turning now to FIG. 14 , the US-ICD of the present invention is illustrated. The US-ICD consists of a curved housing 1211 with a first and second end. The first end 1413 is thicker than the second end 1215 . This thicker area houses a battery supply, capacitor and operational circuitry for the US-ICD. The circuitry will be able to monitor cardiac rhythms for tachycardia and fibrillation, and if detected, will initiate charging the capacitor and then delivering cardioversion/defibrillation energy through the two cardioversion/defibrillating electrodes 1417 and 1219 located on the outer surface of the two ends of the housing. The circuitry can provide cardioversion/defibrillation energy in different types of waveforms. In one embodiment, a 100 uF biphasic waveform is used of approximately 10-20 ms total duration and with the initial phase containing approximately {fraction (2/3)} of the energy, however, any type of waveform can be utilized such as monophasic, biphasic, multiphasic or alternative waveforms as is known in the art.
[0061] The housing of the present invention can be made out of titanium alloy or other presently preferred ICD designs. It is contemplated that the housing is also made out of biocompatible plastic materials that electronically insulate the electrodes from each other. However, it is contemplated that a malleable canister that can conform to the curvature of the patient's chest will be preferred. In this way the patient can have a comfortable canister that conforms to the unique shape of the patient's rib cage. Examples of conforming ICD housings are provided in U.S. Pat. No. 5,645,586, the entire disclosure of which is herein incorporated by reference. In the preferred embodiment, the housing is curved in the shape of a 5 th rib of a person. Because there are many different sizes of people, the housing will come in different incremental sizes to allow a good match between the size of the rib cage and the size of the US-ICD. The length of the US-ICD will range from about 15 to about 50 cm. Because of the primary preventative role of the therapy and the need to reach energies over 40 Joules, a feature of the preferred embodiment is that the charge time for the therapy, intentionally be relatively long to allow capacitor charging within the limitations of device size.
[0062] The thick end of the housing is currently needed to allow for the placement of the battery supply, operational circuitry, and capacitors. It is contemplated that the thick end will be about 0.5 cm to about 2 cm wide with about 1 cm being presently preferred. As microtechnology advances, the thickness of the housing will become smaller.
[0063] The two cardioversion/defibrillation electrodes on the housing are used for delivering the high voltage cardioversion/defibrillation energy across the heart. In the preferred embodiment, the cardioversion/defibrillation electrodes are coil electrodes, however, other cardioversion/defibrillation electrodes could be used such as having electrically isolated active surfaces or platinum alloy electrodes. The coil cardioversion/defibrillation electrodes are about 5-10 cm in length. Located on the housing between the two cardioversion/defibrillation electrodes are two sense electrodes 1425 and 1427 . The sense electrodes are spaced far enough apart to be able to have good QRS detection. This spacing can range from 1 to 10 cm with 4 cm being presently preferred. The electrodes may or may not be circumferential with the preferred embodiment. Having the electrodes non-circumferential and positioned outward, toward the skin surface, is a means to minimize muscle artifact and enhance QRS signal quality. The sensing electrodes are electrically isolated from the cardioversion/defibrillation electrode via insulating areas 1423 . Analogous types of cardioversion/defibrillation electrodes are currently commercially available in a transvenous configuration. For example, U.S. Pat. No. 5,534,022, the entire disclosure of which is herein incorporated by reference, discloses a composite electrode with a coil cardioversion/defibrillation electrode and sense electrodes. Modifications to this arrangement are contemplated within the scope of the invention. One such modification is to have the sense electrodes at the two ends of the housing and have the cardioversion/defibrillation electrodes located in between the sense electrodes. Another modification is to have three or more sense electrodes spaced throughout the housing and allow for the selection of the two best sensing electrodes. If three or more sensing electrodes are used, then the ability to change which electrodes are used for sensing would be a programmable feature of the US-ICD to adapt to changes in the patient physiology and size over time. The programming could be done via the use of physical switches on the canister, or as presently preferred, via the use of a programming wand or via a wireless connection to program the circuitry within the canister.
[0064] Turning now to FIG. 15 , the optimal subcutaneous placement of the US-ICD of the present invention is illustrated. As would be evident to a person skilled in the art, the actual location of the US-ICD is in a subcutaneous space that is developed during the implantation process. The heart is not exposed during this process and the heart is schematically illustrated in the figures only for help in understanding where the device and its various electrodes are three dimensionally located in the thorax of the patient. The US-ICD is located between the left mid-clavicular line approximately at the level of the inframammary crease at approximately the 5 th rib and the posterior axillary line, ideally just lateral to the left scapula. This way the US-ICD provides a reasonably good pathway for current delivery to the majority of the ventricular myocardium.
[0065] FIG. 16 schematically illustrates the method for implanting the US-ICD of the present invention. An incision 1631 is made in the left anterior axillary line approximately at the level of the cardiac apex. A subcutaneous pathway is then created that extends posteriorly to allow placement of the US-ICD. The incision can be anywhere on the thorax deemed reasonable by the implanting physician although in the preferred embodiment, the US-ICD of the present invention will be applied in this region. The subcutaneous pathway is created medially to the inframammary crease and extends posteriorly to the left posterior axillary line. The pathway is developed with a specially designed curved introducer 1742 (see FIG. 17 ). The trocar has a proximal handle 1641 and a curved shaft 1643 . The distal end 1745 of the trocar is tapered to allow for dissection of a subcutaneous path in the patient. Preferably, the trocar is cannulated having a central lumen 1746 and terminating in an opening 1748 at the distal end. Local anesthetic such as lidocaine can be delivered, if necessary, through the lumen or through a curved and elongated needle designed to anesthetize the path to be used for trocar insertion should general anesthesia not be employed. Once the subcutaneous pathway is developed, the US-ICD is implanted in the subcutaneous space, the skin incision is closed using standard techniques.
[0066] As described previously, the US-ICDs of the present invention vary in length and curvature. The US-ICDs are provided in incremental sizes for subcutaneous implantation in different sized patients. Turning now to FIG. 18 , a different embodiment is schematically illustrated in exploded view which provides different sized US-ICDs that are easier to manufacture. The different sized US-ICDs will all have the same sized and shaped thick end 1413 . The thick end is hollow inside allowing for the insertion of a core operational member 1853 . The core member comprises a housing 1857 which contains the battery supply, capacitor and operational circuitry for the US-ICD. The proximal end of the core member has a plurality of electronic plug connectors. Plug connectors 1861 and 1863 are electronically connected to the sense electrodes via pressure fit connectors (not illustrated) inside the thick end which are standard in the art. Plug connectors 1865 and 1867 are also electronically connected to the cardioverter/defibrillator electrodes via pressure fit connectors inside the thick end. The distal end of the core member comprises an end cap 1855 , and a ribbed fitting 1859 which creates a water-tight seal when the core member is inserted into opening 1851 of the thick end of the US-ICD.
[0067] The S-ICD and US-ICD, in alternative embodiments, have the ability to detect and treat atrial rhythm disorders, including atrial fibrillation. The S-ICD and US-ICD have two or more electrodes that provide a far-field view of cardiac electrical activity that includes the ability to record the P-wave of the electrocardiogram as well as the QRS. One can detect the onset and offset of atrial fibrillation by referencing to the P-wave recorded during normal sinus rhythm and monitoring for its change in rate, morphology, amplitude and frequency content. For example, a well-defined P-wave that abruptly disappeared and was replaced by a low-amplitude, variable morphology signal would be a strong indication of the absence of sinus rhythm and the onset of atrial fibrillation. In an alternative embodiment of a detection algorithm, the ventricular detection rate could be monitored for stability of the R-R coupling interval. In the examination of the R-R interval sequence, atrial fibrillation can be recognized by providing a near constant irregularly irregular coupling interval on a beat-by-beat basis. An R-R interval plot during AF appears “cloudlike” in appearance when several hundred or thousands of R-R intervals are plotted over time when compared to sinus rhythm or other supraventricular arrhythmias. Moreover, a distinguishing feature compared to other rhythms that are irregularly irregular, is that the QRS morphology is similar on a beat-by-beat basis despite the irregularity in the R-R coupling interval. This is a distinguishing feature of atrial fibrillation compared to ventricular fibrillation where the QRS morphology varies on a beat-by-beat basis. In yet another embodiment, atrial fibrillation may be detected by seeking to compare the timing and amplitude relationship of the detected P-wave of the electrocardiogram to the detected QRS(R-wave) of the electrocardiogram. Normal sinus rhythm has a fixed relationship that can be placed into a template matching algorithm that can be used as a reference point should the relationship change.
[0068] In other aspects of the atrial fibrillation detection process, one may include alternative electrodes that may be brought to bear in the S-ICD or US-ICD systems either by placing them in the detection algorithm circuitry through a programming maneuver or by manually adding such additional electrode systems to the S-ICD or US-ICD at the time of implant or at the time of follow-up evaluation. One may also use electrodes for the detection of atrial fibrillation that may or may not also be used for the detection of ventricular arrhythmias given the different anatomic locations of the atria and ventricles with respect to the S-ICD or US-ICD housing and surgical implant sites.
[0069] Once atrial fibrillation is detected, the arrhythmia can be treated by delivery of a synchronized shock using energy levels up to the maximum output of the device therapy for terminating atrial fibrillation or for other supraventricular arrhythmias. The S-ICD or US-ICD electrode system can be used to treat both atrial and ventricular arrhythmias not only with shock therapy but also with pacing therapy. In a further embodiment of the treatment of atrial fibrillation or other atrial arrhythmias, one may be able to use different electrode systems than what is used to treat ventricular arrhythmias. Another embodiment would be to allow for different types of therapies (amplitude, waveform, capacitance, etc.) for atrial arrhythmias compared to ventricular arrhythmias.
[0070] The core member of the different sized and shaped US-ICD will all be the same size and shape. That way, during an implantation procedure, multiple sized US-ICDs can be available for implantation, each one without a core member. Once the implantation procedure is being performed, then the correct sized US-ICD can be selected and the core member can be inserted into the US-ICD and then programmed as described above. Another advantage of this configuration is when the battery within the core member needs replacing it can be done without removing the entire US-ICD.
[0071] Post-shock bradycardia is a common after-effect of shocking the heart for cardioversion/defibrillation therapy. Symptoms related to low blood pressure may result from post-shock bradycardia whenever the heart rate falls below approximately 30 to approximately 50 beats per minute. Accordingly, it is often desirable to provide anti-bradycardia pacing to correct the symptoms resulting from bradycardia.
[0072] To ensure adequate pacing capture of the heart through a subcutaneous only lead system, pacing therapy can be considerably enhanced (i.e., require less energy and voltage) by using either a monophasic or a biphasic waveform for pacing.
[0073] FIG. 19 is a graph that shows an embodiment of the example of a biphasic waveform for use in anti-bradycardia pacing applications in subcutaneous implantable cardioverter-defibrillators (“S-ICD”) in an embodiment of the present invention. As shown in FIG. 19 , the biphasic waveform is plotted as a function of current versus time.
[0074] In an embodiment, the biphasic waveform 1902 comprises a positive portion 1904 , a negative portion 1906 and a transition portion 1908 . In an embodiment, both the positive portion 1904 and the negative portion 1906 are substantially rectangular in shape. The positive portion 1904 of the biphasic waveform 1902 comprises an initial positive current 1910 , a positive fixed current 1912 and a final positive current 1914 . The negative portion 1906 of the biphasic waveform 1902 comprises an initial negative current 1916 , a negative fixed current 1918 and a final negative current 1920 . In an embodiment, the polarities of the biphasic waveform 1902 can be reversed such that the negative portion 1906 precedes the positive portion 1904 in time.
[0075] As shown in FIG. 19 , the biphasic waveform 1902 is initially at zero current. Upon commencement of the anti-bradycardia pacing, a current of positive polarity is provided and the biphasic waveform 1902 rises to the initial positive current 1910 . Next, the current of the biphasic waveform 1902 remains at a constant level along the positive fixed current 1912 . The positive portion 1904 of the biphasic waveform 1902 is then truncated and a negative current is provided. The biphasic waveform 1902 then undergoes a relatively short transition portion 1908 where the current is approximately zero. Next, the biphasic waveform 1902 is increased (in absolute value) in the opposite (negative) polarity to the initial negative current 1916 . After reaching its maximum negative current (in absolute value), the current of the biphasic waveform 1902 remains at a constant level along the negative fixed current 1918 . After the negative portion 1906 of the biphasic waveform 1902 is truncated at the final negative current 1914 , the biphasic waveform 1902 returns to zero.
[0076] The total amount of time that the biphasic waveform 1902 comprises is known as the “pulse width.” In an embodiment, the pulse width of the biphasic waveform can range from approximately 1 millisecond to approximately 40 milliseconds. The total amount of energy delivered is a function of the pulse width and the absolute value of the current.
[0077] An example of one embodiment of the biphasic waveform 1902 will now be described. In this embodiment, the amplitude of the initial positive current 1910 can range from approximately one to approximately 250 milliamps. Similarly, the amplitude of the initial negative current 1916 can range from approximately one to approximately 250 milliamps.
[0078] In the example, the pulse width of the biphasic waveform 1902 can range from approximately 1 millisecond to approximately 40 milliseconds. In addition, the implantable cardioverter-defibrillator employs biphasic anti-bradycardia pacing at rates of approximately 20 to approximately 120 stimuli/minute for severe bradycardia episodes although programming of higher pacing rates up to 120 stimuli/minute is also possible.
[0079] FIG. 20 is a graph that shows an embodiment of the example of a monophasic waveform for use in anti-bradycardia pacing applications in subcutaneous implantable cardioverter-defibrillators (“S-ICD”) in an embodiment of the present invention. As shown in FIG. 20 , the monophasic waveform is plotted as a function of current versus time.
[0080] In an embodiment, the monophasic waveform 2002 comprises an initial positive current 2004 , a positive fixed current 2006 and a final positive current 2008 . In an embodiment, the monophasic waveform 2002 is substantially rectangular in shape. In an embodiment, the polarities of the monophasic waveform 2002 can be reversed such that the waveform 2002 is negative in polarity.
[0081] As shown in FIG. 20 , the monophasic waveform 2002 is initially at zero current. Upon commencement of the anti-bradycardia pacing, a current of positive polarity is provided and the monophasic waveform 2002 rises to the initial positive current 2004 . Next, the current of the monophasic waveform 2002 remains at a constant level along the positive fixed current 1906 . The monophasic waveform 2002 is then truncated.
[0082] The total amount of time that the monophasic waveform 2002 comprises is known as the “pulse width.” In an embodiment, the pulse width of the monophasic waveform can range from approximately 1 millisecond to approximately 40 milliseconds. The total amount of energy delivered is a function of the pulse width and the absolute value of the current.
[0083] An example of one embodiment of the monophasic waveform 2002 will now be described. In this embodiment, the amplitude of the initial positive current 2004 can range from approximately one to approximately 250 milliamps.
[0084] In the example, the pulse width of the monophasic waveform 2002 can range from approximately 1 millisecond to approximately 40 milliseconds. In addition, the implantable cardioverter-defibrillator employs monophasic anti-bradycardia pacing at rates of approximately 20 to approximately 120 stimuli/minute for severe bradycardia episodes although programming of higher pacing rates up to 120 stimuli/minute is also possible. In order to maintain these rates, in one embodiment of the invention, the power supply continues to operate to maintain a sufficient voltage to deliver a constant current.
[0085] Although it possible for the present invention to provide standard VVI pacing at predetermined or preprogrammed rates, one embodiment provides anti-bradycardia pacing only for bradycardia or post-shock bradycardia. To avoid frequent anti-bradycardia pacing at 50 stimuli/minute but to provide this rate in case of emergencies, a hysteresis detection trigger can be employed at lower rates, typically in the range of approximately 20 to approximately 40 stimuli/minute. For example, a default setting may be set at approximately 20 stimuli/minute (i.e., the equivalent of a 3 second pause), and the invention providing VVI pacing at a rate of approximately 50 stimuli/minute only when such a pause occurs. In another embodiment, the invention can provide physiologic pacing in a VVIR mode of operation in response to a certain activity, respiration, pressure or oxygenation sensor.
[0086] The S-ICD and US-ICD devices and methods of the present invention may be embodied in other specific forms without departing from the teachings or essential characteristics of the invention. The described embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore to be embraced therein. | A power supply for an implantable cardioverter-defibrillator for subcutaneous positioning between the third rib and the twelfth rib and using a lead system that does not directly contact a patient's heart or reside in the intrathoracic blood vessels and for providing anti-bradycardia pacing energy to the heart, comprising a capacitor subsystem for storing the anti-bradycardia pacing energy for delivery to the patient's heart; and a battery subsystem electrically coupled to the capacitor subsystem for providing the anti-bradycardia pacing energy to the capacitor subsystem. | 0 |
PRIORITY CLAIM
[0001] This application is a continuation of and claims the benefit of U.S. patent application Ser. No. 09/963,922, filed Sep. 26, 2001, the entire contents of which is incorporated herein.
CROSS REFERENCE TO RELATING APPLICATIONS
[0002] The present invention relates to the following co-pending, commonly owned, U.S. patent applications “GAMING DEVICE HAVING DIFFERENT SETS OF PRIMARY AND SECONDARY REEL SYMBOLS,” Ser. No. 10/098,691; Attorney Docket No. 0112300-994; “GAMING DEVICE HAVING INDEPENDENT REEL COLUMNS,” Ser. No. 10/165,260, Attorney Docket No. 0112300-1016; : “GAMING DEVICE HAVING INDEPENDENT BONUS REELS,” Ser. No. 10/678,512, Attorney Docket No. 0112300-1795; and “GAMING DEVICE HAVING A REPLICATING DISPLAY THAT PROVIDES WINNING PAYLINE INFORMATION”, Ser. No. 10/715,638, Attorney Docket No. 0112300-1799.
COPYRIGHT NOTICE
[0003] A portion of the disclosure of this patent document contains or may contain material which is subject to copyright protection. The copyright owner has no objection to the photocopy reproduction by anyone of the patent document or the patent disclosure in exactly the form it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
DESCRIPTION
[0004] The present invention relates in general to a gaming device having a plurality of identical sets of reels with gaming symbols, and more particularly to a slot gaming device which provides a base or primary game with a plurality of simultaneously playable identical sets of reels with gaming symbols.
BACKGROUND OF THE INVENTION
[0005] Gaming machines currently exist with mechanical or video reels having symbols thereon. In general, a player is awarded one or more credits in a slot gaming machine when one or more randomly generated symbols or combination of symbols appear on a payline. Known gaming devices also awards credits for combinations of scattered symbols.
[0006] To increase player enjoyment and excitement provided by gaming machines, gaming device manufacturers constantly strive to provide players with new types of gaming machines that attract players and keep players entertained. One proven way manufacturers use to make their gaming machines more popular is to increase the number and variety of winning combinations and provide more opportunities for the player to win. Providing more variety and opportunities holds the player's interest for a longer time and also enables the manufacturer to have a wider range of payouts for the winning combinations.
[0007] To increase the number and variety of winning combinations, manufacturers have increased the number of paylines. Paylines are predetermined arrays in the set of reels where the gaming machine evaluates whether a predetermined combination of symbols occurred. A payline may consist of any number or configurations of positions of gaming symbols. For example, a payline in a set of reels can consist of a horizontal line of gaming symbols along the reels, or a diagonal line of gaming symbols along the reels, or a line overlapping several rows along the reels. It is well known to provide gaming machines with multiple paylines.
[0008] It should also be appreciated that gaming machines have become rather complex in comparison to the conventional three reel machines. Currently, many slot machines have a display with a set of five reels with three gaming symbols visible on each reel. This results in a visible set of gaming symbols in a three by five configuration. The majority of five reel slot machines have nine paylines, although twelve, fifteen, twenty and twenty-five payline games are becoming more common. Slot machines may also utilize more than five reels and/or more than three visible gaming symbols on each reel, such as a ten reel configuration with ten visible gaming symbols on each reel. Such a slot machine may have a large number of potential paylines on a singular set of reels. With the increased complexity of the number and the positioning of the paylines on a singular set of reels, it becomes increasingly unwieldy for the gaming software to evaluate a winning combination or combinations of gaming symbols. At some point, adding variety yields diminished returns because of increased complexity. Multiple winning combinations may also become too complex for the player (i.e., a player may win after a given spin of the reels and find it difficult to determine how, where or why the player has won).
[0009] Current gaming machines also provide secondary or bonus games in addition to primary games. These secondary or bonus games are generally different from the primary game. The secondary or bonus games are played separately from the primary game. For instance, secondary or bonus games may be evaluated with a different sets of predetermined combinations of the gaming symbols and/or different paylines. Bonus games may also be completely different games.
[0010] One known game which provides a variety of winning combinations which are readily understandable to players is International Game Technology's TOTEM POLE™ game which enables a player to play three different games on one gaming machine at the same time. The TOTEM POLE™ game has the following three separate games on three different sets of reels: RED, WHITE & BLUE™ game; DOUBLE DIAMOND™ game; and FIVE TIMES PAY™ game. The RED, WHITE & BLUE™ game pays a jackpot when the red “7” symbol, the white “7” symbol and the blue “7” symbol appear on a payline. The DOUBLE DIAMOND™ game utilizes the DOUBLE DIAMOND™ symbol as a wildcard. If one DOUBLE DIAMOND™ symbol lands on a payline in a winning combination, the game pays double the original award associated with the winning combination. If two DOUBLE DIAMOND™ symbols lands on a payline in a winning combination, the game pays four times the original award associated with the winning combination. The FIVE TIMES PAY™ game pays five times the original award of a winning combination when the FIVE TIMES PAY™ symbol appears in the combination on a payline. If two FIVE TIMES PAY™ symbols appear on a payline in a winning combination, the game pays twenty-five times the original award associated with the winning combination. If the FIVE TIMES PAY™ symbol appears in each position on the payline and the player played the maximum bet, the player wins the highest award associated with that game.
[0011] The TOTEM POLE™ game also includes a jackpot. If the TOTEM POLE™ symbol appears on each reel on each of the three paylines (i.e., the payline in each game) the player wins a jackpot if the player bets the maximum bet of six coins. The game thus has three paylines. The player may bet two coins on each payline. This game also allows the player to bet (a) one or two coins on the payline in the first game; (b) two coins on the payline in the first game and one or two coins on the payline in the second game; and (c) two coins on the payline in the first game, two coins on the payline in the second game, and one or two coins on the payline in the third game.
[0012] To increase player enjoyment and excitement, it is desirable to provide new gaming machines with a base or primary game whereby players can easily recognize winning combinations of gaming symbols on a multitude of paylines. It is also desirable to reduce the complexity of gaming software needed to evaluate winning combinations on multiple paylines.
SUMMARY OF THE INVENTION
[0013] The present invention provides a gaming device having a plurality of identical sets of reels for a base or primary game wherein the player places wagers on a number of paylines on the multiple sets of reels. The gaming device simultaneously activates or spins the reels in each of the plurality of sets of reels. The gaming device evaluates each payline the player has wagered on for a predetermined gaming symbol or combination of gaming symbols and awards the player credits (if any) depending on the amount wagered and the value associated with that particular winning gaming symbol or combination of gaming symbols on each set of reels. Because the sets of reels are identical, the gaming software is less complex and the player can readily determine how, where and why the player has won.
[0014] One embodiment of the present invention provides a gaming device wherein the player plays a video slot gaming machine. The gaming device video screen displays three identical sets of virtual gaming reels. Each set of reels consists of five virtual gaming reels with three virtual visible gaming symbols displayed on each reel. This embodiment of the invention has nine paylines associated with each set of virtual gaming reels. Thus, in one standard game, there are twenty-seven total paylines available to a player.
[0015] In this embodiment of the invention, the player chooses the number and location of the paylines to wager on. The player picks from a plurality of paylines from the three identical sets of virtual gaming reels in a conventional manner. The player also chooses the number of credits to wager on each payline in a conventional manner. Upon initiation of game play, all three sets of virtual gaming reels simultaneously spin. In one embodiment, this may appear to the player that the player is playing three separate slot gaming devices. All three sets of virtual gaming reels display randomly determined gaming symbols. The gaming device evaluates each payline the player has wagered on for a predetermined winning gaming symbol or winning combinations of gaming symbols. The gaming device software thus evaluates nine paylines for each set of gaming reels and repeats the evaluation for each set of reels. The gaming device software thus evaluates a total of twenty-seven paylines in this embodiment of the present invention. The player is awarded credits utilizing the value associated with the predetermined symbols or combinations of gaming symbols and the number of winning symbols or combinations on the paylines which the player has wagered on and the amount wagered by the player.
[0016] In one embodiment, each coin bet triggers at least one payline. For example, one coin can be bet on all nine paylines in the first set of reels. If an additional coin is wagered, the next coin bet is placed on the tenth line or the first line in the second set of reels. Similarly, a bet of the nineteenth coin is a bet on a payline in the third set of reels. Alternatively, the player can initiate a wager on each payline individually. In other words, the player can bet any amount of coins on any of the twenty-seven paylines, up to a certain maximum number of coins on each payline. Thus, in one embodiment, the player may wager five coins on each of the twenty-seven paylines or 135 coins for the game.
[0017] It is therefore an advantage of the present invention to provide a gaming device having multiple identical sets of reels.
[0018] A further advantage of the present invention to provide a gaming device which enables a player to play multiple paylines in a primary slot game where the player can distinguish predetermined winning combinations in easily recognized paylines.
[0019] Other features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like numerals refer to like parts, elements, components, steps and processes.
BRIEF DESCRIPTION OF THE FIGURES
[0020] FIGS. 1A and 1B are front plan views of alternative embodiments of the gaming device of the present invention;
[0021] FIG. 2 is a schematic block diagram of the electronic configuration of one embodiment of the gaming device of the present invention;
[0022] FIGS. 3A and 3B are flow diagrams of different embodiments of standard gaming schemes of the present invention; and
[0023] FIG. 4 is a front elevational view of an alternative display for the gaming device of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Gaming Device and Electronics
[0024] Referring now to the drawings, and in particular to FIGS. 1A and 1B , gaming device 10 a and gaming device 10 b illustrate two possible cabinet styles and display arrangements of the present invention and are collectively referred to herein as gaming device 10 . The present invention includes the base or primary game (described below) being multiple identical games coordinated simultaneously during ordinary game play. The gaming device 10 is a slot machine having the controls, displays and features of a conventional slot machine, wherein the player operates the gaming device while standing or sitting. Gaming device 10 also includes being a pub-style or tabletop game (not shown), which a player operates while sitting.
[0025] The gaming device of the present invention may also include any bonus triggering events, bonus games as well as any progressive game coordinating with the base game. The symbols and indicia used for any of the base, bonus and progressive games include mechanical, electrical or video symbols and indicia.
[0026] The gaming device 10 includes monetary input devices. FIGS. 1A and 1B illustrate a coin slot 12 for coins or tokens and/or a payment acceptor 14 for paper money. The payment acceptor 14 also includes other devices for accepting payment, such as readers or validators for credit cards, debit cards or smart cards, tickets, notes, etc. When a player inserts money in gaming device 10 , a number of credits corresponding to the amount deposited is shown in a credit display 16 . After depositing the appropriate amount of money, a player can begin the game by pulling arm 18 or pushing play button 20 . Play button 20 can be any play activator used by the player which starts any game or sequence of events in the gaming device.
[0027] As shown in FIGS. 1A and 1B , gaming device 10 also includes a total bet display 22 and a bet one button 24 . The player places a bet by pushing the bet one button 24 . The player can increase the bet by one credit each time the player pushes the bet one button 24 . When the player pushes the bet one button 24 , the number of credits shown in the credit display 16 decreases by one, and the number of credits shown in the bet display 22 increases by one. The wagering is discussed in more detail below. At any time, except while the reels are spinning, a player may “cash out” by pushing a cash out button 26 to receive coins or tokens in the coin payout tray 28 or other forms of payment, such as an amount printed on a ticket or credited to a credit cards, debit cards or smart cards. Well known ticket printing and card reading machines (not illustrated) are commercially available.
[0028] The gaming device of the present invention may also include one or more display devices. The embodiment shown in FIG. 1A includes a central display device 30 , and the alternative embodiment shown in FIG. 1B includes a central display device 30 as well as an upper display device 32 . The display devices may display any visual representation or exhibition, including but not limited to movement of physical objects such as mechanical reels and wheels, dynamic lighting and video images. The display device may include any viewing surface such as glass, a video monitor or screen, a liquid crystal display or any other static or dynamic display mechanism.
[0029] The slot machine primary game of gaming device 10 preferably displays a plurality of reels 34 arranged in at least two, and preferably three, separate sets 100 a , 100 b and 100 c . Each set preferably has three to five reels 34 in video form on one or more of the display devices. Each reel 34 has an identical plurality of indicia such as bells, hearts, fruits, numbers, letters, bars or other symbols or images which preferably correspond to a theme associated with the gaming device 10 . The display device displaying the video reels 34 is preferably a video monitor. The gaming device 10 also includes speakers 36 for making sounds or playing music.
[0030] Referring now to FIG. 2 , a general electronic configuration of the gaming device 10 for the stand alone and bonus embodiments described above preferably includes: a processor 38 ; a memory device 40 for storing program code or other data; a central display device 30 ; an upper display device 32 ; a sound card 42 ; a plurality of speakers 36 ; and one or more input devices 44 . The processor 38 is preferably a microprocessor or microcontroller-based platform which is capable of displaying images, symbols and other indicia such as images of people, characters, places and things. The memory device 40 can include random access memory (RAM) 46 for storing event data or other data generated or used during a particular game. The memory device 40 can also include read only memory (ROM) 48 for storing program code which controls the gaming device 10 so that it plays a particular game in accordance with applicable game rules and pay tables.
[0031] As illustrated in FIG. 2 , the player preferably uses the input devices 44 to input signals into gaming device. In the slot machine base game, the input devices 44 include the pull arm 18 , play button 20 , the bet one button 24 and the cash out button 26 . A touch screen 50 and touch screen controller 52 are connected to a video controller 54 and processor 38 . The terms “computer” or the “controller” are used herein to refer collectively to the processor 38 , the memory device 40 , the sound card 42 , the touch screen controller and the video controller 54 .
[0032] In certain instances, it is preferable to use a touch screen 50 and an associated touch screen controller 52 instead of a conventional video monitor display device. A player can make decisions and input signals into the gaming device 10 by touching touch screen 50 at the appropriate places. As further illustrated in FIG. 2 , the processor 38 connects to the coin slot 12 or payment acceptor 14 , whereby the processor 38 requires a player to deposit a certain amount of money in to start the game.
[0033] It should be appreciated that although a processor 38 and memory device 40 are preferable implementations of the present invention, the present invention can also be implemented using one or more application-specific integrated circuits (ASIC's) or other hard-wired devices, or using mechanical devices (collectively referred to herein as a “processor”). Furthermore, although the processor 38 and memory device 40 preferably reside on each gaming device 10 unit, it is possible to provide some or all of their functions at a central location such as a network server for communication to a playing station such as over a local area network (LAN), wide area network (WAN), Internet connection, microwave link, and the like.
[0034] With reference to the slot machine base game of FIGS. 1A and 1B , to operate the gaming the device 10 , the player inserts the appropriate amount of money or tokens at coin slot 12 or bill acceptor 14 and then pulls the arm 18 or pushes the play button 20 . Each set of reels 100 a , 100 b and 100 c will then simultaneously spin. It can be appreciated that the number of sets of reels spinning can be determined by the amount of credits the player wagers. The gaming device also includes buttons or other indicators (not shown) which enable the player to select paylines and wager on individual paylines. Eventually, the reels 34 will come to a stop. As long as the player has credits remaining, the player can spin the reels 34 again. Depending upon where the reels 34 stop, the player may or may not win additional credits.
[0035] In addition to winning base game credits, the gaming device 10 , including any of the base games disclosed above, may include one or more bonus games that give players the opportunity to win credits. Bonus games include a program that automatically begins when the player achieves a qualifying condition in the base game. The gaming device may also employ a video-based central display device 30 or 32 for the bonus game.
[0036] The qualifying condition may include a particular symbol or symbol combination generated on a display device. As illustrated in the multiple reel slot game shown in FIGS. 1A and 1B , the qualifying condition includes the number seven appearing on three adjacent reels 34 along a payline 56 in the set of reels 100 c . It should be appreciated that the present invention includes one or more paylines 56 in at least two sets of reels 100 , wherein the paylines 56 can be horizontal, diagonal on any set of reels 100 or in certain positions on each set of reels 100 or any combination thereof.
Multiple Identical Sets of Reels
[0037] A player initiates the gaming device 10 by inserting a predetermined number of credits needed to play the base game. The gaming device determines if randomly generated gaming symbols on paylines 56 , which the player wagered on, match predetermined symbols or combinations of symbols. If randomly generated gaming symbols on a payline 56 or paylines 56 matches a predetermined symbol or combination of gaming symbols, the player is awarded one or more credits. The present invention may also include scatter pays.
[0038] As indicated above, one embodiment includes a central display device 30 displaying three identical sets of reels 100 a , 100 b and 100 c , with each set consisting of five reels 34 and a plurality of gaming symbols on each reel. Other embodiments may have two or more than three sets of reels. Yet other embodiments may have two or more sets of reels consisting of more or less than five reels 34 . It should be appreciated that there may be more displays, such as a bet display for each set of reels and for each payline 56 whereby a player sees the bet associated with each payline 56 .
[0039] In one embodiment of the present invention, a player initiates the base game in accordance with the gaming scheme as indicated by block 60 in FIG. 3A and FIG. 3B . The player inserts the appropriate amount of credits 60 required to play the base game. The player wagers a bet as indicated by block 62 on the base game. The game evaluates if the bet is large enough for the player to play multiple paylines as indicated by block 64 . If the bet is large enough, the game prompts the player to choose another set of reels to put into play as indicated by block 78 . If the player selects more than one set of reels to play, the game chooses at least one payline 56 on each set of reels the player chose as indicated by block 80 .
[0040] In another alternative embodiment, the player chooses the paylines 56 on each set of reels 100 a , 100 b and 100 c to put into game play using a payline button (not shown) as indicated by block 96 . The player simultaneously activates the sets of reels chosen as indicated by block 82 by pulling the arm 18 or pushing the play button 20 . The plurality of reels 34 spins simultaneously. The game displays randomly generated game symbols on the sets of reels 100 a , 100 b and 100 c as indicated by block 84 . The game evaluates the paylines 56 on the sets of reels 100 a , 100 b and 100 c chosen by the player for winning symbol or combination of gaming symbols 86 .
[0041] If there is a symbol or a combination of gaming symbols on a payline 56 in game play which matches a predetermined winning symbol or a combination of gaming symbols on the paylines chosen by the player, the player is awarded credits as indicated by block 76 .
[0042] With the availability of more than one set of reels, it should also be appreciated that new winning combinations of gaming symbols and winning combinations utilizing the plurality of sets of reels for credits and bonus games can be implemented. One embodiment of the present invention provides a greater variation to a traditional “scatter pay” award scheme. A player is awarded credit(s) or bonus game(s) in “scatter pay” when a predetermined number of the same symbol appears on a set of reels. An embodiment of the present invention provides an improved chance of winning on certain “scatter pay” rounds where the greater number of sets of reels provide a higher chance for the same gaming symbol to appear. Higher occurrences of the same gaming symbol in “scatter pay” can be associated with more frequent payouts which provides greater excitement to the player. Different combinations of gaming symbols on different sets of reels can also employed. For example, a payout can be given when one gaming symbol appears on the first set of reels 100 a , and the same gaming symbol appears twice on the second set of reels 100 b , and the same gaming symbol appears three times on the third set of reels 100 c.
[0043] Another embodiment of the present embodiment provides novel ways of winning by utilizing the plurality of sets of reels. For example, a player can place a bet on which sets of reels (i.e., 100 a , 100 b or 100 c ) will have a winning or other combination of symbols appear on a payline 56 . It can be appreciated that a player can also place wagers on different combinations of sets of reels on which predetermined combinations of symbols appear on paylines 56 or in the alternative place a bet on which set of reels will not have a winning or other combination of symbols appear on a payline 56 . A player can also be awarded credits or one or more bonus games if more than one sets of reels have winning combinations of symbols on paylines 56 . In one such embodiment, a player is awarded a jackpot or bonus award if the same combination of symbols appears on a payline 56 in two or more sets of reels 100 .
[0044] In another embodiment, a player can play a wildcard payline 56 which may appear on any one of the plurality of sets of reels. The player is awarded credit when a winning combination of symbols appears on any payline 56 in any of the sets of reels. A player can also be awarded credit when a player bets that one particular combination of symbols will appear on a payline 56 in any of the sets of reels.
[0045] In another embodiment as depicted in FIG. 4 , each coin bet triggers at least one payline 56 . If one coin is bet on all nine paylines 56 in the first set of reels 100 a and an additional coin is wagered, the next coin bet is placed on the tenth payline or the first line in the second set of reels 100 b . As the player places additional bets the display may indicate to the player which paylines 56 are in play. Similarly, a bet of the nineteenth coin is a bet on a payline 56 in the third set of reels 100 c . In another embodiment, the player can initiate a wager on each payline 56 individually. The player can bet any amount of coins on any of the twenty-seven paylines 56 , up to a certain maximum number of coins on each payline 56 . Thus, in one embodiment, the player may wager five coins on each of the twenty-seven paylines 56 or 135 coins for the game.
[0046] In another alternative embodiment of the present invention, the central display 30 displays all of the sets of reels spinning simultaneously during game play or displays only the sets of reels spinning that are in actual game play. Yet another alternative embodiment is that the central display 30 can display the sets of reels not chosen by the player in a simultaneous demonstration during game play. This demonstration can be made to provide the player with information on other paylines 56 not wagered on by the player thereby providing greater excitement by offering more paylines 56 to the player.
[0047] While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but on the contrary is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the claims. It is thus to be understood that modifications and variations in the present invention may be made without departing from the novel aspects of this invention as defined in the claims, and that this application is to be limited by only the scope of the claims. | The present invention involves a gaming device that provides a primary game which utilizes multiple sets of identical reels. The sets of reels simultaneously spin. A player is able to wager on paylines on one or more of said sets of reels. The gaming device also allows a player to wager on predetermined combinations of gaming symbols which occur over the plurality of sets of reels. The method of the present invention enables a player to simultaneously play multiple paylines on a plurality of identical sets of reels. The method enables a player to easily see different paylines by reducing the complexity of such paylines and duplicating paylines on sets of reels. The method provides novel arrangements of wagering combinations between the sets of reels which provide additional excitement to players. The method also reduces the complexity of software needed to evaluate multiple paylines. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to an improved instantaneous photography camera. More particularly, the present invention comprises a multiple masked instantaneous photography camera allowing the image of a subject to be positioned upon a photo identification card in with credit information of the subject.
Instantaneous formation of credit cards is desirable in order to provide an economic means for manufacturing large numbers of credit identification media. Conventional apparatus utilized to provide instantaneous photography generally comprise one or more fixed masks positioned within a camera box with associated lens and shutters assemblies. The masks expose various portions of the photosensitive film within the camera box to light, providing an image of the subject and an image of the subject's credit information to form the photo identification card. In another further form of conventional apparatus photographic masks are placed upon and moved across the photosensitive film in order to provide a means for exposing specific areas of the photographic sensitive film to light imagery card.
Each of the conventional apparatus disclosed and discussed herein exhibit the same inherent problem in that they fail to provide a rapid means for positioning imagery upon a photosensitive film. A further problem is presented in that the movement of a prism, lens or mask about a photosensitive film requires continuing refocusing of the lens in order to gain exact focus of the imagery. What is required is an apparatus which provides instantaneous photographic imagery for photograph identification card usage.
It is an object of the present invention to provide an improved instantaneous photography camera for use in the manufacture of photographic identification cards.
It is further object of the present invention to provide an improved instantaneous photography camera utilizing two masks pivotally positioned within a camera.
It is still a further object of the present invention to provide an improved instantaneous photography camera. Said camera utilizing two pivotally positioned masks contained within a camera box and having means for holding the camera to allow for the positioning of both the subject and his credit information upon a photosensitive film contained within the instantaneous photography camera.
With these and other objects in mind, the present invention may be more readily understood through referral to the accompanying drawing and the following discussion.
SUMMARY OF THE INVENTION
The objects of the present invention are most readily achieved through utilization of apparatus forming an improved instantaneous photography camera for use in the manufacture of photographic identification cards. The improved camera is of the type in which one or more masks are provided within the camera box of the camera to allow the sequential exposure of a portion of the photosensitive film to information and an image of the subject of the credit identification at any moment. The improvement comprising a first mask pivotally positioned within the camera box with its pivotal axis perpendicular to the focal axis of the lens of the camera and being formed adequate weight so as to normally hang in a vertical position when the camera box is held having its lens axis parallel to the horizontal of the ground and so to normally cover a portion of the photosensitive film. The normally covered portion of the photosensitive film is exposed when the camera lens is directed in a vertical position towards the ground. The improvement further comprises a second mask pivotally positioned within the camera box with its pivotal axis parallel to the pivotal axis of the first mask and being counterweighted so as to be normally positioned in a horizontal position when the camera box is held having its lens axis parallel to the ground and so as to normally leave exposed the photosensitive film. The normally exposed portion of the photosensitive film is covered when the camera lens is directed in a vertical position towards the ground.
The first mask may be constructed so as to have the given shape of the credit information to be exposed upon the photosensitive film and the second mask constructed having the general given shape of the subject of the credit identification card. The first and second masks form in combination, the outline of the credit identification card.
In still a further preferred embodiment of the present invention the improved instantaneous photography camera may further comprise means for holding the camera with its lens in a vertical position directed downwardly and for holding the credit information of the subject at the focal distance before the lens of the camera. In general these means may comprise a base having a credit information holder positioned thereon. An upright support is attached to the base and has a camera holder positioned upon the upper portion of the upright support. A lens holder hole passes through the camera hole and is aligned with the credit information holder. In still a further preferred embodiment said lens holder hole has an adapter lens positioned within the lens holder hole so as to provide a focal media for the lens of the instantaneous photography camera when it is positioned therein.
BRIEF DESCRIPTION OF THE DRAWINGS
The object of the present invention may be more readily understood through referral to the accompanying drawing which represents an exploded view of one embodiment of the apparatus of the improved instantaneous photography camera of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
In general, the apparatus of the present invention comprises a camera having the ability of forming a complete image of a photographic identification card upon a photographic print. The camera includes conventional lens and shutter assembly, and strike contained thereon the camera box having film advancement apparatus contained thereon. The apparatus exhibits a focusing ability to allow a predetermined portion of the photosensitive film contained within the camera box to be exposed to an image of a subject of the credit identification. The apparatus further provides a means for positioning credit information thereupon the remaining unexposed portion of the photosensitive film contained within the camera box utilizing the same focusing lens and shutter assembly.
A particular embodiment of the apparatus of the present invention may be more readily depicted through referral to the accompanying drawing. Specifically, the drawing is an exploded view of a preferred embodiment of the apparatus for an improved instantaneous photography camera for positioning a subject and his credit information upon a photosensitive film. Instantaneous photography camera is depicted having camera box 12 with film pack and advancement means 16 contained on a rear portion of camera box 12. The instantaneous photography camera 10 is provided with a standard lens and shutter assembly 18 having a shutter activation knob 20 positioned upon the face of the camera box 12 and in alignment with the shutter of the lens and shutter assembly 18. The camera 10 contains a first mask 28 pivotally positioned within the camera box 12 and of adequate weight so as to normally hang in a vertical position. Therefore when the camera box 12 is held having its lens axis parallel to the horizontal of the ground the first mask 28 normally covers a portion of the photosensitive film. That portion of the photosensitive film is exposed when the camera lens 18 is directed in a vertical position toward the ground. It is preferred that the first mask 28 be constructed of a given shape of the credit information to be exposed upon the photosensitive film and that it be pivotally connected to the camera box 12 through utilization of a pivot arm 30 connected to adjacent sides of the camera box 12. A second mask 22 is provided being pivotally positioned within the camera box 12 through means of pivot arm 24 and being counter-weighted so as to be normally positioned in a horizontal position when the camera box 12 is held having its lens axis 18 parallel to the ground. This positioning normally leaves exposed the photosensitive film contained therein the camera box cavity 14 of the camera box 12 but allows that portion of photosensitive film to be covered when the camera lens 18 is directed in a vertical position toward the ground. The second mask 22 generally has a given shape of the subject of the credit identification card and forms in combination with the first mask the outline of the credit identificatio card. As depicted in this embodiment of the present invention the first mask is formed of a rectangle having a rectangular corner portion thereof removed and the second mask is formed of a rectangle of the size of the portion removed from the first mask so to in combination therewith form a rectangle.
The improved instantaneous photography camera of the present invention may further comprise means for holding the camera 12 with its lens 18 in a vertical position directed downwardly and for holding the credit information of the subject at the focal distance before the lens 18 of the camera 10. In general these means may be provided as depicted in the preferred embodiment shown in the drawing through utilization of a base 34 containing a credit information holder 36 positioned thereon said base and having an upright support 32 connected to said base and extending vertically therefrom. A camera holder 38 is fixed upon the upright support 32 and further having a lens holder hole 40 passing therethrough the camera holder 38. Said hole being aligned with the credit information holder 36 positioned upon the base 34. The improved instantaneous photography camera of the present invention may further comprise an adapter lens 42 positioned within the lens holder hole 40 of the apparatus. Said adapter lens 42 being sized so as to act in combination with lens 18 of the camera 10 to provide a focusing of the credit information contained within the credit information holder 36. The apparatus is further provided with one or more studs 44 which act in combination with the sides of the camera 10 in order to provide a rigid affixation of the camera 10 as it is positioned with the lens 18 contained within the lens holder hole 40 of the camera holder 38.
In the operation of the apparatus of the present invention the improved instantaneous photography camera 10 is first positioned with the axis of the lens 18 being parallel to the ground so that the camera is held in a vertical position with a focusing through the lens and shutter assembly 18 of the image of the subject of the credit identification. In this position the first mask 28 hangs in a vertical position covering a portion of the photosensitive film upon which credit information will be subsequently exposed and the second mask 22 lies in a horizontal position leaving exposed a portion of the photosensitive film upon which the image of the subject is provided. The shutter activation knob 20 is depressed allowing the image of the subject to pass through the lens and shutter assembly 18 and to expose a predetermined portion of the photosensitive film contained within photosensitive film pack 16. Camera 10 is positioned in a horizontal position having the axis of the lens and shutter assembly 18 perpendicular to the ground with the lens and shutter assembly 18 being positioned within a camera holder 18. The lens 18 is passed within the lens holder hole 40 thereof the camera holder 38 and having the positioning studs 44 passed about the exterior of the camera box 12 so as to readily affix the camera 10 to the camera holder 38. Credit identification information is provided within the credit information holder 36 said information being positioned on the credit information card as depicted in the drawing. The information card having a general conformity of the shape of the first mask 28 such that the image which passes through the lens and shutter assembly 18 upon the activation of shutter activation knob 20 will expose that portion of the photosensitive film normally covered by first mask 28. The portion containing the subject image being covered by the second mask 22 held in a horizontal position over the photosensitive film within the photosensitive film pack 16. The credit information is positioned upon the film in conjunction with that portion of the film already exposed and containing the subject's image. Thereafter the credit identifying information is positioned or exposed upon the photosensitive film contained within the camera 10 the photosensitive film is advanced and the instantaneous photograph is withdrawn from the camera and laminated within plastic to produce a photographic identification card. The multiple imagery yields to the operator a single photographic print with distinct images which may be embossed and utilized as a photographic identification card.
The present invention has been described herein with reference to particular embodiments thereof. It will be appreciated, however, by those skilled in the art, that various changes and modifications may be made without departing from the scope of the invention as set forth herein. | Disclosed herein is an improved instantaneous photography camera for use in the manufacture of photographic identification cards. The camera is of the type in which one or more masks are provided within the camera box of the camera to allow the sequential exposure of a portion of photosensitive film to an image containing credit information and an image of the subject of the credit identification to form a photographic identification card. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to a fire-control system, and in particular to a fire-control system adapted for use with a weapon firing ammunition with a relatively high trajectory or firing with low-trajectory ammunition at longer distances. The invention also relates to a method of displaying a reticle and to a computer program for executing said method.
TECHNICAL BACKGROUND
[0002] When using ammunition with low exit velocity, high trajectory or firing at targets at a significant distance, where the time of flight is significant, the weapon sight has to have certain properties. In such conditions the barrel of the weapon needs to have a considerable elevation in order for the ammunition to reach the target. A normal sight will generally not suffice, since it is difficult or impossible to have a visual contact with the target via the sight and at the same time have the correct inclination of the barrel, thus aiming is impossible. Also the sight may need to cover a considerable interval of inclinations, which introduces further limitations. In this context it should be clarified that some weapons/ammunitions have an inherent high trajectory, while others only have high trajectory when applied under certain conditions, e.g. ammunition normally following a level trajectory in shorter ranges will generally fall within the definition of high trajectory if the distance they travel to the target is considerable. For the purpose of the present invention this is the relevant definition of high trajectory.
[0003] The known solution to the above problem has been to incorporate an iron sight, similar to those used for historical long guns, with a foldable primary part including distance markings, e.g. tang sight or ladder sight, such that if the distance is known, the correct distance marking can be used. This type of sight is still used, since it provides a rugged, simple solution.
[0004] More elaborate solutions include advanced optics, mechanics and computer software for calculating optimal aiming, and movement of a physical light-source inside the sight (see e.g. WO2004001324).
[0005] Though functional, more elaborate solutions generally are too complicated and thus not as rugged as one would prefer for field use or too heavy to be handheld with maintained user friendliness. The existence of moving parts inside the sight generally also increase power consumption, increase the response time, and makes the sight less versatile.
[0006] The present invention aims at providing a fire-control system relating to these and other drawbacks in prior-art.
SUMMARY OF THE INVENTION
[0007] When using high-trajectory ammunition in a field condition it is obviously important to maintain an elevated awareness regarding the events in the surroundings. Therefore it is beneficial and desired to have a fire-control system that does not include optics or electronics distorting the field of view, e.g. an optical or electronic system that creates a real or imaginary image of the target which is not in the line of sight between the aiming eye of the user and the actual target. Also, it is beneficial to be able to look at the target with the other eye while aiming.
[0008] The present invention aims at alleviating or eliminating the above and previously mentioned drawbacks and achieving the above benefits by the provision of a fire-control system in accordance with claim 1 , and a method of displaying a reticle in accordance with claim 10 and a computer program in accordance with claim 15 Further embodiments are defined in the dependant claims.
[0009] It should be noted that even though the present fire-control system is especially well adapted for the purposes mentioned in the introduction, it may be used on any weapon to increase precision and first shot accuracy. It should also be noted that though the inventive fire-control system will been described by specific embodiments, it is, unless technically unfeasible, possible to add, remove or combine individual technical features of the sight to create new embodiments, not described. This is particularly true for the features defined in the appended claims.
[0010] To this end an inventive fire-control system comprises:
[0011] a housing; partially reflective optics, through which a user may observe a target and receive visually displayed information simultaneously; a light source, for visualization of a reticle to the user via the partially reflective optics; means for receiving a measure of the distance to the target; a processor, for determining the adequate position of the reticle, based on the distance to the target, and for controlling the light source to emit light so that the reticle is visualized at the adequate position; wherein the light source is an capable of selectively emitting light in well defined locations on its surface. According to one or more embodiments the fire-control system may also comprise a battery charge controller.
[0012] The use of said array provides several advantages over prior art, and in one or more embodiments the array is a one-dimensional array. A one-dimensional light-emitting array is in this context defined by a light source capable of emitting light from well-defined points on its surface, along one specific direction. The light-emitting array is a static component in the sense that it remains immovable during the operation of the fire-control system. A static component may be made more robust, as compared to a mobile component serving the same purpose. Further, several other components may be eliminated, such as the drive, suspension, guide means, etc. which are necessary if a mobile light source is used. This elimination reduces overall weight, chock sensitivity, power consumption and, not the least, cost.
[0013] The main purpose of the sight is obviously to assist the user in striking the target, and the fire-control system will provide a reticle to be superimposed on the target. It should be noted that there are other possibilities than to superimpose a reticle. The reticle could have another form, such as a crosshair form or a circular form, and these embodiments fall within the scope of the claim. The light-emitting array enables the display of a reticle, which is movable in a vertical direction, so as to be able to mark an aiming point for various distances to a target.
[0014] According to one or more embodiments the one-dimensional array may be curved, such as to adjust for, e.g., a known drift caused by the rotation of a projectile (i.e. the gyroscopic drift) without a need to move the one-dimensional array.
[0015] The position of the reticle is calculated on basis of the measured distance to the target. Further, the one-dimensional array makes it possible to emit light from several points of the array at the same time, which increases the functionality of the fire-control system. In the case of a miss of the target, the possibility of displaying several reticles may be useful when correcting the position of the reticle, e.g. by letting the used reticle remain on the target while another reticle is electronically moved the actual point of impact. In this way the processor may correct the calculation of the reticle so that the next firing will result in a hit.
[0016] The processor may include tables and/or algorithms regarding the performance of various types of ammunition. The apparent parameter needed is related to the trajectory for various distances, since the position of the reticle relies on this type of data. However, the processor enables far more advanced maneuvers, such as correction for wind speed, inclination, air pressure, humidity, corrections etc, and makes the fire-control system very versatile. Therefore, in one or more embodiments the fire-control system may also contain data regarding various types of ammunition, and in such cases this data is included in the acquisition of the position of the reticle. This acquisition may also include data regarding air speed, air temperature, humidity, tilt of the weapon in a cross direction, and other factors affecting the trajectory of the ammunition, and the choice of reticle. One further example is that there are two elevations for which the ammunition will hit the target, a lower elevation—resulting in a lower trajectory—and a higher elevation—resulting in a higher trajectory. Depending on the type of target, the terrain in front of the target, and the ammunition either the higher or the lower trajectory may be preferred. By providing the desired scenario to the CPU it may, if geometrically possible, show either one or both of the applicable reticles.
[0017] In the above context the term “position” relates to the position in a plane orthogonal to the line of sight between the eye of the user and the target. However, in many applications it is also important at what distance from the users eye the image of the lit part, i.e. the reticle, of the light source is located.
[0018] In one or more embodiments the light-emitting array is a two-dimensional array capable of selectively emitting light in well-defined locations on its surface. The two dimensional array makes the fire-control system even more versatile, since it enables the position of the reticle to be varied in the horizontal direction as well. This makes it possible to correct the position of the reticle in relation to offsets due to wind, poor alignment etc. The use of a two-dimensional light-emitting array facilitates software tuning of the fire-control system, making the production and quality assurance faster and less costly. When zeroing the weapon it may simply be fired at a target, after which the reticle is manually (by using input means for communication with the fire-control system) translated to the actual hit, after which the weapon is tuned for that particular type of ammunition. This results in a markedly decrease in ammunition and time consumed during tuning.
[0019] In one or more embodiments the fire-control system may be combined with equipment for infrared illumination and/or night-vision systems, which may increase the usability of the fire-control system.
[0020] The fire-control system according to one or more embodiments may also comprise a range finder, active or passive, within its housing. The use of an integrated rangefinder increases the fire-control systems versatility even further. Instead of relying on external data the user may now measure the distance to the target while looking through the fire-control system. The risk of potential misunderstanding decreases and the hit rate is likely to increase. The rangefinder is generally laser based and it should obviously not be subject to any trajectory correction, whereby a reticle related to the rangefinder may be displayed at all times when the fire-control system is in use.
[0021] The optics displaying the reticle for the user may comprise optics being adapted to create an image of the reticle which is essentially parallax free relative to the target. An essentially parallax free reticle significantly simplifies the task of the user, since there is no requirement to align any other components than to simply superimpose the reticle on the target and fire. If high-trajectory ammunition is used, the sight window through which the user observes the target is generally significantly larger than what is used for a normal telescopic sight since it should allow for a significant inclination of the weapon, and thus of the fire-control system, with maintained visual contact with the target through the fire-control system. An essentially parallax free reticle is generally created by having the optics generating an image at an infinite distance from the user, or at a typical distance for use, such as 300 m. This also means that the normal human eye may be relaxed, for the benefit of the user's ability to concentrate during long time. If the reticle is located at an infinite distance from the users eye, or 300 m, and the target is located 100 m away, there will be some parallax, though it has no significant impact on the precision of the weapon, as long as the user may still superpose the reticle on the target while looking in the fire-control system. Due to the fact that targets will be located at various distances a completely parallax free reticle is very difficult to achieve, which is why the word “essentially” have to be included. For the purpose of this invention “essentially parallax free” optics having inherent very low dependency on distance to observed object with regard to showing little or no parallax effects.
[0022] To further increase the versatility of the fire-control system according to one or more embodiments it may further comprise a gyro or other inclinometer for enabling measurement of the inclination of the fire-control system. Combined with the distance being known, a measure of the inclination makes it possible to account for an altitude difference between the fire-control system and the target, and to make the necessary corrections regarding trajectories and the calculated reticle. The gyro or inclinometer may obviously be combined with the capability of measuring the direction of the fire-control system in accordance with an established positioning standard, so that the processor of the fire-control system may calculate an absolute position of a target or itself The gyro or inclinometer may also be used for determining rate of angular change and thereby the speed of the target and aim-off (lead) necessary in regard of a moving target etc. To that end the fire-control system may also comprise a positioning system, such as a Global Navigation Satellite System (GNNS), e.g. Navstar Global Positioning System (GPS) or an alternative positioning system. A compass may also be included, for measuring the direction of a target in relation to the fire-control system.
[0023] A fire-control system according to one or more embodiments may further comprise means for communication with external sources. The means for communication may be realized by regular connectors for keypads, transfer of data etc, and may also comprise means for communication with wireless means, such as a receiver/transmitter for electromagnetic radiation, radio frequency communication, etc. There are several cases when this may constitute an advantage, one example being the fire-control system receiving information regarding wind speed or other atmospheric conditions.
[0024] A method for displaying a reticle for a fire-control system according to one or more described embodiments during targeting with specific ammunition, comprises the main steps conducted during use of the fire-control system:
[0025] acquiring distance information representing a distance to a target;
[0026] determining a position for imaging the reticle based on said distance information and trajectory information for ammunition to be used; and
[0027] controlling light emission from the array to emit light from a position of the surface of the array which via the partially reflective optics images reticle at the determined position.
[0028] In the step related to acquiring distance, may also include acquiring alternative or additional inputs may be used, some examples of which is illustrated in relation to FIG. 2 . Further, the step of acquiring distance may include the substeps of:
[0029] transmitting electromagnetic radiation towards the target;
[0030] receiving a reflection of said electromagnetic radiation from the target; and
[0031] calculating the distance to the target based on the time elapsed from the transmitting to the receiving.
[0032] A computer program for performing the method may be embodied on a computer-readable medium.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is a schematic illustration of the fire-control system according to a first embodiment of the invention, in a side view.
[0034] FIGS. 2A and 2B illustrate various configuration of a light-emitting array.
[0035] FIG. 3 is a block diagram illustrating the operations performed by the fire-control system of FIG. 1 .
[0036] FIGS. 4 and 5 are perspective views of a fire-control system in accordance with an embodiment of the present invention.
[0037] FIG. 6 is a perspective view of a grenade weapon having a handle adapted for control of the fire control system.
[0038] FIG. 7 is a flow chart of a method for displaying a reticle in a fire-control system in accordance to the invention.
[0039] FIG. 8 illustrates a computer program for executing the method of FIG. 7
DESCRIPTION OF EMBODIMENTS
[0040] The general structure and function of the inventive fire-control system in the embodiment of a sight 1 is described referring to FIG. 1 , which is a schematic representation of the sight, as viewed from one side. In the depicted view a target would be situated to the right, and the user to the left. The user may observe the target directly through a light channel housing an entrance window 2 , an angled narrow-banded reflector 4 , a dual lens system 6 , 8 , and a protective exit window 10 having essentially the same purpose as the entrance window 2 . The entrance window 2 may also consist of a lens, which may be used to correct for possible distortions. All components will be defined in the following, and one important feature of the optical components are that they do not disturb the light path from the target to the eye of the user to any significant degree, by introducing distortion. It is also to be understood that the sight 1 as such is non-magnifying. A user may therefore observe a target in a direct fashion and with both eyes open, as oppose to a system that may use a camera and a display, or a system shifting the light-path in some way. The general purpose of the sight is to display a reticle at the correct position. Starting from the left the entrance window 2 acts as a protective window, and is arranged to enable moist sealing and dust sealing of a practical system. The next component is the inclined reflector 4 , which is more intimately related to the imaging system and thus will be described later. Two spherical lenses 6 , 8 of the dual lens system are arranged at the other end of the light channel, opposite to the protective window 2 . The two lenses 6 , 8 , which are spherical, together perform the function of a parabolic mirror in relation to a reticle, which also will be described in relation to the imaging system. The imaging system of the fire-control system comprises a two-dimensional array 12 of light emitting diodes, preferably resonant cavity light emitting diodes (RCLED), which may be arranged to be very energy efficient, which is described in a previous application by the same applicant in relation to a single RCLED. In the following the two-dimensional array of RCLED:s will only be referred to as the “array” 12 . The array 12 may be fully controlled via input from a CPU (not shown), so as to emit light from selected portions of its surface. Light from the array 12 will pass through a first and a second lens, 14 and 16 , respectively, which together with the inclined reflector 4 generates an image of the array 12 placed in the focal plane of the lens system 6 , 8 , which in turn reflect the beams and generates a parallax free image of the array 12 for a user. By activating selected areas of the array 12 the user will consequently be able to observe a reticle (or other another type of indication) overlaying the target. The array 12 has a well defined wavelength λ a and the first and second lens 14 , 16 transmits λ a . The inclined reflector 4 reflects a portion of light having a wavelength λ a , towards the lens system 6 , 8 . The lens system 6 , 8 is adapted to reflect as much light having the wavelength λ a while transmitting light of any other wavelength. In this way a user may observe the target and the reticle simultaneously.
[0041] The imaging system, including the array 12 , the lenses 14 , 16 , the inclined reflector 4 and the lens system 6 , 8 are preferable integrated into a unit, such as to enable a rigid and robust construction able to maintain adequate precision while being handled roughly.
[0042] In one or more embodiments the light-emitting array 12 comprises a two-dimensional diode array of close-packed diodes (RCLED:s) having low power consumption. Such a diode array may be custom-built by IRnova (SE) or PRP Optoelectronics (GB). The wavelength of the emitted light is approximately 650 nm, well within the visible range, yet far enough from wavelength range where the human eye is the most sensitive (around 555 nm). The array may be quadratic or rectangular or have other more complex shapes, as will be described below.
[0043] FIGS. 2A and 2B illustrate two alternative embodiments of arrays 12 , which may be used in relation to the present invention. The array disclosed in FIG. 2A is of standard design in regard of its shape, and the array of FIG. 2B has been invented for use in the present fire-control system and has a trapezoid shape. The shorter of the parallel sides of the trapezoid has a width of about 30-50 pixels, e.g. 40 pixels, and the longer of the parallel sides has a width of about 100-140 pixels, e.g. 120 pixels. The distance between the parallel sides may be about 150-200 pixels, e.g. 175 pixels.
[0044] Giving the array a trapezoid shape will result in several advantages, all relating to the fact that the function of the array will be maintained while its area will be reduced (both as compared to a conventional rectangular array). Firstly, and perhaps most importantly, the present applicant has not revealed any significant disadvantages, which makes it easier to appreciate the advantages. One advantage is that during production the array is cut from a substrate, and the inventive design enables more arrays to be produced from the same substrate. The array of FIG. 2B is arranged in the fire-control system 1 so that the narrow end may be used to image the reticle for targets being far away. The shape of the array results in a fewer number of pixels, which increases the yield during production.
[0045] The lens system 6 , 8 may be coated so as to act as a bandpass filter, transmitting all visible wavelengths between 420 and 1100 nm but for a narrow wavelength interval including the wavelength emitted by the array 12 , which itself is reflected. The longer wavelength are used for Night Vision Device (NVD).
[0046] Since the light from the array has a wavelength of e.g. 650 nm, most light will be transmitted, and in particular light in a wavelength range where the human eye is most sensitive.
[0047] The image generated is a virtual image created at an infinite distance from the user, in order to relax the eye of the user maximally. The user may observe the image through the protective window 2 , the same window through which the target is observed. A second protective window 10 may, as have been mentioned above, be arranged in front of the lens system 6 , 8 . This protective window 10 may be inclined order to avoid reflections visible from the target area. Apart from protecting the sight from physical damage, the protective window 10 may also be coated to prevent transmission of hazardous radiation, such as infrared radiation from laser rangefinders, and in the absence of a second protective window 10 such coating may be provided on another optical surface of the system. Further, all optical surfaces may be coated with an anti-reflection (AR) coating to increase transmission. If external reflections are to be avoided the sight may be provided with a “killflash filter”.
[0048] A third part of the sight may house the optional laser rangefinder 18 (see FIGS. 4 and 5 ), which may be of standard type operating at 1550 nm (not visible with standard night-vision systems) as well as the processing hardware, software and storage capabilities utilized. Other standard wavelengths used are around 900 nm, still in the infrared, and visible light. The latter having the disadvantage of exposing a visible flash of light. The laser rangefinder 18 is operated by the user, and the result of a distance measurement is used as an input to the processing section of the sight 1 . The laser beam of the rangefinder will follow a rectilinear path, and thus a reticle for the rangefinder may be displayed at the same position in disregard of the distance to the target. The use of an integrated rangefinder 18 is preferred and preferable features for the rangefinder 18 for the intended application is high reliability and accuracy, low power consumption and low weight. In one or more embodiments the rangefinder may be tailor-made by Vectronix or JENOPTIK AG (DE), to fulfill the above preferences. These features are also important for the processing hardware, software and storage capabilities utilized. Existing possible processors include a main processor in the fire-control system and a processor in the handle (to be described referring to FIG. 6 ) both having a power consumption in an idle state of 0.1 μA. For other applications the weight and power consumption may be less important, and the sight need not be optimized in regard to the above parameters. All components of the fire-control system may preferably be statically mounted, such as the array 12 , and both the lens systems 14 , 16 and 6 , 8 , as well as the inclined reflector 4 . As has been mentioned before, this will increase the ruggedness of the fire-control system as compared to a system where interior components are movable. There may be embodiments of the present invention too, however, that offer movable components, even if this is not the preferred construction.
[0049] Apart from visualizing the reticle, the array 12 may operate as an alphanumerical display, such that it can be used to display current information regarding distance, type of ammunition, etc.
[0050] FIG. 3 is a block diagram illustrating the processing section of the inventive sight. The block-diagram is a simplified diagram with the purpose of illustrating the operations of the sight 1 . In use, data relating to a distance to a target and other optional inputs are transferred to the processor, which uses them in combination with relevant data from the memory to calculate the correct reticle. A control signal for controlling the array 12 is output from the processor, and the array 12 starts emitting light from a specific location (one or several) as a result.
[0051] The list in input section of FIG. 3 is extensive, and yet non-exhaustive. There are numerous of inputs that may be used for aiding in using the sight, whereof the type of ammunition and the distance to the target are two important inputs. One advantage of the present sight is that its construction allows it to be versatile, and basically any information affecting the trajectory of the ammunition used, or other parameters relevant for the user, may be used by the processor/microcontroller or displayed to the user. This information may also be communicated from the sight to other external units.
[0052] The distance to the target is generally measured with the rangefinder, but could also be input by the user, or by the sight receiving information by other means. The same is true for the type of ammunition, which either is detected automatically or input by the user.
[0053] The memory contains all information needed to control the sight. Such as tables and algorithms related to ammunition properties. The memory may communicate with external units such as to allow for updates, etc.
[0054] Examples of input variables include, but is not limited to: Ammunition data, type of ammunition, ammunition properties (trajectories coupled to distance, wind speed etc.); Target data, distance, relative altitude, velocity, geographical coordinates; Environmental data, air speed, air temperature, geographical coordinates; Weapon data, inclination, velocity, atmospheric pressure, wind speed, geographical coordinates; User settings, manual inputs, corrections
[0055] FIGS. 4 and 5 are perspective views of the fire-control system according to one embodiment. By comparison with corresponding reference numbers in FIG. 1 the alignment of the views of FIGS. 4 and 5 , respectively, are self-explanatory.
[0056] Apart from what has already been described, FIG. 4 illustrates a housing 20 . The housing 20 seals and protects the interior from water and impacts. The housing needs to be rigid and durable. In one embodiment it is made of extruded, high strength aluminum, which is anodized, providing a strong, rigid and durable housing with a low weight. There are other alternatives for the housing too, such as reinforced plastics or composite materials. The housing 20 has contact surfaces to other components, such as protection windows 2 , 10 etc, and the choice of material is preferably such that the housing and related components have similar properties in relation to heat expansion. If not, it will be difficult to achieve a sight having adequate properties, and the choice of material may be made freely within the boundaries of that the sight preferably fulfills a harsh specification related to temperature, moisture etc. A lower portion of the housing 20 , which portion may be a separate part attached to the housing, contains a power source in the form of a battery pack. This portion may also comprise a control device 22 for regulating the intensity of the light emitted by the array 12 . The actual control of the RCLED intensity may be performed by varying pulse length to the RCLED in such a way that the human eye interprets it like a variation in intensity. This control method is thoroughly described in the application EP 1 210 561 A by the present applicant and will not be described in any further detail here, though the relevant details of said application are incorporated by reference. Also adjusting the current in the pulses can be used to increase the range in which the intensity can be set. This is specially important when using NVD.
[0057] A key pad 24 may be used as an interface between the sight and the user. The key pad 24 has a conventional functionality and is connected to control electronics of the sight in a conventional manner.
[0058] Further, mounts 30 for mounting the sight to a weapon are shown. Connections to remote control devices are preferable wireless, using e.g. suitable means for wireless communication. The use of wireless connections simplifies the task keeping the interior of the fire-control system protected from the outside environment (moist, dust, gases). If physical connectors are desired they may be arranged for at a suitable position, e.g. for a remote control and charging/communication/auxiliary devices. The remote control may be used to simplify input during shooting, such that the user can aim at a target having the correct shooting position and input data at the same time. The remote control could have a design similar to the keypad 24 , or have a simplified design, comprising e.g. buttons for using the rangefinder and correcting the reticle only. FIG. 4 also illustrates the intensity knob 22 , which is a rotary switch used in order to adjust the intensity of the reticle. Auxiliary devices include a keyboard, a GNSS receiver, a gyro device, an inclinometer, device for communication with the ammunition and/or any other element performing functions as demonstrated above with reference to FIG. 3 . The auxiliary devices, or other types of external information, may communicate with the sight via a wire or via wireless communication, as discussed above. Wireless communication can also occur between the ammunition and the sight, such as information related to timing of the ammunition. Some or all of these devices may also be incorporated into the actual fire-control device. The connections may also be used for downloading new processing software and ammunition tables/algorithms etc.
[0059] FIG. 5 shows the fire-control system in a perspective view from a direction such that the output lens 36 and the receiving lens, 38 of the rangefinder 18 are visible. Opposite to the intensity knob 22 , the battery cap 40 is shown. For ease of maintenance the sight preferably uses standard AA batteries, available all over the world, as energy source. Of course rechargeable AA batteries as well as Lithium batteries can be used.
[0060] FIG. 6 illustrates a recoilless grenade weapon provided onto which the inventive fire-control system may be mounted, on the mount 42 . The fire-control system may then be connected to a control device, arranged on front handle 44 of the weapon. Three control buttons 46 , 48 , 50 are arranged within reach of a users thumb while gripping the front handle 44 . The communication between the control device on the front handle 44 and the fire-control system is preferably wireless, e.g. via a Texas Instruments CC2500 low power transceiver.
[0061] When using the sight the user has to switch it on and, if it is used for a new purpose, initiate it by setting some user parameters, such as the type of ammunition used, various offsets etc. When looking in the sight and pushing the LRF (Laser Range Finder) knob the user will then see a static illuminated reticle, which is used to direct the rangefinder onto a target and zeroed with the rangefinder. When the static illuminated reticle is superimposed over the target the rangefinder may be activated, e.g. by releasing the knob. This action results in that the distance to the target is measured and can be displayed by the alphanumerical display. It can also result in that a second reticle, e.g. with pulsating intensity, is displayed to the user. The user may then have the opportunity to adjust the position of the second reticle in order to compensate for target movement, wind etc, before superimposing the second reticle over the target and firing the weapon, if any of these parameters is not compensated for by the fire-control system. After firing the weapon the position of the second reticle may be adjusted yet again. The second reticle may differ visually from the first, if displayed at the same time, in order to avoid confusion. The skilled person realizes that this can be achieved in several different ways.
[0062] Correction of the position of the reticle as a response to the inclination of the weapon will be described next. In order to achieve such a correction the sight, or the weapon, has to be provided with a sensor for measuring inclination, e.g. an inclinometer from Freescale Semiconductor. If the distance to the target was the only parameter to be considered the inclination in the length direction of the weapon would be accounted for in the initial target acquisition, i.e. by measuring the distance to the target. Another parameter that has to be accounted for, however, occurs when firing at a target being positioned at a lower or higher altitude than the weapon itself. Provided that the weapon receives information regarding difference in altitude this inclination too is accounted for when performing the initial acquisition of the target. This may be achieved by combining the information from the distance measurement with information from an inclinometer, detecting the inclination in the length direction of the weapon. The information may also be acquired from other sources. An inclination, or tilt, in the cross direction of the weapon may occur when the user is tilting the weapon by mistake. The tilt is less predictable than the inclination in the length direction, since it may be altered between the acquisition of the target and the actual moment of firing the weapon, and it is self explanatory how the tilt may cause a significant miss of the target. One way of eliminating the problem of tilt may be to introduce a virtual horizon, or other indication of how the weapon should be tilted in order to reach a horizontal position in the cross direction. According to another embodiment of the present invention, however, the CPU rapidly determines, by analyzing a signal from the inclination sensors, the tilt of the weapon, after which the position of the reticle is adjusted accordingly. One beneficial effect of the latter technique is that the information displayed to the user may be kept at a minimum, shortening the time between target acquisition and the first shot fired at the target. If the tilt of the weapon is too large, so that the adjusted position of the reticle is outside of the capacity of the array, the system may be adapted to provide an indication regarding how the weapon should be tilted back. One example of such an indication may be a twinkling arrow, or other shape that may not be confused with the reticle.
[0063] The method according to the present invention, as illustrated in the drawings is suitable for implementation with aid of processing means, such as computers and/or processors. Therefore, there is provided a computer program comprising instructions arranged to cause the processing means, processor, or computer to perform the steps of the method according to any of the embodiments described or the method necessary to make the fire-control system according to any embodiment described operate in the desired manner. The steps are preferably performed by the processing means, processor, or computer in cooperation with physical means, such as those described with reference to any of the disclosed embodiments, with aid of e.g. an illumination control circuit powering the light source(s) of the array. The computer program preferably comprises program code, as illustrated in FIG. 8 , which is stored on a computer readable medium 602 , which can be loaded and executed by a processing means, processor, or computer 604 to cause it to perform the method according to the present invention, preferably as any of the exemplary embodiments described with reference to the drawings. The computer program can for example cause the processor to correct calculated trajectories to account for windage etc, or the compensated position for the reticle resulting from a tilt of the fire-control system.
[0064] The computer and computer program can be arranged to execute the program code sequentially where actions of the any of the methods are performed stepwise, or be arranged to execute the program code on a real-time basis where actions of any of the methods are performed upon need and availability of data. The processing means, processor, or computer is preferably what normally is referred to as an embedded system. Thus, the depicted computer readable medium 602 and computer 604 in FIG. 8 should be construed to be for illustrative purposes only to provide understanding of the principle, and not to be construed as any direct illustration of the elements.
[0065] The present invention is particularly well suited for weapons firing ammunition with a high trajectory, such as an underslung grenade launcher (UGL), automatic grenade launcher (AGL), recoilless grenade rifle (such as the Carl Gustaf), etc, and may to the full extent be used on such a weapon. | A fire-control system comprising -a housing, -a light channel, through which a user may directly observe a target and receive visually displayed information simultaneously, said light channel comprising partially reflective optics a light source, for visualization of a reticle to the user via the partially reflective optics, -means for receiving a measure of the distance to the target a processor, for determining the adequate position of the reticle, based on the distance to the target, and for controlling the light source to emit light so that the reticle is visualized at the adequate position, wherein the light source is an array capable of selectively emitting light in well defined locations on its surface. | 5 |
TITLE OF THE INVENTION
1. Background of the Invention
The invention relates to a system of automatic connection of two electrical circuits of a vehicle, and more precisely a system for automatic connection of a principal electric circuit of the vehicle to an auxiliary electrical circuit of a sub-assembly, such as a seat, of the vehicle.
2. Description of the Related Art
U.S. Pat. No. 5,752,845 describes an arrangement in which the sub-assembly is mounted on a structural element of the vehicle in a substantially vertical mounting direction, an auxiliary element of the electrical connector, fixed on the sub-assembly, being coupled to a principal electrical connector element carried by the principal electrical element carried by the structural element. The principal electrical connector element is movable relative to the structural element, between a rest position toward which it is resiliently urged, and a connection position toward which it is moved automatically by the sub-assembly.
EP 1 135 833 describes an arrangement of the same type in which the principal electrical connector element is swingably mounted relative to the structural element of the vehicle, about a horizontal swinging axis, the auxiliary electrical connector element carrying a control tongue to swing the principal connector element from its rest position toward its connection position.
Because the principal electrical connector element is swingably mounted about a horizontal swinging axis, it is necessary, in order to ensure the taking up of the play at the time of connection, to use an intermediate guided plate, urged by several springs acting in different directions. The principal connector element is mounted on this intermediate plate and is urged toward its rest position by another spring.
The arrangement thus described is complicated, it comprises a high number of pieces to be assembled and several springs; it is accordingly sensitive to assemble and to use.
SUMMARY OF THE INVENTION
An object of the present invention is to avoid the complexity of the known arrangements and to propose a connection system that is simple and easy to use, whilst being reliable.
Another object of the present invention is to propose a connection system without interaction with the support structure of the connection.
The invention has for its object an automatic connection system of a principal electrical circuit of a vehicle to an auxiliary electrical circuit of a sub-assembly such as a seat of the vehicle, movable for its securement to a structural element of the vehicle in a substantially vertical mounting direction, said system comprising an auxiliary contact carrier, fixed on the sub-assembly, and a principal contact carrier movable on the structural element, between a rest position toward which it is resiliently urged and a connection position toward which it is automatically moved by the auxiliary contact carrier during mounting of the sub-assembly on the structural element of the vehicle, the connection between the principal contact carrier and the auxiliary contact carrier being ensured in a substantially vertical plane, characterized in that: the principal contact carrier is swingably mounted in a support of the structural element, bearing on a spring, and comprises projecting members to ensure the guidance of the auxiliary contact carrier during the connection movement.
According to other characteristics:
the projecting members comprise protuberances disposed on the lateral surfaces of the principal contact carrier and adapted to guide the lateral surfaces of the auxiliary contact carrier; the protuberances have a rear profile adapted to coact with a ramp carried by the auxiliary contact carrier; the principal contact carrier has on its front surface a lower lip adapted to coact with the lower portion of the auxiliary contact carrier; the principal contact carrier has on its front surface an upper lip adapted to coact with a ridge of the auxiliary contact carrier; the principal contact carrier has an actuating finger for an actuator carried by the auxiliary contact carrier to ensure the deshunting of the auxiliary contacts at the end of connection; the spring has one end fixed to the support, its other end being free, and it is bent in a curve below the principal contact carrier.
According to a particular embodiment of the invention, said principal contact carrier and said auxiliary contact carrier each comprise a protection means covering their respective contact elements, each of said protection means comprising a conductive portion, each of said protection means being movable between an inactive position in which said conductive portion is not in contact with said corresponding contact element and an active position in which said conductive portion is in contact with said corresponding contact elements, said protection means being adapted to assume automatically said active position when said principal contact carrier is moved to said connection position, said conductive portions of each of said protection means being in contact when said protection means are in said active position.
Preferably, each of said protection means comprises a flexible membrane, said membrane being fixed in a sealed relation to a flange surrounding said contact elements, said conductive portion comprising metallic lugs passing through said membrane.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics will become apparent from the description which follows given with reference to the accompanying drawings, in which:
FIG. 1 is a fragmentary axial cross-sectional view of the automatic connection system according to one embodiment of the invention, at the beginning of the descending movement of the auxiliary contact carrier,
FIG. 2 is a fragmentary axial cross-sectional view of the connection system of FIG. 1 at the time of entry into mechanical contact of the auxiliary contact carrier with the principal contact carrier,
FIG. 3 is a fragmentary axial cross-sectional view of the connection system of FIG. 1 at the time of entry into electrical contact of the contacts of the lower row of the auxiliary and principal contact carriers,
FIG. 4 is a fragmentary axial cross-sectional view of the connection system of FIG. 1 after completion of connection,
FIG. 5 is an enlarged cross-sectional view of the contacts of FIG. 3 ,
FIG. 6 is an enlarged cross-sectional view of the contacts of the upper row after their entry into contact,
FIG. 7 is an enlarged cross-sectional view of the contacts of FIG. 6 before deshunting,
FIG. 8 is an enlarged cross-sectional view of the contacts of FIG. 7 after deshunting, which is to say in the condition of FIG. 4 ,
FIG. 9 is a view similar to FIG. 1 showing a second embodiment of the invention, and
FIG. 10 is a fragmentary axial cross-sectional view of the connection system of FIG. 9 after completion of connection.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 , a support 1 secured to the floor of the vehicle constitutes a sort of housing open at its upper portion, having a rear partition and a front partition 3 between which will move on the one hand the principal contact carrier 4 , on the other hand the auxiliary contact carrier 5 .
The support 1 comprises two lateral partitions, parallel to the plane of the sheet, each having a vertical slideway upwardly open like a funnel, adapted to receive, freely slidably, a finger carried laterally by the principal contact carrier 4 , substantially at its base and forwardly. The principal contact carrier is thus guided during its insertion into the support 1 .
At the bottom of the support 1 is disposed a spring 6 in the form of a blade, whose forward end 7 is rigidly fixed to the front of the base of the support 1 . The blade is bent upwardly to be offset from the bottom of the support 1 , then bent in a rounded shape toward the base below the principal contact carrier and its other end 8 or rear end is free and elbowed below the base of the support 1 , by passing through an opening of the base of the support 1 through which it can pass in the case of pressure on its rounded portion.
On their upper edge, the partitions of the support 1 have chamfers such as 9 to guide the principal contact carrier 4 during its emplacement in the support 1 , and the auxiliary contact carrier 5 during its descending movement.
The principal contact carrier 4 is in the general shape of a rectangular parallelepipedal. Its rear surface 10 is, in the rest position, bearing against the rear partition 2 of the support 1 . This forward surface 11 lets pass the electrical contacts distributed in a lower row 12 and an upper row 13 in the illustrated embodiment, without the number of these rows being limiting. The lower surface 14 of the principal contact carrier 4 is prolonged forwardly by a lower oblique lip 15 .
The upper surface 16 of the principal contact carrier 4 is prolonged forwardly by an upper oblique lip 17 . The lips 15 and 17 diverge. The lateral surfaces of the principal contact carrier 4 bear protuberances such as 18 having forwardly a profile in the form of a horn directed upwardly.
In a manner known per se, the electrical contacts of the two rows 12 and 13 are connected at their rearward portion to a cable which is part of the electrical circuit of the vehicle and is not shown.
The auxiliary contact carrier 5 is in the form of a block having a forward portion and a rear portion. The forward portion comprises at its lower portion two rows of contacts adapted to be placed against the contacts of the principal contact carrier, and distributed respectively in a lower row 19 and an upper row 20 . These two rows of contacts are disposed in a parallepipedal volume corresponding substantially to the volume of the principal contact carrier 4 .
The forward surface 21 of the auxiliary contact carrier 5 is adapted to bear on the forward partition 3 of the support 1 . The rear portion of the auxiliary contact carrier 5 has lateral walls such as 22 of which the lower edge is provided at the rear with a chamfer 23 adapted to coact with the chamfer 9 of the rear partition 2 of the support 1 . At its upper portion, the rear portion of the auxiliary contact carrier 5 has a ridge 24 adapted to coact with the upper lip 17 of the principal contact carrier 4 .
In the rest position, the principal contact carrier 4 bears with its lower surface 14 on the rounded portion of the spring 6 , and with its rear surface against the rear partition 2 of the support 1 . It is in the rearwardly swung position, its forward surface 11 being slightly oriented upwardly.
The auxiliary contact carrier 5 , in its descending movement, is guided at the inlet of the support 1 by the chamfers 9 . The role of the chamfers 23 , in addition to aiding the insertion into the support 1 , is to move the auxiliary contact carrier 5 forwardly, its forward surface 21 entering into contact with the forward partition 3 of the support.
When the descending movement takes place ( FIG. 2 ), the lateral walls of the auxiliary contact carrier 5 are guided by the protuberances 18 of the principal contact carrier 4 , which ensures a centering of the auxiliary contact carrier 5 in the median plane of the support 1 . Then, the ridge 24 comes into contact with the upper lip 17 of the principal contact carrier 4 , and a ramp 25 of the lateral wall 22 of the auxiliary contact carrier 5 , comes into contact with the rear profile 26 of the protuberance 18 of the principal contact carrier 4 .
When the descending movement takes place ( FIG. 3 ), on the one hand the lower front portion of the auxiliary contact carrier 5 comes to bear against the lower lip 15 , on the other hand the ridge 24 slides on the upper lip 17 , which gives rise to forward swinging of the principal contact carrier 4 which pivots on the rounded portion of the spring 6 . The ramp 25 slides on the rear profile 26 and causes rearward movement of the auxiliary contact carrier, which retreats until its lateral walls 22 come to bear against the rear partition 2 of the support 1 . In the course of this combined movement the electrical contacts of the lower rows 12 and 19 respectively of the principal and auxiliary contact carriers come into contact with each other.
Moreover, in the median portion of the principal and auxiliary contact carriers 4 and 5 there is provided a mechanical connection between a crosspiece 27 of the principal contact carrier and a hook 28 of the auxiliary contact carrier. Finally, the pressure applied to the principal contact carrier 4 is exerted on the spring 6 whose rear end 8 is moved away from bearing relation with the bottom of the support 1 .
When the descending movement is completed ( FIG. 4 ), the pivoting of the principal contact carrier 4 is terminated: its forward surface is substantially vertical; the contacts of the two upper and lower rows 12 , 19 and 13 , 20 bear against each other respectively; the ramp 25 bears stably against the rear profile 26 of the protuberance 18 ; the hook 28 is hooked stably to the crosspiece 27 ; the spring 6 is urged downwardly and its end 8 is substantially separated from the bottom of the support 1 ; the pressure of the spring 6 upwardly ensures the stable maintenance of the connection between the various electrical contacts. The over-movement of the spring 6 permits taking up the vertical movement at the end of the connection movement.
FIG. 5 is an enlarged view of the electrical contacts of the lower rows 12 , 19 at the time of their entry into contact. The principal contact 29 of the lower row 12 and the auxiliary contact 30 of the lower row 19 are vertically offset. An equipotential shunt 31 is shown, in electrical contact with the auxiliary contact 30 .
In FIG. 6 , the principal and auxiliary contacts 29 and 30 face each other, after relative movement which has the effect of cleaning the electrical contacts. Similarly, the respective contacts 32 and 33 of the upper rows 13 and 20 are in contact.
In FIG. 7 , the shunt 31 begins its retraction forwardly and arrives in abutment against the insulating wall. In FIG. 8 , the retracting movement of the shunt 31 is ended, the shunt being insulated from the electrical contacts by the insulating wall 34 . This retraction movement of the shunt is ensured by an actuator carried by the auxiliary contact carrier 5 which is pressed by an actuating figure of the principal contact carrier 4 . At the end of the connection, the electrical contacts are in compression.
The automatic connection system according to the invention ensures the connection without interaction with the structural elements which support the connection elements.
The auxiliary contact carrier ensures taking up the play in the horizontal plane perpendicular to the connection movement. The principal contact carrier is swingably mounted and serves to guide the auxiliary contact carrier thanks to its projecting elements: upper and lower lips, protuberances with their rear profile.
The support with a single spring permits ensuring the holding in the rest position of the principal contact carrier, and at the end of connection, ensures taking up the play in the vertical direction of the connection movement, and the locking in connected position.
The connection movement combines a descent of the auxiliary contact carrier and a swinging of the principal contact carrier. In the course of this movement, there takes place a cleaning of the electrical contacts.
The actuator ensuring the deshunting is preferably constituted by a drawer moved, at the end of connection, by a finger carried by the principal contact carrier.
This drawer movement can be used to control other functions.
In the course of the connection movement, the principal contact carrier pivots on the rounded portion of the spring, and the spring does not maintain the same position: as a result, the principal contact carrier does not pivot relative to a fixed axis.
Referring to FIGS. 9 and 10 , there will now be described a second embodiment. The elements of the connection system identical or similar to the first embodiment are shown by the same reference numeral increased by 100 and are not described again. Here, the contacts of the principal contact carrier 104 are distributed in a single row 112 , this number not being limiting. The auxiliary contact carrier 105 also comprises a single row of contacts 119 .
The contact carrier 104 comprises on its forward surface 111 a flange 140 surrounding the row 112 . The flange 140 comprises on its lower surface 140 a a peripheral groove 141 . A flexible membrane 142 , for example of elastomer, is inserted in the groove 141 , such that the connection between the groove 141 and the membrane 142 will be sealed. The massive metallic lugs 143 , disposed respectively in line with each contact of row 112 , pass through the membrane 142 and are fixed to the membrane 142 in a sealed manner. The lugs 143 have for example a substantially cylindrical shape and project on opposite sides of the membrane 142 . In the rest position ( FIG. 9 ), the membrane 142 extends in the plane of the groove 141 , the contacts of the row 112 and the lugs 143 being separated by a distance d, the distance d being preferably greater than 0.5 mm.
The contact carrier 105 has in a similar manner a flange 150 surrounding the row 119 . The flange 150 comprises on its lower surface 150 a a peripheral groove 151 . A flexible member 152 , for example of elastomer, is inserted in the groove 151 , such that the connection between the groove 151 and the membrane 152 will be sealed. The massive metallic lugs 153 , disposed respectively in line with each contact of the row 119 , pass through the membrane 152 and are fixed in a sealed manner to the membrane 152 . The lugs 153 have for example a substantially cylindrical shape and project on opposite sides of the membrane 152 . In the rest position ( FIG. 9 ), the membrane 152 extends in the plane of the groove 151 , the contacts of the row 119 and the lugs 153 being separated by a distance h, the distance h being for example equal to the distance d.
In the rest position, the principal contact carrier 104 is in rearwardly swung position, its forward surface 111 slightly upwardly oriented, such as has been previously described. The membranes 142 and 152 are flat and the lugs 143 and 153 are separated from the contacts of the row 112 and the row 119 , respectively.
The descending movement is similar to the first embodiment. During this movement, the lugs 143 and 153 , which face each other, come into contact.
During the course of the descent, the pressure exerted by the lugs 143 and 153 against each other causes the deformation of the membranes 142 , 152 . The depth of the flanges 140 , 150 and the length of the projecting portions of the lugs 143 , 153 are provided so as to permit a sufficient deformation of the membranes 142 , 152 , such that, when the descent takes place, the lugs 143 , 153 will be adapted to come into contact against the contacts of the rows 112 , 119 and compress the spring integrated with these contacts.
In the connected position, the contacts of the row 112 are in contact with the lugs 143 , the lugs 143 are in contact with the lugs 153 and the lugs 153 are in contact with the contacts of the row 119 . The current can thus flow between the contact carrier 104 and the contact carrier 105 . This position is shown in FIG. 10 .
Thus, the membranes 142 , 152 permit protecting the contacts of the rows 112 , 119 against any flow, particularly of water, adapted to degrade their mechanical and/or electrical qualities. Moreover, even if the contacts of the rows 112 , 119 remain powered when the contact carriers 104 , 105 are in rest position, the metallic lugs 143 , 153 , which are spaced from the contacts by the membranes 142 , 152 , are not supplied, which increases the safety of the connection system. | The inventive system for automatically connecting the main electric circuit of a vehicle to the auxiliary circuit of a subset like a seat comprises an auxiliary contact carrier ( 5 ) fixed to said subset and a main contact carrier ( 4 ) which is movable along a structural element. Said main contact carrier ( 4 ) is oscillatingly mounted on the support ( 1 ) of a structural element in such a way that it is supported by a spring ( 6 ) and is provided with protruding members for guiding the auxiliary contact carrier ( 5 ) during a connecting movement. | 7 |
REFERENCE TO PRIOR APPLICATION
This application is a continuation of U.S. patent application Ser. No. 07/177,553 filed Apr. 1, 1988 for "Combination Sanitaryware And Fitting", now abandoned.
BACKGROUND OF THE DISCLOSURE
1. Field of the Invention
The invention concerns an integrated plumbing fixture and fitting having a spout that is straight or curved in its cross section and which provides relatively wide, film-like water jets in the form of a waterfall.
2. Description of Prior Art
Previously known waterfall-type spouts are formed having a cross section that remains uniform in the flow direction. The disadvantage of such a design is that the water jet is constricted after leaving its outlet so that its surface tension tends to return the water jet to a cylindrical jet. The results of such previous designs are that film-like water jets produced are unsatisfactory.
With the usual bathroom arrangements, the sink or the bathtub and the sanitary fitting are separated from one another, where the spout either is fastened to a wall or is fastened on the sink or on a section of the bathtub and therefore protrudes from it. For some time, a possibility has been sought to avoid such a protruding outlet.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a bathtub or sink arrangement having an integrated sanitary fitting where its water outlet, spout, does not protrude and is generally not visible when viewing the bathtub or sink.
Another object of the invention is to provide a spout which has a cross section that increases in width in the direction of water flow, thereby preventing constriction of the film-like water jets.
Still another object of the invention is to provide a spout in which the cross section spout decreases in height in the flow direction so that the flow rate of water through the spout remains constant despite the increase in width of the spout in the direction of flow.
A further object of the invention is to overcome the disadvantages heretofore encountered and to provide a spout of the waterfall type, which is inexpensive to manufacture and which has a very simple structure.
The invention generally contemplates providing, in bathtubs, sinks or the like, a water outlet or spout which is integrated with a sanitary fitting. Also, the water spout is designed to discharge water in waterfall-like fashion. The water discharged from a wall of the sanitaryware, such as a bathtub, sink or the like, is generally in the form of a straight or curved curtain or a filmy gush, and is distributed over a wide area at the bottom of the sanitaryware. Further, such a spout arrangement is space-saving since the integrated water spout is designed generally flat according to the type of waterfall spout of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail, by way of example, in terms of the drawings:
FIG. 1 is a perspective view of an integrated lavatory and sanitary fitting illustrating the waterfall pattern discharged from the spout, in accordance with the present invention;
FIG. 2 is a perspective view of the sanitaryware only;
FIG. 3 is a perspective view of the sanitary fitting only;
FIG. 4 is a sectional view, in elevation, taken along the lines 4--4 of FIG. 1;
FIG. 5 is a fragmentary sectional view, in elevation, taken along the lines 5--5 of FIG. 1;
FIG. 6 is a front elevational view of the sanitary fitting with the sanitaryware broken away; and
FIG. 7 is a top plan view of the sanitary fitting with portions thereof broken away.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a perspective view illustrating an integrated sanitary fitting 3 mounted to a lavatory 2. The mixture and the volume of water flow are regulated by handle 4 of sanitary fitting 3, shown in FIG. 3. FIG. 4 is a sectional view, in elevation, of sanitary fitting 3, including a spout 1 which is housed in recess 16 of wall 15 of lavatory 2. Spout 1 extends through opening 24, and is connected to tubular jacket 14. Tubular jacket 14 surrounds a distributor tube 7, whose outlet openings generally shown at 21 are situated in the lower area of tubular jacket 14 and are directed against it Distributor tube 7 is surrounded by a screen 20 so that at least some water discharging from distributor tube 7 passes through screen. 20 twice by first being forced downward through screen 20 and then upward through screen 20 again towards spout 1. A longitudinal slot 19 connects with the upper area of tubular jacket 14. The water then flows out from longitudinal slot 19 in a waterfall-like fashion.
Sanitary fitting 3 can best be seen in FIGS. 4-6. The water supply is coupled to connecting tubes 6, to which hoses or conduits 5 are connected. Hoses 5 lead to sanitary fitting 3, which has a handle 4 and a housing 11. A valve cartridge 12, such as is shown in U.S. Pat. No. 3,433,264 of Parkison, with valving elements for mixing hot and cold water, is mounted in housing 11 of sanitary fitting 3.
Valving elements of valve cartridge 12 can have two ceramic discs, one of which is fixed and the other one movable. One disc includes ports for the inflow of cold and hot water and the outflow of mixed water, with the other disc having a mixing chamber. A rosette 10 and O-rings 17,18 are provided in the usual manner between operating lever 4 and housing 11. Also, shown in FIG. 6, is a securing nut 13 which mounts sanitary fitting 3 to lavatory 2. A connecting tube 25 is coupled to the water outlet of housing 11. Connecting tube 25 is coupled to distributor tube 7. At the transition between connecting tube 25 and distributor tube 7, the mixed water flows through a flow restrictor 8 and a filter or screen 9. Distributor tube 7 is coupled to waterfall spout 1 by adjustable jacket 14.
Distributor tube 7 is formed having a plurality of holes 21 for discharging mixed water therefrom. Since distributor tube 7 is surrounded by screen 20, the high flow rate of water is reduced Also, since distributor tube 7 is situated in the lower area of jacket 14 any air that may be present in the lower area of jacket 14 will be forced out of spout 1 and water discharged from spout 1 is non-turbulent.
Various inserts can be placed into waterfall spout 1. These facilitate an adaptation to the particular water quantities (bathtub or sink) by different slot heights which decrease in the flow direction, but they do not change the pattern of the jet. One possible waterflow for a slot height at the outlet end of spout 1, for example, may be 1.8 mm and at the opposite end of spout 1, 5.5 mm. Because of the decrease of the slot height, the flow rate remains constant.
The edges of waterfall spout 1 can be inclined at an angle, a=30° (FIG. 7), resulting in an opening angle of the waterfall spout ranging from 60° to 70°. Because the forward edge 23 of spout 1 preferably has a circular curvature, it is guaranteed that the gush of water rises in the middle and then propagates from there towards the ends. For example, a radius of about 80 mm at the outlet with a simultaneous downward slant of the outlet slot by about β=15° (FIG. 4) prevents a backflow below the nozzle to the feed line. When small amounts of water are withdrawn, the run-out jets will migrate towards the middle of the slot.
It is possible to fabricate practically all parts from a suitable plastic material Further, it is possible to install a light source in the outlet slot or near the forward edge 23 so that the gush of water entering the basin of lavatory 2 is illuminated. The longitudinal slot 19 can be designed so that its walls are inclined to one another at an angle of about 5°. It is also possible for the walls, as shown in FIG. 4, to be initially inclined more towards one another and, then, in the last region, to be only slightly inclined to one another or to run even parallel. | A sanitary fitting and plumbing fixture, such as a sink, bathtub or lavatory, are so arranged such that the actuating lever and spout are disposed in recesses formed in the plumbing fitting, the spout being constructed so that when water is flowing through the fitting, it is discharged from the spout in a waterfall-like fashion. | 4 |
This application is a division of application Ser. No. 937,341 filed Dec. 3, 1986 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a high strength poly-m-phenylene isophthalamide fiber and a process for producing the same. More particularly, the present invention relates to a new type of poly-m-phenylene isophthalamide fiber having a much higher tensile strength than that of conventional poly-m-phenylene isophthalamide fibers, and a new process for producing the same.
2. Description of the Related Art
It is well known from, for example, U.S. Pat. Nos. 3,287,324, 3,300,450, 3,560,137 and 4,073,837, that conventional poly-m-phenylene isophthalamide fibers, which are available under a registered trademark of TEIJINCONEX or NOMEX, exhibit an excellent heat-resistance and a superior flame-resistance, and are utilized in various fields, for example, clothing and industrial materials.
It is also known, however, that the conventional poly-m-phenylene isophthalamide fibers have a relatively low mechanical strength, for example, a tensile strength of about 5.5 g/denier or less, and therefore, utilization of the fibers is restricted in specific fields in which the fibers are required to exhibit a very high mechanical strength, for example, reinforcing fibrous materials for rubber products and synthetic resinous products, and substrate cloth for bag filter felts.
To eliminate the disadvantages of the conventional poly-m-phenylene isophthalamide fibers, poly-p-phenylene terephthalamide fibers are provided. The poly-p-phenylene terephthalamide fibers exhibit a very high mechanical strength, for example a tensile strength of about 20 g/denier or more. These poly-p-phenylene terephthalate fibers, however, can be produced only at a very high cost, and exhibit a very small ultimate elongation of about 5% or less. Accordingly, the poly-p-phenylene terephthalamide fibers are not usable in fields in which the fibers are required to have an ultimate elongation of more than about 5%. Also, the poly-p-phenylene terephthalamide fibers are disadvantageous in that fibrillation thereof is easily caused.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a high strength poly-m-phenylene isophthalamide fiber having a higher tensile strength than that of conventional poly-m-phenylene isophthalamide fibers, that is, 6.5 g/denier or more, and a process for producing the same.
The above-mentioned object is attained by the high strength poly-m-phenylene isophthalamide fiber of the present invention and the process of the present invention for producing the above-mentioned fiber.
The high strength poly-m-phenylene isophthalamide fiber of the present invention comprises an m-phenylene isophthalamide polymer containing at least 95 molar % of recurring m-phenylene isophthalamide units and having an intrinsic viscosity ([η]) of from 0.7 to 2.5, determined at a concentration of 0.5 g/100 ml in dehydrated N-methyl-2-pyrrolidone at a temperature of 30° C., and has a birefringence of from 0.18 to 0.22, a degree of crystallinity of from 45% to 55%, a crystalline size of from 35 to 45 angstroms (Å), a tensile strength of 6.5 g/denier or more, and a silk factor of 35 or more.
The process of the present invention for producing a high strength poly-m-phenylene isophthalamide fiber having a birefringence of from 0.18 to 0.22, a degree of crystallinity of from 45% to 55%, a crystalline size of from 35 to 45 angstroms, a tensile strength of 6.5 g/denier or more, and a silk factor of 35 or more, comprises the operations of extruding a dope solution of an m-phenylene isophthalamide polymer containing at least 95 molar % of recurring m-phenylene isophthalate units and having an intrinsic viscosity ([η]) of from 0.7 to 2.5, determined at a concentration of 0.5 g/100 ml in dehydrated N-methyl-2-pyrrolidone at a temperature of 30° C., in an organic solvent through a spinneret having at least one spinning orifice, into a coagulating liquid to form at least one undrawn polymer filament; first adjusting the content of the organic solvent in the undrawn filament to a level of 15 to 30% based on the weight of the polymer in the filament; first wet drawing the first adjusted filament at a draw ratio of 1.1 to 1.5; second organic solvent content-adjusting the content of the organic solvent in the filament to a level of less than 15% based on the weight of the polymer in the filament; second wet drawing the second organic solvent content-adjusted filament at a draw ratio of 1.1 or more; drying the second wet drawn filament; and dry drawing the dried filament to an extent such that the entire draw ratio in the first and second wet drawing and dry drawing operations is in the range of from 4.0×7.0.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a flow sheet of an embodiment of the process of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the high strength poly-m-phenylene isophthalate fiber of the present invention, it is important that the fiber consists of a specific m-phenylene isophthalamide polymer containing 95 molar % or more of recurring m-phenylene isophthalamide units and having an intrinsic viscosity ([θ]) in a specific range of from 0.7 to 2.5, and exhibits a significantly enhanced molecular orientation represented by a birefringence of from 0.18 to 0.22, an increased degree of crystallinity of 45% to 55%, and a reduced crystalline size, compared with those of conventional poly-m-phenylene isophthalamide fibers.
The poly-m-phenylene isophthalamide fiber of the present invention preferably consists of a poly-m-phenylene isophthalamide alone. However, the m-phenylene isophthalamide polymer may consist of at least 95 molar %, preferably, at least 98 molar %, of recurring m-phenylene isophthalamide units and 5 molar % or less preferably 2 molar % or less of additional recurring units.
When the content of the additional recurring units is more than 5 molar %, the resultant fiber will exhibit an unsatisfactory degree of crystallinity and tensile strength.
The additional recurring units may contain an additional dicarboxyl acid component, for example, terephthalic acid, and an additional diamine component, for example, paraphenylenediamine or metaxylylenediamine.
The m-phenylene isophthalamide polymer usable for the present invention has an intrinsic viscosity ([η]) of 0.7 to 2.5, preferably, 1.2 to 2.0, determined at a concentration of 0.5 g/100 ml in N-methyl-2-pyrrolidone at a temperature of 30° C.
When the value of the intrinsic viscosity is less than 0.7, the resultant fiber will exhibit an unsatisfactory tensile strength even if the birefringence, degree of crystallinity, and crystalline size of the fiber are adjusted to the satisfactory values mentioned above. When the value of the intrinsic viscosity of the polymer is more than 2.5, the concentration of the polymer in the resultant spinning dope solution, which has an adequate viscosity and, thus, is usable for an ordinary wet spinning procedure, must be very small.
The polymer to be converted to the fiber of the present invention may contain one or more usual additives, for example, coloring matter, an ultraviolet ray-absorber, a light-stabilizer, and a flame-retardant.
The poly-m-phenylene isophthalamide fiber of the present invention exhibits a birefringence of from 0.18 to 0.22, preferably from 0.19 to 0.21, which represents a very high molecular orientation of the fiber; a degree of crystallinity of from 45% to 55%, preferably from 48% to 53%, which degree is remarkably higher than that of the conventional poly-m-phenylene isophthalamide fibers; and, a crystalline size of from 35 to 45 angstroms, preferably from 38 to 43 angstroms, which size is remarkably smaller than that of conventional poly-m-phenylene isophthalamide fibers.
When the birefringence is less than 0.18, the resultant fiber will have a poor degree of crystallinity of less than 48%, and thus an unsatisfactory mechanical strength.
If the refringence is more than 0.22, the resultant fiber will have an excessively high degree of crystallinity of more than 55%, and thus an undesirably low ultimate elongation and increased brittleness.
Also, if the degree of crystallinity is less than 45%, the resultant fiber will have an unsatisfactory mechanical strength. If the degree of crystallinity is more than 55%, the resultant fiber will exhibit an undesirably low ultimate elongation and increased brittleness.
Further, if the crystalline size is less than 35 Å, in the resultant fiber, the distinction between the crystalline regions and the amorphous regions will become unclear and the resultant fiber will exhibit a decreased dimensional stability. If the crystalline size is more than 45 Å, in the resultant fiber, the orientation of the crystals in the longitudinal direction of the fiber will be deteriorated and the resultant fiber will exhibit decreased physical properties.
In the poly-m-phenylene isophthalamide fiber of the presen invention, it was not expected that an impartment of the high orientation, the high crystallinity and the small crystalline size as specified above to the fiber would cause the resultant fiber to exhibit an enhanced tensile strength, which is about 20% higher than that of the conventional poly-m-phenylene isophthalamide fibers, without decreasing the ultimate elongation of the fiber.
Also, the inventors of the present invention have found through research that the poly-m-phenylene isophthalamide fiber of the present invention usually has a high degree of crystalline orientation of from 90% and 95%, which is considerably higher than that of the conventional poly-m-phenylene isophthalamide fibers.
The thickness and cross-sectional configuration of the poly-m-phenylene isophthalamide fiber of the present invention are not limited to a specific value and shape. But, the fiber of the present invention usually has a denier of from 1 to 10 and a regular round cross-sectional profile or an irregular, for example, elliptical, triangular, cocoon-shaped or hollow cross-sectional profile.
Due to the specific fine structure as mentioned above, the poly-m-phenylene isophthalamide fiber of the present invention has a high tensile strength of 6.5 g/denier or more, preferably 7.0 to 8.5 g/denier. In spite of the above-mentioned high tensile strength, the fiber of the present invention exhibits a preferable ultimate elongation of from about 20% to about 30%. Accordingly, the quantity of work necessary to break the fiber of the present invention by applying a tensile load thereto is larger than that of the conventional poly-m-phenylene isophthalate fibers. That is, a silk factor which represents the quantity of breaking work for the fiber of the present invention, is 35 or more.
Also, the poly-m-phenylene isophthalamide fiber of the present invention exhibits an excellent resistance to fibrillation thereof and is not fibrillated during use or processing, but conventional poly-p-phenylene terephthalamide fibers are easily fibrillated.
Furthermore, the poly-m-phenylene isophthalamide fiber of the present invention exhibits a superior heat resistance and, for example, a thermal shrinkage of 7% or less at a temperature of 300° C.
The poly-m-phenylene isophthalamide fiber of the present invention having the above-specified properties is produced by the process of the present invention. In this process, a dope solution of an m-phenylene isophthalamide polymer containing at least 95 molar % of recurring m-phenylene isophthalamide units and having an intrinsic viscosity of ([η]) 0.7 to 2.5, preferably, 1.2 to 2.0, determined at a concentration of 0.5 g/100 ml in dehydrated N-methyl-2-pyrrolidone at a temperature of 30° C. in an organic solvent, is extruded through a spinneret having at least one spinning orifice into a coagulating liquid. The resultant filamentary stream of the extruded dope solution comes into contact with the coagulating liquid and is coagulated therein to form undrawn polymer filaments.
Preferably, the dope solution is free from an inorganic salt, for example, calcium chloride. The presence of the inorganic salt in the dope solution means that the resultant filament must be washed under strict conditions, to completely remove the salt, and thus the filament-producing process becomes long and complicated.
The organic solvent usable for the dope solution preferably consists of at least one polar organic amide compound selected from the group consisting of N-methyl-2-pyrrolidone, N,N'-dimethylformamide and N,N'-dimethylacetamide.
The coagulating liquid usually consists of an aqueous solution of at least one inorganic salt, for example, calcium chloride, magnesium chloride or zinc chloride, and is used at a temperature of 60° C. to 100° C.
The wet spinning porcedure can be carried out under the conditions disclosed in detail in U.S. Pat. No. 4,073,837.
Referring to FIG. 1, the undrawn filament withdrawn from the coagulating liquid is subjected to a first solvent content-adjusting operation for adjusting the content of the organic solvent contained in the undrawn filament to a level of 15 to 30% based on the weight of the polymer in the filament. The first solvent content-adjusting operation may be carried out in a single step by using a single aqueous washing bath, or in two or more steps by using two or more aqueous washing baths.
The first solvent content-adjusted filament is subjected to a first wet drawing operation at a draw ratio of from 1.1 to 1.5. This first wet drawing operation can be carried out in a single step by using a single aqueous drawing bath, or in two or more steps by using two or more aqueous drawing baths.
The first wet drawn filament is subjected to a second solvent content-adjusting operation for adjusting the content of the organic solvent to a level of less than 15%, based on the weight of the polymer in the filament. This second solvent content-adjusting operation can be carried out in a single step by using a single aqueous washing bath, or in two or more steps by using two or more aqueous washing baths.
The second solvent content-adjusted filament is subjected to a second wet drawing operation at a draw ratio of 1.1 or more. This second wet drawing operation is carried out in a single step by using a single aqueous wet drawing bath, or in two or more steps by using two or more aqueous wet drawing baths.
The second wet drawn filament is dried and is then subjected to a dry drawing operation to an extent such that the entire draw ratio in the first and second wet drawing and dry drawing operations is in the range of from 4.0 to 7.0.
The dry drawn filament is subjected to a desired finishing operation, for example, winding up, heat-setting, or crimping.
In the first solvent content-adjusting operation, it is important that the content of the organic solvent contained in the undrawn filament be adjusted to a level of from 15% to 30% based on the weight of the polymer in the filament. When the content of the organic solvent is less than 15%, it will be difficult to satisfactorily draw the resultant filament in a washing water bath at a low temperature. Also, if the content of the organic solvent is more than 30%, the drawing procedure for the resultant filament will cause an undesirable flow of the molecules in the filament and, therefore, the degree of orientation of the molecules in the drawn filament will be poor.
The first solvent content-adjusting operation is usually carried out by bringing the undrawn filament into contact with at least one aqueous washing liquid containing 10% to 40% by weight of the same organic solvent as that contained in the dope solution, to adjust the content of the organic solvent in the filament to a desired level of from 15% to 30% and to control the crystallization rate and the crystal-growing rate of the filament. The first aqueous washing liquid preferably has a temperature of 20° C. to 70° C.
In the first wet drawing operation, the first solvent content-adjusted filament is drawn in at least one aqueous wet drawing bath while the content of the organic solvent remaining in the filament is reduced to a level of not less than 15% based on the weight of the polymer in the filament. In order to control the reducing rate of the organic solvent content in the filament, the first aqueous wet drawing bath contains the same organic solvent as that contained in the dope solution, and therefore in the filament, in a concentration of 3 to 30% by weight. Also, the temperature of the first wet drawing operation is preferably in the range of from 50° C. to 95° C., more preferably from 60° C. to 90° C. The first wet drawing operation is carried out in a single step, or in two or more steps so that the total draw ratio in the two or more drawing steps falls in a range of from 1.1 to 1.5.
If the total draw ratio is less than 1.1, the resultant drawn filament exhibits an unsatisfactory crystalline structure, molecular orientation, and tensile strength.
If the total draw ratio is more than 1.5, the resultant drawn filament will exhibit an undesirably low degree of orientation, because a flow of the molecules in the filament will preferentially occur in the drawing procedure.
In a preferable first wet drawing operation, the first solvent content-adjusted filament is drawn, in a first step, in a first aqueous wet drawing bath containing 10 to 30% by weight of the same organic solvent as that contained in the dope solution, and thus in the filament, at a draw ratio of 1.1 to 1.4 at a temperature of 50° C. to 70° C. and then, in a second step, in a second aqueous wet drawing bath containing the same organic solvent as that mentioned above in a concentration of 5% to 15% by weight but not more than that in the first aqueous wet drawing bath, at a draw ratio necessary to obtain the total draw ratio of 1.1 to 155, at a temperature of 70° C. to 90° C. It was confirmed that the first wet drawing operation can be smoothly carried out under the above-described conditions, and that the final filament having a satisfactory quality can be obtained from the resultant first drawn filament.
In the second solvent content-adjusting operation, the content of the organic filament in the first wet drawn filament is adjusted, in a single step or in two or more steps, to a level of less than 15% based on the weight of the polymer in the filament.
If the content of the organic solvent in the second solvent content-adjusted filament is more than 15%, the resultant filament from the second wet drawing procedure will exhibit an undesirably low degree of orientation and the crystallization of the filament in the next dry drawing procedure will be poor. The second solvent content-adjusting operation is carried out by bringing the first wet drawn filament into contact with at least one second aqueous washing liquid. The second aqueous washing liquid may consist of water alone or a small amount of an aqueous solution, for example, 10% by weight or less, of the same organic solvent as that contained in the dope solution or the filament.
The second aqueous washing liquid preferably has a temperature of 60° C. to 90° C.
The second solvent content-adjusted filament is subjected to a second wet drawing operation, which is carried out at a draw ratio of 1.1 or more, preferably 1.5 to 3.0 in at least one second aqueous wet drawing bath. The second wet drawing operation may be carried out while the organic solvent remaining in the filament is removed.
The one or more second aqueous drawing bath consists of water alone or an aqueous solution of the same organic solvent as that in the dope solution, and thus in the filament, at a concentration of 10% by weight or less. The second wet drawing operation is preferably carried out, in a single step or in two or more steps, at a temperature of 90° C. to 100° C. During the second wet drawing operation, a washing operation may be carried out at a temperature of 90° C. to 100° C. in at least one aqueous washing bath consisting of water alone.
Preferably, the second wet drawing operation is followed by a final washing operation in an aqueous washing bath consisting of water alone, to completely remove the organic solvent from the filament.
The second drawn filament or washed filament is dried by an ordinary method at a temperature of from 100° C. to 140° C.
The dried filament is subjected to a dry drawing operation to an extent such that the entire draw ratio in the first and second wet drawing and dry drawing operations falls within a range of from 4.0 to 7.0, preferably, 4.5 to 6.5. Preferably, the dry drawing operation is carried out at a temperature of 300° C. to 400° C. on a heating plate or in a heating oven, at a draw ratio of 1.5 to 2.5.
If the entire draw ratio is less than 4.0, the resultant filament will exhibit an unsatisfactory tensile strength of less than 6.5 g/denier. Also, if the entire draw ratio is more than 7.0, the drawing operations sometimes cause the filament to be ruptured.
The poly-m-phenylene isophthalamide fiber of the present invention has an excellent tensile strength of 6.5 g/denier or more, which is about 20% or more higher than that of conventional poly-m-phenylene isophthalamide fibers, a satisfactory ultimate elongation, and an excellent heat resistance. Therefore, the fiber of the present invention can be utilized for various fields, in which the conventional poly-m-phenylene isophthalamide fibers are not utilized due to the low tensile strength thereof, for example, reinforcing materials for rubber products and synthetic resin products, and substrate fabrics for bag filter felts.
Also, in some fields in which the conventional poly-m-phenylene isophthalamide fibers are utilized, the fibers of the present invention can be used in a reduced amount to produce a product having the same quality as that of the conventional fibers. That is, the fiber of the present invention is useful in that the products can be made lighter and smaller than the conventional products.
Furthermore, since the fiber of the present invention exhibits a higher initial tensile strength than that of the conventional fibers, and the same level of tensile strength-maintainability at a high temperature as that of the conventional fibers, a product, for example, a bag filter, made of the fiber of the present invention exhibits an enhanced durability during filtering operations.
The poly-m-phenylene isophthalamide fiber of the present invention is produced by the process of the present invention by stabilized procedures and at an improved efficiency.
The present invention will be further explained by way of specific examples, which, however, are representative and do not restrict the scope of the present invention in any way.
In the examples, the following tests were carried out.
(A) Intrinsic viscosity
The intrinsic viscosity of an m-phenylene isophthalamide polymer or fibers thereof was determined at a concentration of 0.5 g/100 ml in a solvent consisting of dehydrated N-methyl-2-pyrrolidone at a temperature of 30° C.
The intrinsic viscosity of the polymer is represented by [η], and that of the fibers is represented by [η] f .
(B) Degree of crystallinity
The degree of crystallinity of a fiber was determined by the standard X-ray diffraction method.
The calculation of crystalline regions and non-crystalline regions was carried out as follows.
(1) The value of the scattering angle, 2θ, was in the range of from 12° to 32°.
(2) A straight base line was drawn between 2θ=17° and 2θ=30°. A non-crystalline scattering curve for the non-crystalline regions consisted of the above-mentioned straight line and a meridional diffraction curve between 2θ<17° and 2θ>30°. The area (C) of the region between the non-crystalline scattering curve and a non-orientation approximate curve corresponded to a contribution of the crystalline regions. Also, the area (A) of the region between the non-crystalline scattering curve and an air scattering curve corresponds to a contribution of the non-crystalline regions.
The degree of crystallinity (%) is calculated in accordance with the following equation.
Degree of Crystallinity (%)=C/T(1-12.7/100)×100
wherein T=A+C.
(C) Crystalline size
The crystalline size was determined in accordance with the method for determining the apparent crystalline size (ACS) described in Japanese Examined Patent Publication (Kokoku) No. 61-3886, columns 12 to 13.
(D) Degree of crystalline orientation
This was determined by the standard simplified method with reference to Japanese Examined Patent Publication (Kokoku) No. 61-3886, columns 13 to 14. The poly-m-phenylene isophthalamide has a (110) reflection at 2θ=27.3° at the strongest peak point on an equator.
The degree of crystalline equation was calculated in accordance with the following equation.
Degree of crystalline orientation (%)=(180°-H°/180°)×100
wherein H represents a half value width.
(E) Tensile strength and ultimate elongation
Those items were determined in accordance with Japanese Industrial Standard (JIS) L-1015-1983, Test Method for Chemical Staple Fibers.
(F) Silk factor
This was determined in accordance with the following equation. ##EQU1## wherein S represents a tensile strength in g/denier and E represents an ultimate elongation in %.
EXAMPLE 1
An m-phenylene isophthalamide homopolymer produced in accordance with the interface polymerization method described in Japanese Examined Patent Publication (Kokoku) No. 47-10863, which corresponded to U.S. Pat. No. 3,640,970, and having an intrinsic viscosity [η] of 1.45 was dissolved at a concentration of 20.5% by weight in a solvent consisting of N-methyl-2-pyrrolidone, to provide a dope solution.
The dope solution was subjected to the wet spinning process described in Japanese Examined Patent Publication (Kokoku) No. 48-17551 in which a spinneret having 10,000 spinning orifices having a diameter of 0.07 mm and a coagulating liquid containing 45% by weight of calcium chloride dissolved in water and having a temperature of 90° C. were used.
The coagulated, undrawn filaments withdrawn from the coagulating liquid contained 45% of the solvent based on the weight of the polymer in the filaments.
The undrawn filaments were washed by a first solvent content-adjusting liquid containing 30% by weight of the solvent dissolved in water at a temperature of 30° C. to carry out a first adjustment of the content of the solvent in the filaments to a value of 25% based on the weight of the polymer in the filaments.
The first solvent content-adjusted filaments were subjected to a first wet drawing operation in two steps as shown in Table 1.
TABLE 1______________________________________First Wet Drawing Operation Step No.Item Step No. 1 Step No. 2______________________________________Aqueous wet Concentration of 20 10drawing bath solvent (% wt.) Temperature (°C.) 60 70Draw ratio 1.1 1.2______________________________________
The first wet drawn filaments were washed with water at a temperature of 50° C. to carry out a second adjustment of the content of the solvent remaining in the filaments to a level of 10% based on the weight of the polymer in the filaments.
The second solvent content-adjusted filaments were second wet drawn at a draw ratio of 2.1 in a wet drawing bath consisting of water at a temperature of 90° C.
The second wet drawn filaments were dried at a temperauure of 120° C. The dried filaments, which are substantially free from the solvent, were subjected to a dry drawing operation at a draw ratio of 1.7 at a temperature of 350° C. by means of a heat drawing plate.
The entire draw ratio was 4.7.
The results of the tests are shown in Table 2.
Comparative Example 1
The same procedures as those described in Example 1 were carried out with the following exception.
The poly-m-phenylene isophthalamide used had an intrinsic viscosity [η] of 1.35. The undrawn filaments were washed with water at a temperature of 60° C. to adjust the content of the solvent in the filaments to a value of 8%, and then were wet drawn at a draw ratio of 2.4 in a wet drawing bath consisting of water at a temperature of 95° C., were dried at a temperature of 130° C., and were finally dry drawn at a draw ratio of 1.75 in the same manner as that described in Example 1.
The test results are indicated in Table 2.
TABLE 2______________________________________ Example No. ComparativeItem Example 1 Examaple 1______________________________________Individual filament denier 2 2[η].sub.f 1.45 1.35Birefringence 0.190 0.152Degree of crystallinity (%) 50 41Crystalline size (Å) 42 48Degree of crystalline orientation (%) 92 89Tensile strength (g/d) 7.2 5.5Ultimate elongation (%) 30 37Silk factor 39.4 33.5Thermal shrinkage at 300° C. 5.5 5.5______________________________________
As Table 2 clearly indicates, the poly-m-phenylene isophthalamide fibers of Comparative Example 1, which fibers are similar to the conventional poly-m-phenylene isophthalamide fibers, had a tensile strength of 5.5 g/denier and a silk factor of 33.5, but the fibers of Example 1 in accordance with the present invention exhibited an excellent tensile strength of 7.2 g/denier and a superior silk factor of 39.4.
When the fibers of Example 1 were converted to a substrate cloth of a bag filter felt, it was found that the resultant bag filter had a higher durability than that of the conventional fibers.
EXAMPLE 2
A poly-m-phenylene isophthalamide having a intrinsic viscosity [η] of 1.35 was produced in accordance with the interface polymerization method described in Japanese Examined Patent Publication (Kokoku) No. 47-10863. The polymer was dissolved at a concentration of 22% by weight in a solvent consisting of N-methyl-2-pyrrolidone. The resultant dope solution was subjected to the wet-spinning process described in Japanese Examined Patent Publication (Kokoku) No. 48-17551 in which the spinneret had 6,000 spinning orifices having a diameter of 0.08 mm and the coagulating liquid contained 43% by weight of calcium chloride dissolved in water and had a temperature of 95° C.
The undrawn filaments contained 43% of the solvent based on the weight of the polymer in the filaments. The undrawn filaments were washed with an aqueous washing liquid containing 30% by weight of the solvent at a temperature of 40° C. to carry out a first adjustment of the content of the solvent in the filaments to a value of 23% by weight.
The first solvent content-adjusted filaments were first wet drawn in two steps under the conditions shown in Table 3.
TABLE 3______________________________________ Step No.Item Step No. 1 Step No. 2______________________________________Wet drawing Concentration of 10 7liquid solvent (%) Temperature (°C.) 45 60Draw ratio 1.1 1.2______________________________________
The first wet drawn filaments were washed with a washing liquid consisting of water alone to carry out a second adjustment of the content of the solvent remaining in the filament to a value of 12% by weight or less.
The second solvent content-adjusted filaments were second wet drawn in a wet drawing liquid consisting of water alone at a draw ratio of 2.2 at a temperature of 90° C.
The second wet drawn filaments were further washed with a washing liquid consisting of hot water alone at a temperature of 90° C., without drawing.
The washed filaments were dried at a temperature of 120° C., and then were dry drawn at a draw ratio of 1.70 by means of a heat drawing plate at a temperature of 355° C.
The entire draw ratio was 4.9.
The test results are indicated in Table 5.
EXAMPLES 3 TO 5 AND COMPARATIVE EXAMPLE 2
In each of Examples 3 to 5 and Comparative Example 2, the same procedures as those described in Example 2 were carried out except that the intrinsic viscosity [η] of the polymer used, the concentration of the polymer in the dope solution, and the concentrations of the solvent in the first and second washing baths were as shown in Table 4 and the first and second wet drawing operations and the dry drawing operation were carried out under the conditions shown in Table 4.
The test results are shown in Table 4.
TABLE 4__________________________________________________________________________ Example No. Example ComparativeItem 3 4 5 Example 2__________________________________________________________________________IV of polymer 1.30 1.40 1.35 1.35Concentration of polymer in dope solution (%) 22 21 22 22Content of solvent in first solvent content- 23 24 22 22adjusted filament (%)First wet drawing Step No. 1operation Temp. (°C.) 45 60 60 65 Conc. of solvent (%) 15 20 30 -- (CaCl.sub.2) Draw ratio 1.1 1.0* 1.1 1.0* Step No. 2 Temp. (°C.) 60 70 40 65 Conc. of solvent (%) 10 10 10 -- (CaCl.sub.2) Draw ratio 1.1 1.2 1.3 1.0*Content of solvent in second solvent content- 13 12 14 8adjusted filamentsSecond wet drawing Step No. 1operation Temp. (°C.) 85 90 90 90 Draw ratio 2.1 2.3 2.0 2.4 Step No. 2 Temp. (° C.) 90 90 90 90 Draw ratio 1.1 1.0* 1.0* 1.0*Dry drawing operationTemperature (°C.) 355 350 355 350Draw ratio 1.72 1.75 1.75 1.75__________________________________________________________________________ Note: *The filaments were washed without drawing.
EXAMPLE 6
A reaction vessel having a capacity of 2 m 3 and equipped with a stirrer, a cooling coil, and a cooling jacket, was charged with a solution of 213.18 kg of isophthalic acid chloride (IPC) having a purity of 99.95% in 750 l of dehydrated tetrahydrofuran (THF) containing 100 ppm of water. The solution was cooled to a temperature of -22° C. while being stirred at a stirring rate of 300 r.p.m.
Separately, a dissolving vessel having a capacity of 1 m 3 and equipped with a stirrer, a cooling coil, and a cooling jacket was charged with a solution of 113.55 kg of m-phenylene diamine (MPDA) having a purity of 99.93% in 750 l of dehydrated THF having a water content of 100 ppm. The solution was cooled to a temperature of -22° C. The cooled MPDA solution in THF was mixed into the cooled IPC solution in THF at an addition rate of 4.3 1/min in a time of 200 minutes in such a manner that the MPDA solution was sprayed through a number of spray nozzles to form fine particles of the solution having a size of 0.1 mm or less, while the IPC solution was stirred. A white milky mixture liquid having a temperature of -15° C. was obtained. After the mixing operation was completed, the mixture liquid was further stirred for about 5 minutes.
A reaction vessel having a capacity of 5 m 3 and equipped with a high speed stirrer was charged with a solution of 156 kg of sodium carbonate in 1750 l of water. While the sodium carbonate solution was stirred at a stirring rate of 1700 rpm, the white milky mixture liquid was rapidly added to the sodium carbonate solution, and the resultant reaction mixture was further stirred for about 5 minutes.
During the above-mentioned stirring operation, the viscosity of the reaction mixture increased a few minutes after the start of the addition operation, and then decreased. A white suspension was obtained, and the resultant suspension was filtered to collect a white powder. The collected white powder was washed with water and then dried. A white poly-m-phenylene isophthalamide powder was obtained in an amount of 249.4 kg, at a yield of 99.8%.
The polymer had an [η] of 2.0.
The molecular weight distribution of the polymer was determined by high speed liquid chromatography, and it was found that the polymer contained 96.9% of a high molecular weight fraction (A), no low molecular weight fraction (B), and 3.1% of oligomer (C). That is, the polymer had a very high content of the high molecular weight fraction (A).
The polymer was dissolved at a concentration of 18% by weight in a solvent consisting of N-methyl-2-pyrrolidone.
The resultant dope solution was subjected to the same wet spinning procedure as those described in Example 2.
The coagulated, undrawn filaments contained 45% by weight of the solvent based on the weight of the polymer in the filaments.
The undrawn filament was first washed with a first washing liquid containing 30% by weight of the solvent dissolved in water at a temperature of 30° C. to carry out a first adjustment of the content of the solvent in the filament to a level of 24%.
The first solvent content-adjusted filaments were first wet drawn in two steps under the following conditions. In the first step, the filaments were wet drawn at a draw ratio of 1.1 in a wet drawing bath consisting of an aqueous solution of 20% by weight of the solvent at a temperature of 45° C. Then, in the second step, the filaments were further wet drawn at a draw ratio of 1.2 in a wet drawing bath consisting of an aqueous solution of 15% by weight of the solvent at a temperature of 50° C.
The first wet drawn filaments were given a second washing with a second washing liquid consisting of water alone at a temperature of 70° C. to carry out a second adjustment of the content of the solvent in the filaments to a level of 14% based on the weight of the polymer in the filaments.
The second washed filaments were second wet drawn in two steps as follows.
In the first step, the filaments were wet drawn at a draw ratio of 2.1 in a wet drawing bath consisting of hot water alone at a temperature of 80° C.
In the second step, the filaments were further wet drawn at a draw ratio of 1.1 in a wet drawing bath consisting of hot water alone at a temperature of 90° C.
The second drawn filaments were dried at a temperature of 130° C., and then were dry drawn at a draw ratio of 1.70 at a temperature of 355° C. by means of a heat drawing plate.
The test results are shown in Table 5.
TABLE 5__________________________________________________________________________ Example No. Comparative ExampleItem Example 2 2 3 4 5 6__________________________________________________________________________Individual filament denier 2 2 2 2 2 2[η] 1.35 1.35 1.30 1.40 1.35 2.0Birefringence (%) 0.16 0.20 0.19 0.20 0.21 0.21Degree of crystallinity (%) 41 51 50 50 52 53Crystalline size (Å) 48 40 41 41 39 37Degree of crystalline orientation 88 93 92 92 93 94Tensile strength (g/d) 5.3 7.8 7.5 7.6 8.1 8.2Ultimate elongation (%) 37 26 28 27 25 25Silk factor 32.2 39.8 39.7 39.5 40.5 41.0Thermal shrinkage at 300° C. 6.0 6.0 5.8 5.6 5.9 5.8__________________________________________________________________________
EXAMPLE 7
A solution of 213.18 kg of isophthalic acid chloride (IPC) having a purity of 99.95% in 750 l of tetrahydrofuran (THF) having a water content of 100 ppm was prepared in a reaction vessel having a capacity of 2 m 3 and equipped with a stirrer, a cooling coil, and a cooling jacket and was cooled to a temperature of -10° C. while the solution was stirred at a stirring rate of 300 r.p.m. Separately, a solution of m-phenylenediamine (MPDA) having a purity of 99.93% in 750 l of THF having a water content of 100 ppm was prepared in a dissolving vessel having a capacity of 1 m 3 and equipped with a stirrer, a cooling coil, and a cooling jacket, and was cooled to a temperature of -15° C. while stirring.
The cooled MPDA/THF solution was added to the cooled IPC/THF solution at a adding rate of 8.5 1/min in a time of 120 minutes, while the cooled MPDA/THF solution was sprayed through a number of nozzles so that the solution aas formed into fine particles having a size of 0.1 mm or less, and while the cooled IPC/THF solution was stirred. A white milky mixture liquid having a temperature of -4° C. was obtained. Ten minutes after the addition operation was completed, 450 l of aniline was added to the milky mixture while the mixture was stirred. Separately, a solution of 195 kg of sodium carbonate in 1750 l of water was charged into a reaction vessel having a capacity of 5 m 3 and equipped with a high speed stirrer, and was stirred at a stirring rate of 1700 r.p.m. The milky mixture was rapidly added to the sodium carbonate solution, 15 minutes after the addition of aniline was completed. The resultant reaction mixture was stirred for about 5 minutes. A few seconds after the start of the addition, the viscosity of the reaction mixture increased and then decreased, and a white suspension was obtained. The white suspension was filtered to collect a white polymer powder, and the collected powder was washed with water and dried. A white polymer powder was obtained in an amount of 249.2 kg at a yield of 99.7%.
The polymer had an [η] of 1.32. In the polymer, the terminals thereof were blocked by aniline in a proportion of 26%, and the polymer contained 4% by weight of oligomer.
The above-mentioned polymerization procedures were repeated ten times. The average value (x) of the intrinsic viscosity of the resultant polymer was 1.32 with a variability (ρ) of 0.03. That is, the polymer had a preferable value of intrinsic viscosity for fiber-forming and the variability of the viscosity was small.
The same procedures as those described in Example 2 were carried out by using the above-mentioned polymer having the aniline-blocked terminals.
The resultant fibers had an individual filament denier of 2, a birefringence of 0.20, a degree of crystallinity of 51%, a crystalline size of 39 Å, a degree of crystalline orientation of 93%, a tensile strength of 7.8 g/denier, an ultimate elongation of 26%, a silk factor of 39.8, and a thermal shrinkage at 300° C. of 5.8%.
After the fibers were dry heated at a temperature of 300° C. for 20 hours, the percentage of the tensile strength of the heated fibers to the original fibers was 94%. | A process is provided for preparing high strength polymetaphenylene isophthalamide fibers by the steps which include extruding a dope solution of a metaphenylene isophthalamide polymer in an organic solvent through a spinneret and into a coagulating liquid form in undrawn polymer filament; adjusting the content of the organic solvent; carrying out a first wet drawing in at least one aqueous wet drawing bath; making a second adjustment of the content of the organic solvent; carrying out a second wet drawing at a specified draw ratio in at least one aqueous wet drawing bath; drying the second wet drawn filament; and dry drawing the dried filament. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to checkpointing the memory state of an executing software application.
BACKGROUND
[0002] Checkpointing is the process by which the memory state of an executing computer program is captured and stored on storage media, such as a disc drive, tape drive or CDROM. The stored state is called an image of the computer program at that instant of time. The image can be reloaded into a computer and the software application restarted to execute from the point where the checkpoint was taken. This is useful as a recovery process where a software application has experienced a fault or crashed. The practice of checkpointing is sometime referred to as taking a back-up, and is a critical feature of most computer systems.
[0003] The practice of checkpointing an entire memory state is somewhat inefficient, however, as it requires a memory storage facility of equal size to the operating computer system and also captures considerable redundant information because most information between across checkpoints does not change. Because of this, incremental checkpoint approaches have been proposed, being either page-based or hash-based.
[0004] In page-based incremental checkpointing techniques, memory protection hardware and support from a native operating system is required in order to track changed memory pages. The software application memory is divided into logical pages, and using support from the operating system, the checkpointing mechanism marks all changed pages as ‘dirty’. At the time of taking a checkpoint, only the pages that have been marked dirty are stored in the checkpoint file. Of course, at the first checkpoint the full memory status is saved because its entirety is required as a baseline. At the time of a re-start, all of the incremental files and the first full checkpoint file are needed to construct a useable checkpoint file.
[0005] Hash-based incremental checkpointing uses a hash-function to compare and identify changed portions (called ‘blocks’) of memory and only saves those in a checkpoint file. Thus the application memory is divided into fixed sized blocks (which may be independent of an operating system page size). A hash-function Ho maps a block B into a unique value H(B), being the H-value of the block. After taking a checkpoint, the hash of each memory block is computed and stored in a Hash table. At the time of taking the next checkpoint, the hash of each of the blocks is re-computed and compared against the previous hashes. If the two hashes differ, then the block is declared changed and it will be stored in the checkpoint file.
[0006] U.S. Pat. No. 6,513,050 (Williams et al), issued on Jan. 28, 2003, teaches an example of hash-based incremental checkpointing based on the use of a cyclic redundancy check. A checkpoint which describes a base file is produced by firstly dividing the base file into a series of segments. For each segment, a segment description is generated which comprises a lossless signature and lossey samples each describing the segment at a different level of resolution. A segments description structure is created from the generated segment descriptions as the checkpoint. The segments description structure is created by selecting a description that adequately distinguishes the segment from the lower level of resolution.
[0007] Both the page-based and hash-based incremental checkpointing techniques still save far more data than may actually be required. This is problematic, particularly as computer systems become larger and more complex since the checkpointing storage memory requirements increase, which is clearly undesirable.
SUMMARY
[0008] The invention is motivated by a first requirement that the determination of changed blocks of memory should not be limited to the granularity of a memory page size or a fixed block size. Rather, the size of the changed blocks should be adaptable to be near-exact to only the changed bytes in memory. Secondly, an algorithm to identify the near-exact boundaries of memory bytes must be efficient and relatively quick in operation. At a minimum, the time taken by the algorithm to identify near-exact changed bytes in changed pages should not exceed the time it would have taken to send the changed pages themselves to an associated I/O sub-system. Additionally, it is desirable to re-create a full checkpoint file from various incremental files.
[0009] The block size is heuristically determined and a table is formed to store hash values of the memory blocks. The stored-values are compared at the next checkpoint time to determine if a block has changed or not. The block boundaries are dynamically adjusted to capture near-exact changed bytes of memory, based on the memory access pattern of the application. Only the blocks marked as ‘changed’ are stored in the checkpoint file. Dynamic adjustment of the block boundaries occurs at each checkpoint time.
[0010] Dynamic adjustment of the block boundaries involves both a split operation and a merge operation. All changed blocks are first sorted in increasing order of size. A split (typically into two) is done for each block starting from the largest size. The split is done based on the observation that not every byte in a blocks changes, rather only a few bytes and these few bytes will most likely lie in one of the two halves. The spilt continues until all blocks are processed or until there is no space in the hash-table. A merge operation acts only on contiguous unchanged blocks. The merge is performed only on two contiguous unchanged blocks at a time, typically being the oldest contiguous unchanged blocks.
DESCRIPTION OF DRAWINGS
[0011] FIG. 1 is a schematic representation of a checkpointing process.
[0012] FIGS. 2A-2D show the adaptation of individual memory block sizes.
[0013] FIG. 3 shows an example of aliasing.
[0014] FIGS. 4A-4F show instances of merging blocks.
[0015] FIG. 5 is a schematic representation of a computer system suitable for performing the techniques described herein.
DETAILED DESCRIPTION
[0000] Overview
[0016] FIG. 1 shows a checkpointing process 10 embodying the invention. One or more software applications 12 are taken to be executing and affecting the memory state of a computer. Assuming the checkpointing processes are starting for the first time, then an initialization process is required. Initial block sizes are determined (step 14 ), which can conveniently be the logical page size of the memory. The memory is then partitioned into equal block sizes (step 16 ). The resulting partition represents an initial checkpoint value submitted to a checkpoint store (step 18 ). A given hash function 20 is applied to each block (step 22 ), to generate a respective hash value for each block, which is stored in a hash value register 24 .
[0017] A checkpoint period of time is allowed to elapse (step 26 ), then the first updating checkpoint process is performed, by applying the hash function 20 to each block (step 28 ), which generates resultant hash values. The new hash values are used to update the previously stored hash values 24 . Before that updating process is performed, the new hash values are compared against the previous hash values. In the event that the respective hash values remain the same then it is concluded that the blocks are unchanged, and an adaptation of block size is performed by a merging of at least two contiguous blocks (step 32 ) (i.e. such that the resultant block is of a size representing the ‘addition’ of the two contiguous blocks). In the event that the comparison of the hash values disagrees, then it is concluded that the block has changed since the last checkpoint instance, and an adaptation of a respective block sizes is performed by a splitting of each block (step 34 ). Only the changed blocks resulting from the splitting step 34 are then passed to the checkpoint store 18 .
[0018] The process 10 then returns to wait for the next checkpoint period to elapse (step 26 ) before continuing as before. In this way an incremental checkpointing is performed that adapts the size of the memory blocks to be near-exact in size to capture only changed bytes of memory. In other words, the block boundaries adapt to capture only changed bytes between checkpointing processes, thus representing the near-minimum information required to be captured, and reducing the incremental checkpoint file size to a near-minimum value.
[0000] Adaptive Incremental Checkpoint Algorithm
[0019] A specific implementation example will now be described. A hash table of size n (in unit of entries) is allocated for an application using a memory of M bytes. (See below for a discussion of how to decide n). This allows the entire application memory to be divided into n blocks, each of initial block size equal to M/n. FIG. 2A shows such an initial memory partitioning. A parameter called age is associated with each block, which defines the number of consecutive times a particular block was not modified. In FIG. 2A , the age of each block is initialized to zero.
[0020] An age tracking mechanism is used to identify blocks which have been unmodified some number of times, and hence could be merged. Merging is based on the assumption that none of these blocks will be changed in the near future (due to the locality of reference principle). As described above, the hash value of each block of the memory is computed and compared against the value stored in the hash table 24 . If the two values differ, then the corresponding block is marked as ‘dirty’ (i.e. has changed) and is saved into the checkpoint file 18 . Otherwise, if the two hash values are same, then the age of the block is incremented, and all un-changed blocks are scanned to find merge opportunities. A merge can happen for all contiguous un-changed blocks having same age. For instance FIG. 2B shows changed (i.e. black) and un-changed (i.e. white) blocks identified in an iteration. All changed blocks will be marked ‘dirty’ (i.e. grayed, as in FIG. 2C ) and all un-changed blocks will be merged in pairs of two (as also shown in FIG. 2C ). At one instance, no more than two contiguous blocks can be merged. This is referred to as a lazy-merge optimization, and is explained further below.
[0021] The algorithm now sorts the list of changed blocks by size, and starts splitting the largest changed block first, until there is no space left in the hash-table 24 , or the list is empty. For each block that is split, age is reset to 0. FIG. 2D shows all changed (grayed) blocks of FIG. 2C as split into two. This split-merge technique continues at each checkpoint instance, and over a period of time. The trend is for each changed block to be of near-minimum possible size, while each un-changed block is of near-maximum possible size.
[0000] Restart Algorithm
[0022] A standalone merge utility is now described, which merges all the incremental checkpoint files into a single non-incremental checkpoint file. The executing application can be restarted from this file. This utility can be used by system administrators to periodically merge various incremental files into a single checkpoint file (online), thereby reducing on space as well as the time to restart the application. The algorithm to merge is as follows:—
Read the latest incremental checkpoint file and write all sections into the final file (since its all sections are latest). For each subsequent file in reverse order, from (n-1) down to 1, find address ranges not already written in the final file, and copy the corresponding blocks into the final file. This ensures that only the most recent blocks are written into the final checkpoint file. The final file thus obtained is the complete nth checkpoint file, ready to be used for re-start.
Determination of Initial Block Size
[0026] The initial block size is generally empirically determined, based on following prior information:
1. Application specific knowledge (based on profiled data) which can specify what is the most typical data page size this application would use. 2. Most commonly used page size on the particular operating system [e.g.: 4 kilobytes in Linux™]. 3. Domain specific knowledge: for instance, scientific programs would operate on large pages, while search programs will operate upon small pages. 4. Any other intuition gained from domain knowledge and expertise, to know the data access pattern of the program(s) that will be executed.
Choice of Hash Function
[0031] As will be readily appreciated by those skilled in the art, there are various known hash functions already available, for example: CRC, X-OR, SHA-1, and SHA-2. The hashing technique, by definition, suffers from a fundamental limitation, being the problem of aliasing. As shown in the FIG. 3 , imagine a block B, which has data as shown in the left hand side, at the time of first checkpoint. A simplistic hash function Xoro is used to calculate a hash value H(B). At the second checkpoint, the data in the block changed as shown in the right hand side of the FIG. 3 . The same hash function Xoro is used to calculate the new hash value H(B′). It would be expected, according the algorithm, that since the block has changed, their hash values must be different, but in fact, they are not. This is the problem of aliasing, where one can incorrectly deduce that a block has not changed, when in reality it has. Therefore, a hash function that suffers from gross aliasing is not suitable.
[0032] Only secure hash functions should be used. By ‘secure’, it is meant that it is computationally very difficult to find two blocks B 1 and B 2 such that H(B 1 )=H(B 2 ). A suitable algorithm is MD5, the algorithm for which is described, for example, in A. J. Menezes, P. C. Oorschot, and S. A. Vanstone, “Handbook of Applied Cryptography”, 1997 , page 347, CRC Press, Inc., and incorporated herein by reference. Of course, other secure hash functions can equally be used.
[0000] Optimal Hash-Table Size
[0033] The ability of the adaptive incremental checkpoint algorithm to adapt to memory access patterns and perform a fine-grained block boundaries adjustment depends on how much space is available in the hash table. If a very small hash table is used, one may not see much benefit because the algorithm would not be able to achieve fine granularity. On the other hand, a large hash table generally consumes additional memory resources which one would like to minimize, and use instead for the application. The size of the hash table would usually depend on how much extra memory is available for scratch use in the system, which in turn depends on the application's memory footprint. This is determined at runtime, and it is sought to utilize anywhere between 5%-10% of application's memory for this purpose.
[0000] Storing the Hash-Table
[0034] The hash table may either be stored in the memory or written to the checkpoint file. Storing the hash table in memory increases the application memory requirement, while storing the hash table in checkpoint file increases its size and adds to the I/O overhead. If the hash table is stored in the checkpoint file, it needs to be read into the memory at the next checkpoint. This further increases the I/O overhead. Moreover, to avoid adding to the application memory overhead, the hash table needs to be read in small blocks and compared against the memory. This not only increases the complexity of implementation but also degrades I/O performance. It is preferred to keep the hash table in the memory. Note that hash table is only used for the checkpointing logic, and it has no role to play at the time of recovery. Hence, even if the hash table was lost, there is no correctness issue with respect to the recovery logic.
[0000] Splitting
[0035] Blocks are split in order to isolate tightest possible boundaries, but care must be taken not to divide into so small chunks that the header overhead (32 bytes) of the hash-table entry becomes greater than the actual data. Moreover, one should split intelligently, to maximize the potential benefits. If large changed blocks are split, there is potential for greater savings. Therefore, the adaptive incremental checkpoint algorithm splits large changed blocks first, and if space remains, splits the smaller blocks. In one embodiment, the split is up to a maximum block size of 32 bytes.
[0000] Merging
[0036] One approach to the merging operation is to be greedy and merge all contiguous un-changed blocks at once, hoping to free-up several hash-table entries. But this approach can backfire if the subject application modifies a large data-structure in alternate iterations. In such a case, at every iteration there is an un-necessary split and merge, and cost is paid in terms of re-hashing time.
[0037] FIG. 4A , shows a few changed (i.e. black) and a few un-changed (i.e. white) blocks at instance I. Assuming there was no lazy-merge, then after the first pass, all changed blocks will be split and all un-changed blocks will be merged as shown in FIG. 4B . Now suppose at instance I+1, memory areas (a,c,fi) change, as shown in FIG. 4C . All changed blocks (i.e. from FIG. 4B ) will again be split, including the block ‘bcde’, which was merged in the previous iteration. In the next iteration I+2, no area from this chunk was modified again, so it is again merged into ‘bcde’, as shown in FIG. 4F . Such a situation easily leads to ‘thrashing’, as splits and merges happen too fast. Therefore, the preference is to do a slow, pairwise merge, using the ageing criterion. This ensures that even if there is a large number of contiguous unchanged blocks, the algorithm merges them in pairs. For n contiguous unchanged blocks of same age, the adaptive incremental checkpointing algorithm will take log(n) checkpoints to merge them into a single block.
[0000] Computer Hardware
[0038] FIG. 5 is a schematic representation of a computer system 100 of a type that is suitable for executing computer software for checkpointing the state of a computer memory. Computer software executes under a suitable operating system installed on the computer system 100 , and may be thought of as comprising various software code means for achieving particular steps.
[0039] The components of the computer system 100 include a computer 120 , a keyboard 110 and mouse 115 , and a video display 190 . The computer 120 includes a processor 140 , a memory 150 , input/output (I/O) interfaces 160 , 165 , a video interface 145 , and a storage device 155 .
[0040] The processor 140 is a central processing unit (CPU) that executes the operating system and the computer software executing under the operating system. The memory 1050 includes random access memory (RAM) and read-only memory (ROM), and is used under direction of the processor 140 .
[0041] The video interface 145 is connected to video display 190 and provides video signals for display on the video display 190 . User input to operate the computer 120 is provided from the keyboard 110 and mouse 115 . The storage device 155 can include a disk drive or any other suitable storage medium.
[0042] Each of the components of the computer 120 is connected to an internal bus 130 that includes data, address, and control buses, to allow components of the computer 120 to communicate with each other via the bus 130 .
[0043] The computer system 100 can be connected to one or more other similar computers via a input/output (I/O) interface 165 using a communication channel 185 to a network, represented as the Internet 180 .
[0044] The computer software may be recorded on a portable storage medium, in which case, the computer software program is accessed by the computer system 100 from the storage device 155 . Alternatively, the computer software can be accessed directly from the Internet 180 by the computer 120 . In either case, a user can interact with the computer system 100 using the keyboard 110 and mouse 115 to operate the programmed computer software executing on the computer 120 .
[0045] Other configurations or types of computer systems can be equally well used to execute computer software that assists in implementing the techniques described herein.
CONCLUSION
[0046] Various alterations and modifications can be made to the techniques and arrangements described herein, as would be apparent to one skilled in the relevant art. | A method, apparatus and computer program product are disclosed for incrementally checkpointing the state of a computer memory in the presence of at least one executing software application at periodic instants. A secure hash function is periodically applied to each partitioned contiguous block of memory to give a periodic block hash value. At each periodic instant, a block hash value for each block is compared with a respective preceding block hash value to determine if said memory block has changed according to whether said block hash values are different. Only changed memory blocks are stored in a checkpoint record. The memory block sizes are adapted at each periodic instant to split changed blocks into at least two parts and to merge only two non-changed contiguous blocks at a time. | 6 |
FIELD OF THE INVENTION
This invention relates to a swimming pool cleaner component and more particularly to the surface engaging disc of certain vacuum operated automatic pool cleaners.
BACKGROUND TO THE INVENTION
Several different models of automatic pool cleaners have been developed which operate on the suction generated by the pool filtration plant. The inlet to the plant is connected through the swimming pool cleaner and a flexible pipe. The cleaner includes a mechanism which intermittently interrupts the flow through the pipe and results in the cleaner being moved stepwise over the surface being cleaned.
This type of cleaner generally requires an annular disc of flexible material around the inlet to the body of the cleaner to assist in holding the cleaner on the surface being cleaned.
The discs generally available are moulded from suitable wear resistant plastics material and are well known. Various minor modifications have been made to these basic annular discs, including variations in the compositions from which they are made, in efforts to improve their effectiveness in operation. Some of these modifications including scalloping of the edge of the disc and a peripheral series of inwardly directed ribs of different configurations to prevent the disc holding up against obstacles in the pool. Also series of holes have been made through the disc to allow water and entrained debris to pass through the disc to the inlet to the cleaner. Ribs and/or channels extending radially from either the central opening through the disc or from the edge of the disc have been provided in an effort to control the flexibility of the discs.
However the flexibility obtained has been mainly across the disc more or less along radial lines.
OBJECT OF THE INVENTION
It is an object of this invention to provide a disc of the kind referred to in which flexibility is imparted in a manner which facilitates the pool cleaner negotiating obstacles protruding from the surface being cleaned.
SUMMARY OF THE INVENTION
In accordance with this invention there is provided a disc for a pool cleaner of the kind referred to in which at least one groove is provided in the undersurface of the disc substantially concentric with the disc periphery.
Further features of the invention provide for there to be a series of radially spaced grooves, for the series to be interconnected by radial grooves symmetrically spaced around the disc and for the radial grooves to extend beyond the inner concentric groove.
The invention also provides for there to be holes through the disc intersecting the inner ends of at least some of the radial grooves and at least some of the intersections of the radial and concentric grooves.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of this invention will become apparent from the following description of one example described below with reference to the accompanying drawings in which
FIG. 1 is the underside of a swimming pool cleaner disc.
DETAILED DESCRIPTION OF THE INVENTION
The disc ( 1 ) illustrated is moulded from suitable plastics material, usually polyurethane.
The disc ( 1 ) is generally of the size of the discs referred to earlier in this specification and may have 400 mm and 105 mm outer and inner diameter respectively.
The outer edge ( 2 ) of the disc ( 1 ) is scalloped as shown and the edge rounded.
The side of the disc which is not shown in the drawing is that which in use is remote from the surface being cleaned. A series of upwardly projecting fins extending a short distance towards the centre of the disc and equally spaced around the periphery will preferably be provided on the disc.
Grooves ( 3 ) which may be made approximately 10 mm wide and 2.5 mm deep, are spaced apart radial from the edge and from each other at a distance of about 30 mm. These grooves ( 3 ) may be of different cross sectional shape provided only they give the flexibility referred to below.
The grooves ( 3 ) provide flexibility which permit the outer part of the disc ( 1 ) which contacts an obstruction in the movement of the pool cleaner in use to fold progressively along the grooves ( 3 ). This further enables the remainder of the disc ( 1 ) to remain in operative contact with the surface being cleaned. Thus the disc ( 1 ) flexes easily while retaining a large surface area in contact with the pool surface.
A symmetrical series of similarly sized grooves ( 4 ) are equidistantly spaced apart and extend radially between the outermost of grooves ( 3 ) into the space ( 5 ) between the central hole ( 6 ) in the disc and the innermost circular grooves ( 3 ).
Holes ( 7 ) are made through the disc ( 1 ) at the inner ends of the radial grooves ( 4 ).
Also holes ( 8 ) are made through the intersection of the radial grooves ( 4 ) and the outermost groove ( 3 ). The holes ( 7 ) can be of larger size than holes ( 8 ) and may be of oblong or other non-circular shape.
The sizes of the grooves and holes through the disc at the ends or intersection of the grooves may be varied to give different characteristics to the effect of the disc in use. Further the preferred material of the disc will be a highly wear resistant polyurethane composition which may also be varied to meet particular requirements.
Convenient sizes for the circular holes illustrated may be 10 mm and the oblong holes may be 10 mm wide and 15 mm deep.
In use the disc has been found to operate satisfactorily over a wide range of flow rates to the filter plant and the grooves and holes provide both added flexibility and facilitate the passage of dirt on the surface being cleaned from that surface through the disc and into the body of the cleaner.
The arrangement of the grooves and holes maintains a substantially even suction over the whole of the undersurface of the disc and this assists materially in retaining the disc against the surface being cleaned. | The invention concerns a surface contacting disc for location around the inlet of a suction operated pool cleaner wherein at least one concentric groove is provided in the surface engaging face of the disc which provides flexibility for the outer part of the disc to fold progressively along the grooves. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to an improved process for preparing (2E)-3-[4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonylamino)pyrimidin-5-yl]-propenal of formula I,
[0000]
[0000] which is an useful intermediate in the preparation of bis[(E)-7-[4-(4-fluorophenyl)-6-isopropyl-2-[methyl(methylsulfonyl)amino]pyrimidin-5-yl]-3R,5S)-3,5-dihydroxyhept-6-enoicacid] calcium salt of Formula II.
[0000]
BACKGROUND OF THE INVENTION
[0002] Rosuvastatin, which is an antihypercholesterolemic drug, is chemically known as (E)-7-[4-(4-fluorophenyl)-6-isopropyl-2-methyl(methylsulfonyl)amino]pyrimidin-5-yl]-(3R,5S)-3,5-dihydroxyhept-6-enoic acid calcium (2:1) salt of formula II. Rosuvastatin was for the first time disclosed in U.S. Pat. No. 5,260,440. Rosuvastatin is being marketed under the proprietary name CRESTOR, as an oral tablet, for the treatment of hypercholesterolemia. In view of the importance of Rosuvastatin as a lipid-lowering agent, several synthetic methods have been reported in the literature to prepare rosuvastatin, some of which are summarized below:
[0003] U.S. Pat. No. 5,260,440 discloses a process for preparing Rosuvastatin in examples. The process is as shown below:
[0000]
[0004] The difficulties in the above process are that the intermediate (A) is not obtained in pure form and its purification is tedious and overall yield is extremely low. Even, when intermediate (A) is not obtained in pure form, further condensation with intermediate (8) to form Rosuvastatin, which does not result in Rosuvastatin of right quality as the product contains unacceptable quantity of impurity levels.
[0005] WO 2000/049014 A1 describes a novel chemical process for the preparation of ter-butyl (E)-(6-{2-[4-(4-fluorophenyl)-6-isopropyl-2-methyl(methylsulfonyl)amino]-pyrimidin-5-yl]vinyl}-(4R,6S)-2,2-dimethyl[1,3]dioxan-4-yl)acetate, which comprises reacting diphenyl-{4-(4-fluorophenyl)-6-isopropyl-2-[methyl(methyl-sulfonyl)amino]pyrimidin-5-ylmethyl}phosphineoxide with tert-butyl 2-[(4R,6S)-6-formyl-2,2-dimethyl-1,3-dioxan-4-yl]acetate and its further conversion to rosuvastatin.
[0006] WO 2003/097614 A2 describes a modified procedure for the preparation of the starting material 4-(4-fluorophenyl)-6-isopropyl-2-[methyl(methylsulfonyl)amino]-pyrimidin-5-carboxaldehyde and further conversion to rosuvastatin by condensing with methyl (3R)-3-[(ter-butyldimethylsilyl)oxy]-5-oxo-6-triphenylphosphoranylidene hexanoate. The condensed product was deprotected using methanesulfonic acid and subsequently converted to Rosuvastatin calcium (2:1) salt.
[0007] WO 2004/014872 A1 describes a process for the manufacture of Rosuvastatin calcium (2:1) salt, which comprises mixing a solution of calcium chloride with a solution of water soluble salt of (E)-7-[4-(4-fluorphenyl)-6-isopropyl-2-[methyl(methylsulfonyl)amino]pyrimidin-5-yl]-(3R,5S)-3,5-dihydroxy-hept-6-enoic acid. This process for the preparation of Rosuvastatin employs the use of phosphorane side chain, the preparation of side chain requires eight synthetic steps and involves expensive reagents. This process is uneconomical and time consuming, hence not appropriate for commercial scale operation.
[0008] WO 2006/100689 A1 discloses a process for preparation of Rosuvastatin, which is as shown below:
[0000]
[0009] In the above scheme, R 1 , R 2 , R 3 represents substituted or unsubstituted phenyl and R 4 represents an aliphatic residue selected from C 1-4 alkyl; R 5 represents C 1-4 alkyl which is optionally substituted by hydroxyl; R 6 represents hydrogen, halogen, C 1-4 alkyl or C 1-4 alkoxy; R 7 represents aliphatic residue and R 8 represents C 1-4 alkyl.
[0010] WO 2006/106526 A1 describes the preparation of Rosuvastatin, which is as shown below:
[0000]
[0011] In the above mentioned scheme, R 1 , R 2 , R 3 are substituted or unsubstituted phenyl and R 4 is an aliphatic residue selected from C 1-4 alkyl; R 5 represents C 1-4 alkyl, M is an alkali metal salt. X represents a halogen; R 6 represents C 1-4 alkyl, which is optionally substituted by hydroxyl; R 7 represents hydrogen, halogen, C 1-4 alkyl or C 1-4 alkoxy; R 8 is an aliphatic residue selected from C 1-4 alkyl.
[0012] WO 2006/076845 A1 describes a process to prepare Rosuvastatin and its salt thereof, which is as shown below:
[0000]
[0013] We have now found an improved process to prepare (2E)-3-[4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonylamino)pyrimidin-5-yl]propenal of Formula I and subsequently converting the compound of Formula I to Rosuvastatin and its pharmaceutically acceptable salts thereof of Formula II.
OBJECTIVE
[0014] The main objective of the present invention is to provide an improved process for preparing (2E)-3-[4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonyl-amino)pyrimidin-5-yl]propenal, which is an useful intermediate in the preparation of Rosuvastatin.
[0015] Yet another objective of the present invention is to provide an improved process for preparing (2E)-3-[4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonyl-amino)pyrimidin-5-yl]propenal, which is simple, industrially applicable and economically viable.
[0016] Another objective of the present invention is to provide a process for a novel intermediate that is used in the preparation of rosuvastatin calcium.
SUMMARY OF THE INVENTION
[0017] The present invention relates to, an improved process for the preparation of (2E)-3-[4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonylamino)pyrimidin-5-yl]-propenal of Formula I,
[0000]
[0000] which comprises:
a) treating 4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonyl-amino)pyrimidin-5-yl]carboxaldehyde of Formula III,
[0000]
with an organometallic reagent to obtain a mixture of substituted ethanol of Formula IV and an olefin of Formula V;
[0000]
b) treating the mixture obtained above with Vilsmeier reagent; and
c) isolating the compound of Formula I.
[0022] In another embodiment of the present invention, the (2E)-3-[4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonylamino)pyrimidin-5-yl]propenal of Formula I, is converted to Rosuvastatin and its pharmaceutically acceptable salts thereof.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The compound of Formula III is treated with organometallic reagent selected from CH 3 MX or CH 3 M or (CH 3 ) n M; M represents magnesium, lithium, zinc, cadmium etc.; X represents chloro, fluoro, iodo, bromo; n represents an integer 1 or 2; in an inert solvent selected from tetrahydrofuran, ether, toluene and mixtures thereof, at a temperature ranging from 0-30° C., preferably 0-10° C., to give a mixture of substituted ethanol of Formula IV and olefin of Formula V. Optionally the mixture is separated. The mixture of Formula IV and Formula V or separated compound is treated with Vilsmeier reagent to give a compound of Formula I.
[0024] In another aspect of the present invention the molar ratio of organometallic reagent based on pyrimidine carboxaldehyde is 1-10, preferably 1-3 moles.
[0025] In yet another aspect of the present invention, the Vilsmeier reagent is prepared from N,N-dimethylformamide and phosphorous oxychloride or N,N-dimethylformamide and oxalyl chloride or N-methylformanilide and phosphorous oxychloride or N-methylformanilide and oxalyl chloride in the presence of a solvent, selected from the group dichloromethane, tetrachloromethane, 1,2-dichlorobenzene, ethylene dichloride, acetonitrile and optionally using an organic base. The organic base is selected from lutidine, tetramethylpyrazine, 2,6-dimethylpyrazine.
[0026] In yet another aspect of the present invention, the Vilsmeier reagent can be prepared and added to the reaction mass or can be prepared in situ during the reaction.
[0027] In yet another aspect of the present invention, molar ratio of Vilsmeier reagent added to the reaction mass is ranging from 1 mole equivalent to 20 mole equivalents, preferably 8-15 mole equivalents based on compound of Formula IV.
[0028] In yet another aspect of the present invention, the compound of Formula IV is dehydrated to olefin compound of Formula V during the course of the reaction, because of which compound of Formula IV and compound of Formula V is formed. The mixture of compound of Formula IV and compound of Formula V were separated using column chromatography.
[0029] In yet another aspect of the present invention, the compound of the Formula I, is further converted to Rosuvastatin and its pharmaceutical acceptable salts thereof, by using the methods known in the art.
[0030] In an embodiment of the present invention, there is provided a novel intermediate, of Formula IV and Formula V
[0000]
[0031] The Formula IV is characterized by 1H NMR (300 MHz, CDCl 3 ): δ (ppm): 1.33 (dd, J=6, 12 Hz; 6H, —CH(CH 3 ) 2 ), 1.58 (d, J=6 Hz, 3H, CH 3 ), 1.76 (d, J=4.5 Hz, 1H, —OH), 3.51 (S, 3H, —NCH 3 ), 3.54 (s, 3H, —SO 2 CH 3 ), 3.82-3.87 (m, 1H, —CH(CH 3 ) 2 ), 5.14-5.17 (m, 1H, —CHOH), 7.12-7.18 (m, 2H, ArH), 7.45-7.5 (m, 2H, ArH)
[0000]
[0032] The Formula V is characterized by 1 H NMR (300 MHz, CDCl 3 ): δ (ppm): 1.29 (d, J=6 Hz, 6H, —CH(CH 3 ) 2 ), 3.44-3.51 (m, 1H, —CH(CH 3 ) 2 ), 3.54 (s, 3H, N—CH 3 ), 3.60 (s, 3H, —SO 2 CH 3 ), 5.20 (dd, J=1.5, 17.7 Hz, 1H, ═CH), 5.5 (dd, J=1.5, 11.4 Hz, 1H, CH═CH 2 ), 7.01-7.12 (m, 2H, ArH), 7.67-7.74 (m, 2H, ArH).
[0033] The invention is illustrated by the following examples, which are provided by way of illustration only and should not be construed to limit the scope of the invention.
Example 1
PREPARATION OF MIXTURE OF 1-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-[(N-METHYL-N-METHYLSULFONYL)AMINO]-PYRIMIDIN-5-YL]-1-HYDROXY ETHANE & 1-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-[(N-METHYL-N-METHYLSULFONYL)AMINO]PYRIMIDIN-5-YL]-ETHENE
[0034] Methyl magnesium chloride solution (3M) (11.87 ml, 0.0356 moles) in tetrahydrofuran was added to a pre-cooled suspension of pyrimidine carboxaldehyde (5 g, 0.0142 moles) in anhydrous tetrahydrofuran (30 ml) under stirring for 30 min at 0-5° C. The reaction mass was stirred at the same temperature. After completion of the reaction, the reaction mass was poured into pre-cooled saturated ammonium chloride solution (100 ml) at 0-5° C. and stirred for 1 h at 5-10° C. The product was extracted into ethyl acetate (150 ml) and washed with saturated aqueous sodium chloride solution. The organic layer was dried over anhydrous sodium sulfate and filtered. The filtrate was distilled under vacuum at 40-45° C. until the traces of ethyl acetate were completely removed to give the title compound.
Yield: 5.3 g
Example 2
PREPARATION OF 1-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-[(N-METHYL-N-METHYLSULFONYL)AMINO]-PYRIMIDIN-5-YL]-1-HYDROXY ETHANE & 1-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-[(N-METHYL-N-METHYLSULFONYL)AMINO]PYRIMIDIN-5-YL]-ETHENE
[0035] Methyl magnesium chloride solution (3M) (11.87 ml, 0.0356 moles) in tetrahydrofuran was added to a pre-cooled suspension of pyrimidine carboxaldehyde (5 g, 0.0142 moles) in anhydrous tetrahydrofuran (30 ml) under stirring for 30 min at 0-5° C. The reaction mass was stirred at the same temperature. After completion of the reaction, the reaction mass was poured into pre-cooled dilute hydrochloric acid (100 ml, 10% v/v) at 5° C. and stirred for 1 h at 5-10° C. Ethyl acetate (100 ml) was added to the reaction mass and stirred for 10 min. The organic layer was separated and aqueous layer is extracted with ethyl acetate (50 ml). The organic extracts were combined and washed with DM water (50 ml) and with 5% saturated aqueous sodium chloride solution (30 ml). The organic layer was dried over anhydrous sodium sulfate and filtered. The filtrate was distilled under vacuum at 40-45° C. until the traces of ethyl acetate were completely removed to give crude 1-[4-(4-fluorophenyl)-6-isopropyl-2-[(n-methyl-n-methylsulfonyl)amino]-pyrimidin-5-yl]-1-hydroxy ethane & 1-[4-(4-fluorophenyl)-6-isopropyl-2-[(n-methyl-n-methylsulfonyl)amino]pyrimidin-5-yl]-ethene.
Yield: 5.2 g
[0036] The above obtained crude 1-[4-(4-fluorophenyl)-6-isopropyl-2-[(n-methyl-n-methylsulfonyl)amino]-pyrimidin-5-yl]-1-hydroxy ethane & 1-[4-(4-fluorophenyl)-6-isopropyl-2-[(n-methyl-n-methylsulfonyl)amino]pyrimidin-5-yl]-ethene was separated by column chromatography to give pure 1-[4-(4-fluorophenyl)-6-isopropyl-2-[(n-methyl-n-methylsulfonyl)amino]-pyrimidin-5-yl]-1-hydroxy ethane & 1-[4-(4-fluorophenyl)-6-isopropyl-2-[(n-methyl-n-methylsulfonyl)amino]pyrimidin-5-yl]-ethene.
[0037] Hydroxy ethane compound—1H NMR (300 MHz, CDCl 3 ): δ (ppm): 1.33 (dd, J=6, 12 Hz; 6H, —CH(CH 3 ) 2 ), 1.58 (d, J=6 Hz, 3H, CH 3 ), 1.76 (d, J=4.5 Hz, 1H, —OH), 3.51 (S, 3H, —NCH 3 ), 3.54 (s, 3H, —SO 2 CH 3 ), 3.82-3.87 (m, 1H, —CH(CH 3 ) 2 ), 5.14-5.17 (m, 1H, —CHOH), 7.12-7.18 (m, 2H, ArH), 7.45-7.5 (m, 2H, ArH)
[0038] Ethene compound— 1 H NMR (300 MHz, CDCl 3 ): δ (ppm): 1.29 (d, J=6 Hz, 6H, —CH(CH 3 ) 2 ), 3.44-3.51 (m, 1H, —CH(CH 3 ) 2 ), 3.54 (s, 3H, N—CH 3 ), 3.60 (s, 3H, —SO 2 CH 3 ), 5.20 (dd, J=1.5, 17.7 Hz, 1H, ═CH), 5.5 (dd, J=1.5, 11.4 Hz, 1H, CH═CH 2 ), 7.01-7.12 (m, 2H, ArH), 7.67-7.74 (m, 2H, ArH)
Example 2
PREPARATION OF (2E)-3-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-(N-METHYL-N-METHYLSULFONYLAMINO)PYRIMIDIN-5-YL]-PROPENAL
[0039] Phosphorous oxychloride (10.03 g, 0.0654 moles) was added to pre-cooled N,N-dimethylformamide (4.85 g, 0.066 moles) under stirring at 5-10° C. and the contents were stirred for 30 min at 40-45° C. To this reagent, a crude mixture of alcohol IV and olefin V (2 g, 0.005 moles, in 5 ml of N,N-dimethylformamide and 1.168 g of lutidine) was added drop wise for 20 min while maintaining the temperature between 25 and 30° C. The reaction mass was stirred for 1 h at the same temperature. Thereafter, the temperature of the reaction mass was slowly raised to 70-75° C. and stirred at the same temperature for 26 h. After completion of the reaction, the reaction mass was cooled to 30° C. and poured into pre-cooled saturated sodium acetate solution (100 ml, 2° C.) and then stirred for 2 h at 20-25° C. To the aqueous solution, ethyl acetate (50 ml) was added and stirred for 10 min at 25-30° C. The resulting organic layer was washed with DM water (2×50 ml) and then concentrated to give the title compound.
Yield: 2 g
[0040] The above crude pyrimidine propenaldehyde (2 g) was chromatographed over silica gel using 5% ethyl acetate and hexanes as eluant to give the pure pyrimidine propenaldehyde.
Yield: 1.0 g
Example 3
PREPARATION OF (2E)-3-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-(N-METHYL-N-METHYLSULFONYLAMINO)PYRIMIDIN-5-YL]PROPENAL
[0041] Phosphorous oxychloride (50.06 g, 0.326 moles) was added to pre-cooled N,N-dimethylformamide (23.86 g, 0.326 moles) under stirring at 5-10° C. The contents were stirred for 30 min at 40-45° C. To the reaction mass, a crude mixture of alcohol IV and olefin V (10 g, 0.0272 moles) in 20 ml of N,N-dimethylformamide was added drop wise in 20 min by maintaining the temperature at 25-30° C. The contents were stirred for 1 h at 25-30° C., then slowly raised the temperature of the reaction mass to 70-75° C. and stirred at the same temperature for 30 h. After completion of the reaction, the reaction mass was poured into pre-cooled DM water (250 ml, 2° C.), stirred for 30 min at 15-20° C. and then adjusted the pH to 7.8 with 25% aqueous sodium hydroxide solution (250 ml) at 15-20° C.
[0042] The resulting suspension was stirred for 30 min at 15-20° C. Ethyl acetate (150 ml) was added and stirred for 10 min at 15-20° C. The aqueous layer was back extracted with ethyl acetate (50 ml). The combined organic extracts were washed with DM water (2×250 ml). The resulting organic layer was then subjected to carbon treatment prior to distillation to obtain crude pyrimidine propenal.
Yield: 9.5 g
[0043] The above crude pyrimidine propenal was dissolved in ethanol (27 ml) and stirred for 20 h at 20-25° C. The resulting mass was cooled to 5° C. and stirred for 1 h at 0-5° C. The precipitated product was collected, washed with chilled ethanol (13 ml, −5° C.) and then dried under vacuum at 45° C. to give pure pyrimidine propenal.
Yield: 4.2 g
Chromatographic Purity (by HPLC): 94.56%
Example 4
PREPARATION OF (2E)-3-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-(N-METHYL-N-METHYLSULFONYLAMINO)PYRIMIDIN-5-YL]PROPENAL
[0044] Phosphorous oxychloride (41.78 g, 0.272 moles) was added to pre-cooled N,N-dimethyl-formamide (19.89 g, 0.272 moles) under stirring at 5-10° C. The contents were stirred for 30 min at 40-45° C. To the reaction mass, a crude mixture of alcohol IV and olefin V (10 g) in 20 ml of N,N-dimethylformamide was added drop wise in 20 min maintaining the temperature at 25-30° C. The contents were stirred for 1 h at 25-30° C., then slowly raised the temperature to 70-75° C. and stirred at the same temperature for 18 h. After completion of the reaction, the reaction mass was poured into pre-cooled DM water (250 ml, 5° C.), stirred for 1 h at 15-20° C. and then adjusted the pH to 7.5 with 25% aqueous sodium hydroxide solution (180 ml) at 15-20° C. The product was extracted with ethyl acetate (150 ml) and washed with DM water (2×100 ml). The resulting organic layer was treated with carbon and filtered the solution through hyflo. The filtrate was concentrated under vacuum to give crude pyrimidine propenaldehyde.
Yield: 9.5 g
[0045] The crude pyrimidine propenaldehyde (9.5 g) was dissolved in ethyl acetate (20 ml) at 20-25° C. and then n-heptane (80 ml) was added. This mass was stirred for 2 h at 25-30° C. The resulting mass was cooled to 5° C. and stirred for 1 h at 0-5° C. After filtration the solid was washed with pre-cooled n-heptane (20 ml, 2° C.) and then dried under vacuum at 35° C. to give the pure pyrimidine propenaldehyde
Yield: 6 g
Example 5
PREPARATION OF (2E)-3-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-(N-METHYL-N-METHYLSULFONYLAMINO)PYRIMIDIN-5-YL]PROPENAL
[0046] Phosphorous oxychloride (8.35 g, 0.0545 moles) was added to N-methylformanilide (17.36 g, 0.0545 moles) under stirring at 5-10° C. The contents were stirred for 30 min at 40-45° C. To the reaction mass, a crude mixture of alcohol IV and olefin V (2 g, 0.0054 moles) was added in 5 min at 25-30° C. The contents were stirred for 1 h at 25-30° C., then slowly raised the temperature of reaction mass to 70-75° C. and stirred at the same temperature for 20 h. After completion of the reaction, the reaction mass was poured into pre-cooled DM water (100 ml, 2° C.), stirred for 1 h at 15-20° C. and then adjusted the pH to 7.5 with 25% aqueous sodium hydroxide solution (40 ml) at 15-20° C. The product was extracted into ethyl acetate (100 ml), charcolized and concentrated to yield 1.8 g of crude pyrimidine propenaldehyde as an oily mass.
[0047] The crude pyrimidine propenaldehyde (1.8 g) was dissolved in ethyl acetate (4 ml) and treated with n-heptane (32 ml). The reaction mass was stirred for 2 h at 25-30° C. The resulting mass was cooled to 5° C. and stirred for 30 min at 0-5° C. Filtered the mass, washed with pre-cooled n-heptane (4 ml, 0° C.) and then dried under vacuum at 35° C. to give the pure pyrimidine propenaldehyde.
Yield: 0.5 g
Example 6
PREPARATION OF (2E)-3-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-(N-METHYL-N-METHYLSULFONYLAMINO)PYRIMIDIN-5-YL]PROPENAL
[0048] Phosphorous oxychloride (12.53 g, 0.081 moles) was added to pre-cooled N,N-dimethylformamide (5.96 g, 0.081 moles) under stirring at 5-10° C. The contents were stirred for 30 min at 40-45° C. To the reaction mass, a crude mixture of alcohol IV and olefin V (3 g) in methylene chloride (9 ml) was added in 10 min while maintaining the temperature at 25-30° C. The contents were stirred for 1 h at 25-30° C., then slowly raised the temperature to 60-65° C. and stirred at the same temperature for 40 h. After completion of the reaction, the reaction mass was poured into pre-cooled DM water (150 ml, 2° C.), stirred for 1 h at 15-20° C. and then the pH was adjusted to 8 with 25% aqueous sodium hydroxide solution (40 ml) at 15-20° C. The product was extracted with methylene chloride (150 ml), washed with DM water (2×100 ml), charcolized and concentrated to give crude pyrimidine propenaldehyde.
Yield: 3.05 g
[0049] The crude pyrimidine propenaldehyde (3 g) was stirred with ethyl acetate (6 ml) at 20-25° C. and then added n-heptane (24 ml). The mixture was stirred for 3 h at 25-30° C. The resulting mass was cooled to 5° C. and stirred for 30 min at 0-5° C. The precipitated mass was filtered, washed with chilled n-heptane (6 ml) and dried to give the pure pyrimidine propenaldehyde.
Yield: 1.6 g
Chromatographic Purity (by HPLC): 96.8%
Example 7
PREPARATION OF (2E)-3-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-(N-METHYL-N-METHYLSULFONYLAMINO)PYRIMIDIN-5-YL]PROPENAL
[0050] Phosphorous oxychloride (20.89 g, 0.136 moles) was added to pre-cooled N,N-dimethylformamide (9.94 g, 0.136 moles) under stirring at 5-10° C. The contents were stirred for 30 min at 40-45° C. To the reaction mass, a crude mixture of alcohol IV and olefin V (5 g) dissolved in 10 ml of N,N-dimethylformamide was added drop wise in 15 min maintaining the temperature at 25-30° C. The contents were stirred for 1 h at 25-30° C., then slowly raised the temperature to 70-75° C. and stirred at the same temperature to complete the reaction (30 h). After completion of the reaction, cooled the reaction mass to 30° C., poured into pre-cooled DM water (250 ml), stirred for 1 h at 15-20° C. and then adjusted the pH to 8 with 25% aqueous sodium hydroxide solution (66 ml) at 15-20° C. Methylene chloride (50 ml) was added and stirred for 10 min at the same temperature. The layers were separated and the aqueous layer was back extracted with methylene chloride (35 ml). The combined organic extracts were washed with DM water (2×50 ml). The resulting organic layer was then subjected to carbon treatment. Filtered the mass through hyflo, washed with methylene chloride (30 ml) and the resulting filtrate was distilled under vacuum until the traces of methylene chloride were completely removed to give crude pyrimidine propenaldehyde.
Yield: 5 g
[0051] The crude pyrimidine propenaldehyde (5 g) was dissolved in ethyl acetate (10 ml) at 20-25° C. and then added n-heptane (40 ml). The mixture was stirred for 2 h at 25-30° C. The resulting mass was cooled to 5° C. and stirred for 30 min at 0-5° C. Filtered the mass, washed with pre-cooled n-heptane (10 ml, 2° C.) and then dried under vacuum at 35° C. to give pure pyrimidine propenaldehyde.
Yield: 3 g
Example 8
PREPARATION OF (2E)-3-[4-(4-FLUOROPHENYL)-6-ISOPROPYL-2-(N-METHYL-N-METHYLSULFONYLAMINO)PYRIMIDIN-5-YL]PROPENAL
[0052] A crude mixture of alcohol IV and olefin V (5 g) was dissolved in N,N-dimethylformamide (20 ml) and treated with phosphorous oxychloride (20.8 g) at 0-5° C. The resulting reaction mass was allowed to stir for 12 h and heated at 80-85° C. for 24 h. After completion of the reaction, the reaction mass was poured on crushed ice and stirred for 1 h and the pH of this reaction mass was adjusted to 8.0-8.5 with aqueous sodium hydroxide. The product was taken in methylene chloride and worked-up as described in the example 7, to give crude pyrimidine propenaldehyde.
Yield: 5 g
[0053] The crude pyrimidine propenaldehyde (5 g) was recrystallized from ethyl acetate and n-heptane (2:8) to give pure pyrimidine propenaldehyde.
[0000] Yield: 3.5 g | The present invention relates to an improved process for preparing (2E)-3-[4-(4-fluorophenyl)-6-isopropyl-2-(N-methyl-N-methylsulfonylamino)pyrimidin-5-yl]-propenal of formula (I), which is an useful intermediate in the preparation of Rosuvastatin. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to novel polyfunctional acyl silane photocrosslinking agents, photocrosslinkable compositions comprising the same and a photocrosslinking process using the same.
2. Description of the Prior Art
We are aware of no prior art which discloses the polyfunctional acyl silanes of the present invention or suggests the use of the same in photocrosslinking compositions.
The closest prior art of which we are aware is represented by U.S. Pat. No. 2,940,853 Sagura et al which discloses bis-azides as photocrosslinking agents for the photocrosslinking of polymers.
U.S. Pat. No. 3,758,306 Roos discloses photopolymerizable compositions and elements containing organosilanes.
U.S. Pat. No. 3,924,520 Boardman et al deals with preparing lithographic plates utilizing vinyl monomers containing hydrolyzable silane groups.
U.S. Pat. No. 3,953,212 Miyano discloses a presensitized lithoprinting plate comprising a support and a coating layer of a mixture of a photosensitive material and a silicone rubber.
U.S. Pat. No. 4,245,056 Bock et al discloses crosslinking high density polyethylenes with t-octyl silicon peroxides.
SUMMARY OF THE INVENTION
The present invention provides novel polyfunctional acyl silanes which are particularly effective as high sensitivity photocrosslinking agents for the photocrosslinking of polymers.
The present invention further provides photocrosslinkable polymer systems and methods of photocrosslinking such polymer systems.
The major object of the present invention is to provide novel photocrosslinking agents, polymer systems comprising the same and processes of photocrosslinking using the same.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The novel polyfunctional acyl silanes of the present invention are bifunctional, trifunctional or tetrafunctional acyl silanes. Bifunctional acyl silanes are preferred.
Accordingly, they have more than one acyl silane moiety per molecule.
They can be represented by the following formula: ##STR2##
In the above formula, A can be --O--R--O or --NH--R--NH--; moiety A links the two substituted phenyl moieties.
In moiety A, R can be --(CH 2 ) n --, where n is 1-12, preferably 1-10 and most preferably 1-6, or ##STR3## where R 2 can be hydrogen, alkyl, halogen, alkoxy or the group ##STR4## where R 3 and R 4 can be C 1 to C 6 alkyl or hydrogen, with the proviso that R 3 and R 4 are not simultaneously hydrogen.
Preferred alkyl groups for R 2 include C 1 to C 6 alkyl groups; preferred halogen atoms for R 2 are chlorine, fluorine, bromine and iodine and preferred alkoxy groups for R 2 include C 1 to C 6 alkoxy groups.
It is most preferred that when group R comprises the phenyl moiety substituted with R 2 that the linkages to the --O-- atoms or the --NH-- groups be para each other, with meta providing intermediate results and ortho providing worse results.
The ##STR5## groups on each phenyl moiety may be the same or different. It is preferred that they be the same. They may be substituted ortho, meta or para the position that the phenyl group is bonded to the A group. It is most preferred that substitution be para, with meta substitution providing intermediate effects and ortho substitution providing worse effects from the viewpoint of steric and electronic effects and sensitivity to irradiation. Para substitution is far superior to meta or ortho substitution.
R 2 can be electron donating or electron withdrawing; the exact nature of R 2 is not overly important.
If the polyfunctional acyl silanes of the present invention are bifunctional, they have the capability to photocrosslink two polymer chains; if trifunctional they have the capability to photocrosslink three polymer chains and if tetrafunctional they have the capability to photocrosslink four polymer chains.
R 1 is an unsubstituted alkyl group or an aryl group. Preferably, R 1 is an alkyl group with 1 to 6 carbon atoms or a phenyl or naphthyl group. Most preferably, R 1 is methyl. Preferred groups include, using the abbreviations Me to represent methyl, t-Bu to represent tertiary butyl and Ph to represent phenyl, Me 3 Si, t-BuMe 2 Si, Ph 3 Si and t-BuPh 2 Si.
The currently most preferred polyfunctional acyl silane is the following bis-acylsilane: ##STR6##
The main reason for preference is the excellent compatibility thereof with the polymer matrix, e.g., a hydroxyethylmethacrylate/n-butyl methacrylate copolymer matrix (HEMA/butyl methacrylate copolymer). Other acylsilanes with longer spacer groups, e.g., (CH 2 ) 6 instead of CH 2 , did not provide films of a quality as good as the above bis-acylsilane.
Homopolymers, copolymers and graft copolymers can be crosslinked using the novel polyfunctional acyl silanes of the present invention. The nature of the polymer photocrosslinked is not overly important so long as the polymer has OH and/or NH 2 groups. Illustrative polymers include polymers formed from vinyl alcohol, hydroxy styrene, acrylic acid, methacrylic acid, hydroxyalkyl acrylates, hydroxyalkyl methacrylates, acrylamides and vinylamines. These materials can, of course, be substituted. For example, a typical substituted monomer would include poly-α-alkyl acrylic acid. Preferably any alkyl group will have from 1 to 6 carbon atoms.
The nature of the comonomer or graft comonomer is not overly important; the comonomer containing the reactive functionality OH and/or NH 2 should, however, comprise at least about 10 mole % of any copolymer or graft copolymer. Mixtures of homopolymers, copolymers and/or graft copolymers can, of course, be used.
Obviously in a homopolymer every recurring unit will have the required OH and/or NH 2 reactive functionality. This will not generally be the case in a copolymer or graft copolymer, though this could be the situation where both comonomers contain the reactive OH and/or NH 2 functionality; in the case of a copolymer or graft copolymer it is preferred that at least one out of every four comonomer units have the OH and/or NH 2 reactive functionality, and it is most preferred that at least one out of every three comonomer units have the reactive functionality OH and/or NH 2 .
Since we generally prefer to achieve the maximum reaction possible (maximum crosslinking), usually the greater the amount of monomer units which contain the OH and/or NH 2 groups, the better. For instance, in the later presented Example where a HEMA/butylmethacrylate copolymer is used, the copolymer comprises 81.4% HEMA/18.6% n-butylmethacrylate monomer units. In fact, based on results to date we have not found any comonomers or graft comonomers that are not useful so long as the final copolymer or graft copolymer comprises at least about 10 mole % of the comonomer containing the reactive functionality OH and/or NH 2 . When a graft copolymer is formed with a backbone which does not contain the reactive functionality OH and/or NH 2 , the comonomer containing the reactive functionality OH and/or NH 2 is grafted onto the parent polymer. Techniques of forming such copolymers or graft copolymers are well known in the art and will not be recited herein. We expect the polyalkenes and polyalkene oxides to be most useful in forming graft copolymers, for example, materials such as polyethylene and polypropylene oxide should provide excellent results. More than two comonomers may, of course, be used in forming a copolymer or a graft copolymer.
For best results, it is preferred that any polymer photocrosslinked using the novel polyfunctional acyl silanes of the present invention have a high molecular weight (molecular weights herein are weight average unless otherwise indicated), most preferably at least about 20,000 up to about 100,000. Polymers of a molecular weight greater than about 100,000 can be used so long as films can be cast therefrom. As molecular weight increases, sensitivity increases, and this is the major reason that we prefer to use higher molecular weight materials.
It is to be noted that we prefer that the reactive functionality OH and/or NH 2 be farther removed from the polymer backbone to which it is attached rather than being directly attached. For example, with HEMA, where the reactive functionality OH is separated from the chain to which it is attached, we achieve greater sensitivity then with polyvinyl alcohol. As can be seen from the listing of earlier illustrated polymers which containing the reactive functionality OH and/or NH 2 , we most prefer to use vinyl polymers with a relatively low number of carbon atoms as the comonomer containing the reactive functionality OH and/or NH 2 .
Useful solvent(s) for film casting and for image development include ethers such as THF, dioxane, lower alcohols such as ethanol, isopropanol, propanol, butanol, etc., ketones such as acetone, methylethyl ketone, methylisobutyl ketone, cyclohexanone, etc., esters such as ethyl acetate, Cellosolve, etc., amides such as dimethyl formamide, dimethyl acetamide, etc., halogenated hydrocarbons such as dichloromethane, chloroform, chlorobenzene, etc.
We usually use a mixture of solvents, typically a mixture of a relatively good solvent for the system in combination with a relatively poor solvent for the system. The criteria that we use in selecting any particular solvent mixture or any particular solvent is to insure that all components are soluble in the solvent(s), the solvent does not evaporate too fast for ease of use, the resulting system shows a viscosity adapted to the procedures selected for applying the system, typically spinning, and the system exhibits good film forming properties.
The polyfunctional acyl silanes of the present invention can be used to photocrosslink polymers containing the reactive OH or NH 2 moiety, or both of such moieties, upon exposure to radiation. Preferably the radiation is ultraviolet radiation, but we believe that electron beams, X-rays and gamma-rays can also be used with equal success.
Crosslinking is best achieved at an intensity of about 10 to about 100 millijoules/cm 2 , though this is not limitative, and we expect that sensitivity significantly lower than 10 mJ/cm 2 are achievable.
The novel photocrosslinkable systems of the present invention can be used in any environment where photocrosslinkable polymers have been used in the past. They find particular application in the manufacture of integrated circuits as a negative photoresist.
In use, the polymer, a convenient solvent and the novel polyfunctional acyl silane photocrosslinking agent(s) of the present invention are mixed, most conveniently with a trace of pyridine to stabilize the final photocrosslinked product. Usually a trace amount up to about 2 wt % of a stabilizer, such as pyridine, based on the weight of solvent is used.
While the use of a sensitizer is optional, it substantially increases sensitivity. To date, Michler's ketone has provided the best results.
The polyfunctional acyl silanes of the present invention show a tendency to crystallize out of films; accordingly, we prefer to use from about 5 to about 25 wt %, more preferably from about 10 to about 15 wt % of the polyfunctional acyl silane or polyfunctional acyl silanes, based on the weight of the total formulation after solvent drive-off (hereafter all percentages are weight percentages based on the weight of the total formulation after solvent drive-off unless otherwise indicated).
When a sensitizer is used, and for practical purposes a sensitizer will generally be used to increase sensitivity, normally it is used in an amount of about 10 wt % to about 20 wt % of the total formulation. If too much sensitizer is used, as will be appreciated by one skilled in the art, film properties are deteriorated. For example, we obtain better results when the amount of sensitizer is reduced to 10 wt % and the amount of polyfunctional acyl silane was increased to 20 wt % as opposed to the situation where the amount of sensitizer used was 20 wt % and the amount of polyfunctional acyl silane was 10 wt %.
The reason that a stabilizer should be present in the final product of the present invention is that the photocrosslinked film produced in accordance with the present invention, due to the presence of the polyfunctional acyl silane, will tend to hydrolyze unless a tertiary amine is present. Based on results to date, aliphatic and aromatic tertiary amines in general are useful. The amount of amine is not overly important so long as a trace amount is present. In addition to pyridine, other commonly available tertiary amines useful to perform a stabilizing function in accordance with the present invention include quinoline and triethylamine. Other tertiary amines may, of course, be used.
Following application of the system, typically by spinning, though any means can be used, the system is then pre-baked at, e.g., 80° C. under vacuum for about 30 minutes to out gas solvent.
The system is merely applied to yield a dry resist layer of a thickness as is conventional in the art and which can vary substantially depending on the use. This will be apparent to one skilled in the art.
The system is then ready for exposure and photocrosslinking, normally using ultraviolet radiation at levels as earlier described.
The exposed photocrosslinked system can then be developed in any convenient solvent, for example, ethanol (1 volume part):acetone (5 volume parts) for 1 to 2 minutes at room temperature.
Normally a post-bake is then conducted to remove residual solvent, for example, at 80° C. for an appropriate time. We have found that 1 hour is more than adequate to dry residual solvent off.
After use, if desired, the photocrosslinked material can then be stripped with pure tetrahydrofuran, pure ethanol, etc.
By choosing an appropriate solvent(s) for film casting and for image development as earlier exemplified, we have increased the sensitivity to 11 mJ/cm 2 . This sensitivity is very high for negative resist formulations that are resistant to oxygen plasma etching. This is the only negative resist we know, (sensitive to mid UV) which contains silicon in the crosslinking agent. Therefore, it is recommended that the amount of polyfunctional acyl silane used should be higher than is the case with conventional bis-azides, so that the resulting imaged layer has enough silicon content to be resistant to oxygen plasma etching if this is desired or necessary. This is not done with bis-azide resists.
Our results to date establish that the polyfunctional acyl silanes of the present invention are:
Useful in applications in general where conventional bis-azide-based resists are used in a manner substantially identical to bis-azide based resists; and
Have built-in resistance to oxygen plasma etching, a capability not illustrated in bis-azide resists; and
A typical synthesis procedure per the present invention is schematically illustrated below and then explained in detail. ##STR7##
Synthesis of 2-(4-hydroxyphenyl)-1,3-dithiane: (1)
4-Hydroxybenzaldehyde (46 g, 0.377 mol), recrystallized from benzene, and 1,3-propanedithiol (45 ml, 0.449 mol) were added to dry chloroform. The reaction mixture was stirred at 0° C. and HCl gas was bubbled through the solution for 10 minutes. After the exothermic reaction stopped the solution was refluxed for 10 hours. A white precipitate formed. This was filtered off and the chloroform solution was washed with water three times, dried (MgSo 4 ) and evaporated under reduced pressure to yield a light yellow solid. White needles were obtained after recrystallization from chloroform, MP=151°-152° C. The white precipitate was also recrystallized from chloroform to yield white needles that melted at 151°-152° C. IR and NMR confirmed the two compounds to be identical. Total yield after recrystallization: 99%.
NMR(CDCl) 7.26(d), 6.86(d), 5.22(s), 2.86(m) and 2.01(m).
IR(KBr) 3300 cm -1 (OH), 910 cm -1 (dithiane ring). The aldehyde peaks at 2700 cm -1 and 2800 cm -1 and the carbonyl peak at 2670 cm -1 disappeared.
Synthesis of bis(2-(4-phenoxy)-1,3-dithiane) methane: (2)
1 (10 g, 47 mmol) was dissolved in NaOH(aq) with tetrabutyl ammonium hydrogen sulfate (2 g). Dibromomethane (4.1 g, 24 mmol), dissolved in benzene, was added and the two phase solutions mechanically stirred at reflux for 8 hours. The reaction system was cooled to room temperature and the layers separated. The benzene layer was washed with water, 10% KOH, water and dried over MgSO 4 . Evaporation under reduced pressure yielded a white solid that was flash chromatographed on silica gel using CHCl 3 as the eluant. MP=171°-172° C., yield (97.4%).
NMR (CDCl 3 ) 7.35(d), 7.09(d), 5.68(s), 5.11(s), 2.91(m) and 2.07(m).
IR(KBr), the peak at 3300 cm -1 disappeared.
General Procedure for the Preparation of 2-Lithio-1,3-dithiane Solutions in THF
A dry three-neck flask fitted with a reflux condenser, two addition funnels and a magnetic stir bar is flushed with dry argon. The addition funnels are sealed with septa and the condenser is fitted with an argon balloon. The dithiane (1 mol) in dry THF is added by syringe into one of the addition funnels. The flask is cooled down to -30° C. and the dithiane solution added to the flask. The funnel is rinsed with THF to insure complete transfer. n-BuLi (1.6M in hexane, 2 mol) is then added dropwise via the other addition funnel. A dark red color appeared after the addition. The solution was stirred at -30° C. for 2 hours.
Silylation of the 2-Lithio-1,3-dithiane Solutions in THF
A typical silylation procedure is as follows:
Freshly distilled chlorosilane (2 mol) is added dropwise at -30° C. The dark red color immediately turns clear after the addition. The reaction solution is allowed to reach room temperature whereupon a white precipitate formed (LiCl) and stirring is continued for 4 hours. The reaction is carefully quenched with water. The bulk of the solvent is removed under reduced pressure and the residue taken up in CH 2 Cl 2 . The CH 2 Cl 2 is washed with water, 10% KOH, water, dried over Na 2 SO 4 and evaporated under reduced pressure to yield a pale yellow solid. Recrystallization from CH 2 Cl 2 yielded a white solid.
NMR (CDCl 3 ) 7.78(d), 7.18(d), 5.76(s), 2.48(m), 1.97(m) and 0.1(s).
IR(KBr) peaks at 1240 cm -1 and 840 cm -1 correspond to the trimethylsilyl group.
General Procedure for the Hydrolysis of 2-Silyl-1,3-dithiane Derivatives
Mercuric Chloride Method
A solution of the silyl dithiane in aqueous 90% methanol is added at 25° C. to a stirring solution of mercuric chloride (4.4 mol) in the same solvent mixture (25 ml). Mercuric oxide (2.2 mol) is added to buffer the reaction mixture. The dithianemercuric chloride complex separated as a flocculent white precipitate. The mixture is stirred and refluxed under argon for 8-10 hours. The mixture is cooled and filtered. The filter cake is washed with chloroform and the organic phase is washed with water, ammonium acetate, water and brine and dried over sodium sulfate. Evaporation of the solvent yielded a yellow gummy solid which upon flash chromatography gave a yellow solid.
Sulfuryl Chloride Method
When the substituent(s) on the silicon were aromatic, this method gave the best results. A solution of sulfuryl chloride (2.4 mol) in dichloromethane is added dropwise at room temperature to a stirring solution of the silyl dithiane (1 mol) and wet silica gel (0.5 g) in dichloromethane. After stirring for 4-5 hours at room temperature, powdered potassium carbonate is added to the reaction mixture and stirring is continued for 30 minutes. Filtration and evaporation under reduced pressure yields a yellow gummy solid which gave a yellow solid after flash chromatography.
Other polyfunctional acyl silanes can be formed in an anologous matter by changing the starting materials in a manner which will be obvious to one skilled in the art.
Having thus generally described the invention, the following Example is presented.
EXAMPLE
Four photocrosslinkable compositions were formed by well mixing the components set forth in the following Table. There was no criticality to the mixing procedure, rather, all components were merely dissolved in the DMF.
The system was then spin coated in a conventional manner onto a transparent substrate to a conventional thickness as is commonly used for electronic circuit manufacture.
Following spin casting, the system was prebaked at 80° C. for 30 minutes under vacuum to remove solvent.
Each of the four systems was then image-wise exposed using mid-UV at 410 nm and an intensity as shown by the Sensitivity Figure given in mJ/cm 2 in the Table.
The resulting crosslinked photoresists were then developed in an ethanol-acetone mixture (1:5 v/v) at room temperature for 1 to 2 minutes. In each instance, the crosslinked photoresist, which was a negative photoresist, was cleanly removed in the unexposed areas yet remained adherent to the substrate in desired areas.
TABLE______________________________________ Composition (pphr)______________________________________Bis (Acylsilane) 26.8 26.8 13.4 13.4Michler's ketone 13.4 26.8 13.4 0HEMA/butylmeth- 100 100 100 100acrylate copolymer(M.W. ca. 30,000)Pyridine 67 67 67 67DMF 15240 15240 15240 15240Sensitivity (mJ/cm.sup.2) 11 27 60 1000______________________________________
It is expected that the use of higher molecular weight polymers and trifunctional (or tetrafunctional) acylsilanes will result in even significantly higher sensitivity.
While there have been described what are at present considered to be the preferred embodiments of this invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the invention, and it is, therefore, intended to cover all such changes and modifications as fall within the true spirit and scope of the invention. | Polyfunctional acyl silanes of the formula ##STR1## are disclosed as novel crosslinking agents. Composition and processes involving the same are also disclosed. | 2 |
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